CORNHUSKERS WIND ESTATE

P.O. Box 17000Kernel Street, Nebraska 84673-9864

CEO: Jerome Wilson

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Table of Contents1. Project Description and Goals............................................................................................ 4

1.1 Project Scope.................................................................................................................................. 41.2 Workflow and Methodology.......................................................................................................4

2. Project Site and Area........................................................................................................... 7

3. Met Tower.............................................................................................................................. 83.1 Location, Instruments and Data................................................................................................8

4. Wind Data............................................................................................................................ 124.1 Process of Quality Control and Analysis...............................................................................134.2 Wind Climate and Wind Data Analysis................................................................................15

5. Wind Flow and Resource Modeling...............................................................................255.1 Flow Model and Input Data..................................................................................................... 26

5.2 Resource Grids..........................................................................................................................................285.3 Resource Grid 1........................................................................................................................................285.4 Resource Grid 2......................................................................................................................................285.5 Resource Grid 3......................................................................................................................................28

5.2 Results and Wind Maps............................................................................................................ 28

6. Site Assessment and GIS Analysis..................................................................................326.1 Setbacks........................................................................................................................................ 326.2 Set Back Matrix.......................................................................................................................... 33

7. Project Wind Turbines...................................................................................................... 357.1 Technology and Specification..................................................................................................38

Siemens SWT 2.3............................................................................................................................................38Clipper 2.5 C96................................................................................................................................................39G.E 2.75-103.....................................................................................................................................................39Suzlon S88 2.1.................................................................................................................................................40Vestas V80-1.8.................................................................................................................................................40Vestas V112-3.0..............................................................................................................................................41

8. Layout Design and Micro Siting...................................................................................... 428.1 Final Layout and Design of Turbines....................................................................................42

9. Site Suitability Analysis.................................................................................................. 43

10. Wind Farm Estimated Productions..............................................................................4610.1 Preliminary estimated AEP calculations.............................................................................46

WTG’s Comparison.......................................................................................................................................4810.2 Modeled AEP Calculations of Final Layout.......................................................................49

11. Project Economics............................................................................................................ 5011.1 Financial model and input data.............................................................................................5111.2 Debt/Equity, Taxes and Abatements....................................................................................53

12. Environmental Analysis and Biological Impacts.......................................................5311.1 Fatal Flaws Analysis................................................................................................................ 5411.2 Noise, Shadow Flickering, Visibility, Safety, Radar, Telecommunication..................6211.3 Biological Impacts.................................................................................................................... 66

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11.3 Water Resource and Soil Erosion.........................................................................................6711.4 Public Health and Safety Considerations............................................................................6911.5 Ground Transportation and Traffic....................................................................................7011.5 Solid and Hazardous Waste................................................................................................... 7111.6 Air Quality and Climate Impacts.........................................................................................7111.7 Socioeconomics and Land Values.........................................................................................7211.8 Archaeological and Cultural Resources..............................................................................73

13. Grid Interconnection....................................................................................................... 7413.1 Capacity, Voltage and ECC analysis....................................................................................7413.2 Loads, System Protection and Conditions..........................................................................76

14. Permitting.......................................................................................................................... 7914.1 Federal, State and Local......................................................................................................... 7914.2 Land Use and Building Permits............................................................................................81

15. Land Agreements, Land Owners Consideration.......................................................8215.1 Terms, Rights and Compensation........................................................................................ 8215.2 Royalty, Indemnification and Reclamation Provisions....................................................8315.3 Public Outreach........................................................................................................................ 84

16. Construction...................................................................................................................... 8416.1 Collection Lines, Service Roads and Logistics...................................................................8516.2 Contracting and Building Site...............................................................................................86

17. Post Construction Monitoring and O&M...................................................................87

18. Project Lifetime, Decommissioning and Remediation..............................................88

19. Conclusion.......................................................................................................................... 89

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1. Project Description and Goals

1.1 Project Scope

Selection of site for the installation of the met tower is a very complex job.

Hence, various factors are involved which will need to be addressed before

finalizing the location. The goal of this project is to design a 50MW or better

wind farm. We want to have the maximum possible energy output and at the

best price while maximizing the use of land and funds. The typical amount

of wake loss should be below 5% for the entire project and no more than 2-

3% for each turbine. This wind farm will be the most cost efficient and

affordable route with the highest possible profits.

1.2 Workflow and Methodology

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The objective of the project is to identify a wind resourceful area in Brown

County, Nebraska where future wind power projects can be installed.

Detailed wind resource assessment is considered essential for estimation of

the wind power potential and evaluation of the most promising site for wind

farm development. In order to achieve this objective, a met tower was

erected at the selected site displayed in Fig.2. The complete measurement of

wind data comprised of four anemometers for measuring wind speed, two

wind vanes for wind direction measurement, one temperature, and humidity

sensors. The wind speed is the most essential site indicator; therefore,

anemometers were installed at three different heights to determine wind

shear individuality.

The project from Windographer is imported directly into WAsP, where data

created were observed, generalized, and predict wind climates. Observed

wind climate refers to the general nature of the cleaned data for the entire

area around the met tower. The generalized wind climate is the specific wind

climate around the met tower at the given heights and locations of

instrumentation. To generate the predicted wind climate, which is the

climate for given turbine locations, the data is further analyzed to account

for the topography of the site, and how the topography may affect the

behavior of the wind around each turbine site. The predicted wind climate is

used to calculate wake effect losses at each site, and ultimately, the annual

energy production for each turbine and the site as a whole. Once the project

has been imported into WAsP from Windographer and the predicted wind

climate has been calculated, we created three resource grids to begin

building the wind farm. The vector map for all of the possible surrounding

areas is presented at 500, 250 and 50 meter resolution, from which we

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selected an area which appeared to have good wind resources and

topography.

Wind Atlas Analysis and Application Program (WAsP) was then used to

assess wind resource assessment, horizontal and vertical extrapolation of

wind data can then be performed through WAsP. It contains a complete set

of models to calculate the effects on the wind on sheltering obstacles,

surface roughness changes, and terrain variations.WAsP also calculates the

ruggedness index (RIX), which uses numerical values to indicate how rough

the terrain is, and as a result, whether or not the flow of the wind will likely

become separated and more turbulent or not. A RIX value of ~0% means

that flow will stay attached, whereas a value greater than 0% means that

flow will likely become separated in some places. While we did not

encounter any obstacles with this project site, there is still on obstacle layer

present in the project in WAsP. Obstacles are defined as anything which

could affect the behavior of the wind, or which we would need to create

siting setbacks.

Furthermore, once the collected data was retrieved and stored on the servers.

Data is then validated manually and through wind data retrieval software to

screen the data for any inconsistency or error and the missing data is

reported. The reason for erroneous data like faulty sensor were immediately

detected and rectified to improve the reliability of the data. Data validation

was done by verification of data records, time sequences, and range test.

Relational checks were made by verifying relationships between different

physical parameters. It is a critical step because accuracy of the WAsP

predictions depends on the accuracy of the met tower location. After the data

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is being validated, the data is being processed for usage. Validated 10 min

data steps were converted into hourly average data base using WAsP.

Average wind speeds and annual wind speed values are then calculated from

the software. Wind rose is developed for the wind direction data received

from the site. Temperature data was also received and monthly averages

were calculated. The complete data set of approximately 23 months was

analyzed to conclude the results of the wind farms feasibility.

2. Project Site and Area Brown County lies in the north central region of Nebraska. It is bordered on

the north by the Niobrara River and Keya Paha County, to the west by

Cherry County, to the south by Blaine and Loup Counties, and to the east by

Rock County. Brown County is twenty-six miles wide and averages forty-

six miles in length containing 1,214 square miles of territory. Brown County

is divided into three physiographic regions. The largest portion of the county

is in the Sand Hills region. It is composed of sandy loam soil and is very

hilly. There are numerous lakes and marshes to be found in the valleys. In

the northeast corner of the county the land is classified into the Holt Table

category, characterized by gently rolling plains. On the county's western

border lies the Niobrara River Valley which is one of Nebraska's most

naturally scenic and beautiful regions.

The chosen site for the wind farm is basically just an agricultural farmland

just north of two major cities, Johnstown and Ainsworth. Within the area

just southeast towards the right bottom corner of the project site there are

multiple crop circles, which indicate that there are a lot of farming activities

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present. On the other hand, North side of the project area has little to no

farming activities present. There is a canyon running through from north to

south of the site location, which is displayed as blue lines running through

the project. The met tower location and the site are also easily accessible by

dirt roads, making this area an ideal location to construct a wind farm

project.

Figure 1- Google Earth Sat Image of Project Area

3. Met Tower

3.1 Location, Instruments and Data

Figure 2 is a Google map image of the monitoring site meteorological tower

location and the surrounding area.

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Figure 2 -Google Map Image of Met Tower Location

Figure 3 is a Google Earth sat image of the meteorological tower of the

monitoring site location, which displays agricultural activities and semi dry

flat land features.

Figure 3-Google Earth Sat Image of Met Tower Location

The data used for the present analysis are from September 14, 2007 to July

30, 2009 for the site. The tubular meteorological tower data used was given

for the met tower located at 42°43'36.55"N and 100° 1'14.58"W. The

selected site for the installation of the met tower is an elevated area

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approximately 2500 ft. Surrounding areas consist of agricultural farmlands,

whereas, the population is mostly on the southeast corner of the project area.

Instrumentation is located at 10, 30 and 60 meters providing wind speed, 30

and 60 meters for wind direction, and 2 meters for temperature of the given

heights. The Met Tower is configured with anemometers (to measure wind

speed), which are capable of recording wind pressure or wind velocity. Since

speed and pressure are so closely related, many anemometers are able to tell

us both values.

This consists of three hemispherical cups attached at right angles to each

other and then placed on the met tower. The moving air would then push the

cups until they were moving in circles. The rotating cups in turn rotate the

inner shaft along a vertical axis of rotation. Then the inner shaft transports

the information to computers, which record the number of times the cups

rotate and then calculates the average wind speed. Correspondingly, wind

vanes measure wind direction. The wind vane is mounted on a central

rotation shaft, which allows the vane to move freely. The surface area of the

vane is unevenly distributed on either side of the shaft. The side with the

larger surface area will be pushed further by the wind and therefore, the

smaller surface area will point in the direction the wind is blowing from.

Additional data, such as pressure and temperature, will be recorded through

an air pressure and temperature sensor mounted on the met tower. Typically,

this is used to determine the overall density of the air in the project area for

the application of the power formula. The wind data is sampled

continuously, recorded approximately over 10-minute intervals by a data

logger, and then transmitted remotely using a modem and internet

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connection. From this data, we can then find minimum, maximum, and

standard deviation values for each height, as well as turbulence intensity,

wind power density, and surface roughness, among other values.

After taking into account the topography factors, the following results are

attained for the annual data, including wind speed and direction collected at

the met tower. The met data included 10 minute average of wind speed and

direction.

ParameterMeasured Emergent

Discrepancy

Mean wind speed [m/s] unknown 8.1 unknownMean power density [W/m²] unknown 496 W/m² unknown

Figure 4-Results from Observed Wind Climate

The complete dataset runs from September 2008 to July 2009. As shown

below, the information provided in Figure 5 gives all location information

for the meteorological tower used for this project, as well as average

environmental conditions, and calculated wind power and wind shear

coefficients. The wind power coefficients are especially important because

they give us the wind power density at 80 meters above ground, which is

essential for calculating power in the wind, and ultimately, project

economics. The data was processed using Windographer software.

Data Set Summary  Variable ValueLatitude N 42°43'36.55"

LongitudeW 100° 1'14.58”

Elevation 789 mStart date 9/14/2007 0:00

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End date 7/30/2009 0:00Duration 23 monthsLength of time step 10 minutesCalm threshold 0 m/sMean temperature 16.8 °CMean pressure 92.14 kPaMean air density 1.109 kg/m³Power density at 50m 362 W/m²

Figure 5-Met Tower Dataset Summary

4. Wind Data

Before WAsP can project and estimate wind speeds, direction and power

production at chosen locations, the provided wind data has to be analyzed.

The 10 minute wind measurements are analyzed and a statistical summary of

the observed, site specific wind climate is calculated. The output is a wind

rose and the wind speed distributions in different sectors. A Weibull

distribution function is then fitted to the measured histogram to provide

scale and shape parameters A and k for each sector (see figure 6). The

Weibull distribution is well established for use with wind statistics as the

natural distribution often fits the Weibull shape .The observed wind data is

converted into a generalized wind climate also shown in Figure 5. The wind

observations have been cleaned with respect to site conditions such as,

buildings, surface roughness etc. This information was acquired from

different sources and was then converted into a map format which is

readable by WAsP.

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Figure 6-Met Data of Wind Data

4.1 Process of Quality Control and Analysis

Figure 7 displays the Flags by Rules code for the data set, to begin the

quality control process a data set was given in excel format with two sheets

from two different time periods. In order to connect both sheets they were

appended in Windographer and then configured the codes. Ex.CH1Avg. the

data set in excel were then decoded by labeling what type of sensor, what

height it’s at and the units it’s using. It was then imported into the program

and it calculated the three main graphs, the vertical wind shear profile, the

monthly mean wind speeds, the wind frequency rose and the diurnal wind

speed profile. After data set sheet one has been calculated, in order to

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combine both data into one program, sheet two was appended from the same

data logger/met tower to avoid having the same properties for the data.

After data has been appended, configured and calculated. The start of the

Quality Control Process was flag by rules, where we were able to flag for

odd data, negative wind speeds or wind speed in the negative direction,

icing, tower shadowing, Standard deviation range, Wind speed max and min

range. The primary purpose of quality control of observational data is

missing data detection, error detection and possible error corrections in order

to ensure the highest possible reasonable standard of accuracy for the

optimum use of the data. The first flag we added to the data was the “invalid

temperature flag” which flags for values of temperature outside possible

range of -40 to 50 degrees Celsius. Anything invalid is also considered to be

one time step. We then checked for “invalid wind speed” that is outside the

range of 0 to 30 for winds below 0 and greater 30 m/s. We could also test for

“invalid wind direction” outside the range of 0 to 360 degrees for invalid

wind outside range of 360 degrees.

Furthermore, we can then check for “icing” and the reason why we chose to

check for icing last is because we want to be able to have good data before

we start searching for environmental errors. These are typically more

complicated code because they require an “and” command and they also

require two to three time steps intervals because one time step is too often.

However, for this project we used the three time step; first icing we checked

for was “icing wind speed” which flags for sensors which are frozen and

then we checked for “icing wind direction” which also flags for sensors

which are frozen. Lastly, there are many other ways to search for data if you

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know something happened by flagging manually by finding the date with

bad data you don’t like and apply it to icing or invalid code; there is also the

flag by scatter plot which allows you to flag for bad data between two

sensors and flag by tower shadowing where the tower is either speeding up

or slowing down the sensor based on the wind direction.

Figure 7-Flag by Rules

4.2 Wind Climate and Wind Data Analysis

Figure 8 gives the wind speeds from each pair of anemometers at 10m, 30m,

and 60m have been consolidated for both the power law and log law

calculations. As shown, both power law and log law approach yield

comparable results at the heights of measured data. This indicates the

amount of wind the turbines capture at certain heights. It is of crucial

importance in wind energy; its knowledge allows designating the energy

efficiency of the turbine. However, for extrapolating upwards 80m to 100m,

the log law yields slightly more conservative values than the power law for

the increased wind speed at higher elevations. Because the data shows the

shear declining going from 10m to 60m AGL, the more conservative log law

is the more appropriate for extrapolating upwards from 60m AGL.

The wind shear has a complex effect on the aerodynamics as the wind speed

experience by each blade. Refraction by wind shear is of paramount

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importance in determining propagation paths of wind turbine noise. Wind

shear refraction shapes propagation paths in all directions, strongly affecting

intensity of sound at nearby homes and communities. Vertical wind shear is

a principal cause of noise levels generated from the turbines. Also it may

contribute to periodic fluctuations in electrical power output of the wind

turbine generator. Not only is that but, for the wind farm project the vertical

wind shear is an important design parameter because and it strongly

influence the lifetime of major components, such as blades and gearbox.

Figure 8-Vertical Wind Shear Profile

Figure 9 shows the wind speeds at each anemometer height, which are 60m,

30m and 10m as they plotted against time to depict the seasonal trends.

Wind speeds typically increase with increased height above the ground. The

collected data follows the pattern. The fall through March-April are the

windiest, and through August-September are the least windy.

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Figure 9- Monthly Wind Speed Profile

Figures 10 show the mean diurnal profile of the wind data which is related to

the cost of energy. The monthly profiles are important because they

incorporate average values for each month in all years given. This can give

the developers and utilities an idea of what months they can expect more or

less wind power in, aiding in future forecasting. As shown in the diagram,

based on this location wind speeds at 1200hrs (12:00 noon) to 1800hrs (6:00

p.m) slows down drastically. Also, from about 7:00 a.m to 9:00 a.m wind

speeds increased for the remainder of the day. This basically means that

there is a lower capacity for this site.

Diurnal wind speed profiles are important for the same reason developers

and utilities need to know what time of day the wind power is greatest or

least to help with forecasting. It is essential that enough power is supplied to

the grid at all times; so accurate wind forecasting is essential. So to

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recapitulate, diurnal profiles elaborate on the lower wind speeds increase

during the day while the upper wind speeds decrease respectively.

Figure 10-Diurnal Wind Speed Profile

Figure 11 is a wind direction frequency rose, illustrating the dominant wind

direction(s) for the given tower data which is observed from the southeast.

This is the most important during project development, as it will drastically

affect the layout of the wind turbines at the wind farm. Wind turbines are

placed perpendicular to the prevailing wind direction to minimize wake

effect losses and turbulent load on the wind turbines. This can have a

significant effect on project economics due to reduced energy production or

the need to replace fatigued turbines.

This rose is also important during project operation, as turbines will need to

be yawed toward the prevailing wind direction, should it ever deviate from

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the average direction. For the wind farm project, predictable impacts of the

tower can be seen when the wind must go around the tower “in the tower

shadow” to reach one of the anemometers. The sensor in the shadow of the

tower sees turbulent wind often at reduced wind speeds, though the absolute

difference in wind speeds may be small, the ratio can be an identifiable

marker for the impact of the tower. This can be seen graphically in figure 8

above. The wind speed data from the anemometer not in the tower shadow is

used when the wind is coming from directions that will cause tower shading

Figure 11- Wind Frequency Rose

.The total energy wind rose shown in Figure 12 which portrays slightly

similar characteristics to the wind direction frequency does make a huge

difference in total energy consumed by the wind turbines. It’s exclusively

for plotting the proportion of wind energy coming from each direction

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sector. Windographer uses the wind power density calculated for each wind

speed sensor for each time step, sorts them by direction sector and calculates

the total energy available for each direction over the entire period of the data

set, or the portion you have chosen in your filter settings.

The total energy wind rose is used in wind projects to portray the amount of

energy that will come into the wind project from various directions. The

wind rose helps developers site the turbines in such a way as to minimize

wake losses from other turbines developed at the site. The graph displays the

portion of the total wind energy coming from each direction sector. This

information is ultimately important when predicting the project economics,

therefore helping investors to properly analyze the layout of the wind farm

for project optimization output.

Figure 12-Total Energy Wind Rose

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The probability distribution function displayed in Figure 13is typically

described using a Weibull distribution. There are two commonly used

factors to describe the characteristics of this distribution function, the

Weibull k and Weibull c factors. The Weibull k value is a unit less measure

indicating how widely the wind speeds are distributed about the mean with

values. The Weibull c is the scale factor for the distribution related to the

annual mean wind speed.

The best fit Weibull distribution parameters for the measured data at 60 m

are k = 2.50m/s and c = 8.99 m/s displayed in the figure. The distribution

shown in identifies that the most frequent winds are between 7 m/s and 10

m/s, as measured by the speed sensor at 60m.

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Figure 13-Probability Distribution Function

Figure 13 illustrates the frequency percentage of time that the wind at 60m is

at a given wind speed, which shows how the wind speed distribution varies

throughout the year. To make the graphs more legible to read, representative

distributions are shown only for selected months. As can be seen, the months

July, August, and September are slightly shifted to the left indicating lower

average wind speeds in those months. Likewise, the more windy winter

months show similar shifts to the right. Windographer also calculates the

Weibull distribution curve along the histogram created for the frequency

distribution. It uses the maximum likelihood algorithm, which is also

illustrated in the figure 14 below.

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Figure 13- Monthly Wind Speed Distributions at 60m

Weibull Weibull2 Mean Proportion Power RK c Above Density Squared

Algorithm (m/s) (m/s) 7.902 m/s (W/m2)Maximum likelihood 2.49 8.898 7.894 0.475 476.6 0.99228

Least squares 2.483 8.916 7.91 0.477 480.5 0.99188WAsP 1/2/1900 12:00 8.907 7.903 0.476 476.9 0.99255

Actual data(89,188 time

steps) 7.902 0.476 476.9Figure 14

The wind speed sensor summary shown in figure 15 below is created in the

table’s tab of Windographer. It is a culmination of the entire sensor

information, as well as information that can be calculated from the known

values at sensor height. We have all of the important information for a

sensor at 80 meters, or hub height. This is still synthesized data, and was

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calculated using the log law for 60-meter sensor data. Noted, “MoMM”

stands for mean of monthly means.

VariableSynthesized 80 m

60m WS A

60M WS B

CH3Avg

CH4Avg

CH5Avg

CH6Avg

Measurement height (m) 80 60 60 30 30 10 10Mean wind speed (m/s) 8.431 7.997 7.905 6.739 6.654 5.367 5.327MoMM wind speed (m/s) 8.245 7.869 7.755 6.63 6.553 5.301 5.276Median wind speed (m/s) 8.344 7.9 7.8 6.5 6.4 4.9 4.8Min wind speed (m/s) 0.4 0.4 0.4 0.4 0.4 0.4 0.4Max wind speed (m/s) 24.862 19.9 25.5 23.4 23.7 20.9 21.3Weibull k 2.422 2.51 2.445 2.273 2.286 1.9 1.915Weibull c (m/s) 9.486 8.993 8.892 7.589 7.497 6.045 6.003Mean power density (W/m²) 532 443 436 286 275 173 169MoMM power density (W/m²) 506 426 418 276 266 168 165Mean energy content (kWh/m²/yr) 4,661 3,880 3,819 2,507 2,407 1,515 1,476MoMM energy content (kWh/m²/yr) 4,433 3,736 3,659 2,415 2,328 1,472 1,443Energy pattern factor 1.594 1.558 1.588 1.694 1.691 2.033 2.023Frequency of calms (%) 0 0 0 0 0 0 0Possible data points 98,640 98,640 98,640 98,640 98,640 98,640 98,640Valid data points 89,983 79,897 89,715 91,490 92,925 88,073 86,973Missing data points 8,657 18,743 8,925 7,150 5,715 10,567 11,667Data recovery rate (%) 91.22 81 90.95 92.75 94.21 89.29 88.17

Figure 15-Wind Speed Sensor Summary

Figure 16, 17, and 18 shows the annual statistics for certain values, which

can be found by selecting a certain data column (sensor values) in the table’s

tab of Windographer. Figure16 gives the annual statistics for the 80 meter

synthesized wind speed data, Figure 17 shows the annual statistics for the 60

meter wind direction sensor, and Figure 18 shows the annual statistics for

the 30 meter wind direction sensor. These tables give us a good idea of how

much of the data is good data, as well as how much is bad.

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# YearPossib

le ValidRecove

ryMea

nMedia

n MinMax

Std. Dev.

Weibull k

Weibull c

Data Points

Data Point

sRate (%)

(m/s) (m/s)

(m/s)

(m/s) (m/s) (m/s)

1 2007 15,69615,61

0 99.457.95

3 8.196 0.5 20.4 3.202 2.673 8.923

2 2008 52,70452,64

9 99.9 8.39 8.313 0.5 25.5 3.619 2.469 9.447

3 2009 30,24029,96

1 99.088.61

4 8.546 0.52 26.2 3.602 2.556 9.689All

Data 98,64098,22

0 99.578.38

9 8.359 0.5 26.2 3.557 2.515 9.438MOM

8.244

Figure 16 – Annual Statistics 80m Synthesized Wind Speed

Year Possible Valid Recovery Mean Valid Recovery Median Min MaxStd. Dev.

Data Points

Data Points Rate (%) (°)

Data Points Rate (%) (°) (°) (°) (°)

1 2007 15,696 14,503 92.4 231.6 14,542 92.65 210 1 359 85.92 2008 52,704 49,946 94.77 216 50,010 94.89 198 1 359 86.53 2009 30,240 20,325 67.21 246.3 28,564 94.46 199 1 359 87.7

All Data 98,640 84,774 85.94 224.6 93,116 94.4 200 1 359 86.8

Figure 17 – Annual Statistics 60m Wind Direction

Year Possible Valid Recovery Mean Valid Recovery Median Min MaxStd. Dev.

Data Points

Data Points Rate (%) (°)

Data Points Rate (%) (°) (°) (°) (°)

1 2007 15,696 14,710 93.72 218 14,799 94.29 199 1 358 86.32 2008 52,704 50,407 95.64 188.6 50,706 96.21 178 1 359 88.23 2009 30,240 28,742 95.05 246.2 28,928 95.66 216 1 359 89.3

All Data 98,640 93,859 95.15 210.1 94,433 95.73 190 1 359 88.7

Figure 18 – Annual Statistics 30m Wind Direction

5. Wind Flow and Resource Modeling

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In order to create wind energy models of the proposed area, I used

Windographer and Wasp to determine the coordinates of met tower location,

wind data generated from the project site, and maps were imported for

further analysis. WAsP uses these sets of data to generate the overall wind

statics of the project site. Along with the power curve, WAsP is able to

create outputs. A summary of the procedure is shown in figure 19.

Figure 19- Flow Model Procedure

5.1 Flow Model and Input Data

We used the WAsP flow model to create wind resource modeling for the

area in which will be feasible for project development. Following the

process described earlier in the Workflow and Methodology section, three

resource grids were created, one at 500 meter resolution, and a zoomed-in

resource grid at 250 meter resolution and 50 meter resolution to aid in the

proper placement of wind turbines. In figure 20 below is an image from

resource grid 1of the mean wind speed flow over the project area display

five row of turbines spaced approximately 12 diameters apart.

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MetData Excel Windographer WAsp

Furthermore, the thin brown snake-like lines you see running throughout the

map are called contour lines. The contour lines allow you to infer general

terrain characteristics from their patterns. Whereas, the lines close to

together means that there are steep sections and lines spaced widely apart

indicate more gentle slopes. Hence, in order to get major output from the

wind turbines it’s best to place them in areas with lines that are close

together displaying higher elevation. On the left side and bottom of the map

you notice some numbers running along the outside of the map. These

numbers represent two grid systems that can be used to find your exact

location, they are the latitude and longitude given at equally spaced intervals

between corners. Also, in the bottom right color of the image you can

identify the color scale which shows the least amount of wind resource and

to greatest amount of the project area. (A more detailed explanation of color

scale is mentioned in 5.2 results and wind maps).

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Figure 20-Wind Speed Vector Map of Project Area

5.2 Resource Grids

Figures 21, 22, and 23 contain the Grid Setup Table from the Resource Grid

Report for resource grid 1, 2 and 3. Here we are given the basic information

about the resource grid, including how many columns and rows it contains,

and at what height it was evaluated.

5.3 Resource Grid 1Structure: 44 columns and 44 rows at 500 resolutions give 1936 calculation sites.Boundary: (408415, 4715884) to (430415, 4737884)Nodes: (408665, 4716134) to (430165, 4737634)Height a.g.l.: 80m

Figure 21- Resource Grid 1 Setup

5.4 Resource Grid 2Structure: 49 columns and 42 rows at 250 resolutions give 2058 calculation sites.

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Boundary: (410410, 4725606) to (422660, 4736106)Nodes: (410535, 4725731) to (422535, 4735981)Height a.g.l.: 80m

Figure 22 - Resource Grid 2 Setup

5.5 Resource Grid 3Structure: 145 columns and 136 rows at 50 resolutions give 19720 calculation sites.Boundary: (411341, 4728220) to (418591, 4735020)Nodes: (411366, 4728245) to (418566, 4734995)Height a.g.l.: 80m

Figure 23-Resource Grid 3 Setup

5.2 Results and Wind Maps

Figure 24 is a spatial view of resource grid 1 mean wind speed vector map,

which displays the best possible wind resource in the area for the placement

of the wind turbines. The warm colors like brown, orange, red etc. indicates

higher wind speeds. Cool colors like purple, dark blue, light blue etc.

indicates lower wind speeds, while also accounting for spacing guidelines,

wake effect, etc. The color overlay on the map allows you to compare

different areas of the project site using the color scale located in the bottom

right corner of the map (seen figure 27), which shows highest wind speeds at

9.43 m/s and lowest wind speeds at 7.14 m/s.

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Figure 24-Mean Wind Speed Vector Map

The power density data mapping in figure 25 from the resource grid 1

purpose is to determine the cost efficiency in the distribution of wind power.

The colors on a power density map can be categorized as the blue to light

blue areas is considered as poor density, areas from light blue to green is

considered to fair, areas with yellow to orange is considered to be good and

areas orange to red is considered to have excellent density. The color scale

shown at the bottom (seen figure 28) gives a general idea of which area is

poor, fair, good or excellent for wind power distribution.

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Figure 25-Power Density Vector Map

Figure 26 displays the RIX (Ruggedness Index) data of the resource grid 1

vector map. One objective measure of the steepness or ruggedness of the

terrain around a site is the so called ruggedness index or RIX, defined as the

percentage fraction of the terrain steeper than some critical slope. If the RIX

value is greater than 0%, parts of the terrain are steeper than 0.3 and flow

separation may occur in some sectors. This situation is generally outside the

performance envelope of WAsP and prediction errors may be expected.

Large RIX values will lead to large errors in the flow modeling

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Figure 26-RIX Vector Map

Figure 27 contains the result tables from the Resource Grid 1 report of the

project area. It shows the mean speed values in meters per second, the power

density in watts per meter squared, and the ruggedness index values (as a

percentage) for the resource grid area selected. RIX values greater than 0%

mean that the terrain may be rough enough to result in flow separation of the

wind. This can mean a more turbulent load on our wind turbines, resulting in

shorter useful lifetimes or higher maintenance costs. Resource grid 1 has a

maximum RIX value of 11.5%, which unfortunately, is very high.

Mean Speed [m/s]Maximum Value: 9.43 m/s at (421665, 4737134)Minimum Value: 7.23 m/s at (420165, 4726134)Mean Value: 8.23 m/s

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Power Density [W/m²]Maximum Value: 813 W/m² at (421665, 4737134)Minimum Value: 369 W/m² at (420165, 4726134)Mean Value: 538 W/m²

RIX [%]Maximum Value: 11.5% at (425665, 4728134)Minimum Value: 0.0% at (430165, 4725634)Mean Value: 1.50%

Figure 27-Resource Grid I Results

6. Site Assessment and GIS Analysis

6.1 Setbacks

Setbacks are established to minimize risk of damage or injury from

component failure on property and personnel. The setbacks are usually a

multiple of the total turbine height, from tower base to upper extreme point

of the rotor, as seen in Figure 28 below is a general illustration of how to

measure the rotor diameter, the difference between the hub height and the

turbine’s total (maximum) tip height.

Figure 28-Turbine Dimensions

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Generally the setbacks can vary from 3-5 times the overall turbine height.

Larger setbacks are sometimes required for special areas. In contrast to these

standards, Brown County with more rural development, use building

setbacks and doesn’t necessarily have to distinguish the wind turbines

separately. However, for this project setbacks weren’t of much concern due

to the layouts of the turbines. The wind farm is out of range from any water

bodies, transmission lines, airport, cultural areas, towns, oil/wells, forest,

roads, homes and buildings as shown in figure 29. This image displays

buffer distances of 500m created in Google Earth, which are surrounding

homes that may seem to be in project range.

Figure 29-Buffer Zone of Project Layout

6.2 Set Back Matrix

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Figure 30 contains the setback considered during the wind farm

development based on my turbine layout. Given that most of setbacks were

not a concern for this particular wind project, the primary focus is listed in

the table below. The set back matrix basically illustrates certain buffers

created within and out of the zone. Hence, as far as home/buildings it was

assumed that the setback matrix of 500m and 300m respectively were a safe

distance to determine go zone or no zone.

This is significantly important for the wind farm project because as a

developer it’s required to keep land owner rights in consideration. A wind

turbine within less than 500m of a home or building brings about many

issues whereas the visibility, noise and shadow flicker may be of great

concern for the project development. Building large wind turbines in close

proximity to the public has a negative impact on health such as disturbed

sleep due to noise, racing pulse, heart palpitations, headaches, feeling of

nausea etc. which may be due to the wind turbines noise, shadow flicker or

pressure.

Setback Matrix DistanceHome/Buildings 500m/300m

Figure 30-Set Back Matrix Table

7. Project Wind Turbines

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For this wind project, the turbines that we will be choosing from include the

Vestas V80-1.8, Vestas V112 3.0, Suzlon S88 2.1, Siemens SWT 2.3,

Clipper 2.5 and G.E 2.75, all at 80 meter hub heights. Each turbine is rated

between 1-3 megawatts of nameplate capacity. Figure 31 displays a graph of

the power curves for each turbine using the data that was imported into

Windographer. From this graph, we can gather important information about

each turbine relative to the site that it would be placed at. For instance, we

can see that the Vestas V80-1.8 MW has the highest cut-in speed, as well as

the lowest cut out speed, meaning that it could possibly be a less economical

choice for this site. Hence, the wind turbine that would be more economical

for my project is the Vestas V112 3.0 MW.

Figure 31-Wind Turbine Power Curves

The cut-in speed which is recorded on the power curve indicates the speed at

which the turbines first starts to rotate and generate power. Then the rated

power, which is when the power output reaches the limit that the electrical

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generator is capable of and the rated speed measured signifying the wind

speed at which it is reached. Hence, typically from there is the maximum

level and there is no further rise in output power. Lastly, the cut-out speed

recorderd is a braking system employed to to bring the rotor to a standstill.

Due to the forces on the turbine structure continue to rise and at some point

there is a risk of damage to the rotor. A more detailed illustration on the

power curve is shown below in figure 32.

Figure 32-Typical Wind Turbine Power Curve

The power curves also incorporate calculations for loss factors, listed in

Table 33 below. Each value will be changed according the conditions for a

given site. The overall loss factor for this site is 16.005%. Loss factor

calculations can significantly affect wind turbine efficiency and, ultimately,

model selection.

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Figure 33-Turbines Loss Factor

In figure 34 the wind speed is predicted at hub height for each turbine site

and the power production can then be estimated. The predictions for all

turbines will be presented and separate results for the Clipper 2.5 C96, G.E

2.75, Siemens SWT 2.3, Suzlon S88 2.1, Vestas V80-1.8 and Vestas V112-

3.0 turbine sites. A conservative energy production loss factor of 16% was

assumed in the calculation. The details of the loss factor can be found in

figure 33 mentioned earlier in the report.

Based upon the calculations in figure 35 below, it seems that the G.E 2.75 is

the best choice of turbine for this site with a Net Capacity Factor (NCF) of

44.58 percent. The net capacity factor of a wind turbine is the ratio of its

actual output over a period of time, to its potential output if it were possible

for it to operate at full nameplate capacity indefinitely. Figure 35 displays

the wind turbine output summary for each of the six selected turbines. Here

we can see the net capacity factor for each turbine, how much of the data

was good quality, annual power production estimates, etc. Data in this table

is very useful in determining which turbine would be the best choice for a

given site.

Valid Hub Height

Percentage Of Time

Simple Mean

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At

TimeWind Speed Zero Rated

Net Power Net AEP NCF

Turbine Steps (m/s) Power Power (kW) (kWh/yr) (%)Clipper 2.5 C96 (80m) 89,983 8.43 12.91 7.48 964.6 8,450,058 38.58

Siemens SWT 2.3 (80m) 89,983 8.43 7.24 6.43 1,024.30 8,972,990 44.54Souzlon S88 2.1 (80m) 89,983 8.43 7.31 5.74 809.8 7,094,204 38.56Vestas V112 3.0 (80m) 89,983 8.43 7.24 20.97 1,297.80 11,368,622 43.26Vestas V80-1.8 (80m) 89,983 8.43 12.91 3.51 679.8 5,955,221 37.77

GE 2.75-103 (80m) 89,983 8.43 3.5 9.6 1,226.00 10,739,874 44.58Figure 35-Wind Turbine Summary Table

7.1 Technology and Specification

Siemens SWT 2.3

General data Manufacturer: Siemens (Germany) Model: SWT-2.3-101 Nominal power: 2,300 kW Rotor diameter: 101 m Available model Wind class: IEC IIb Swept area: 8,012 m² Power density: 3.49 m²/kW Number of blades: 3 Power control: Pitch

Rotor Minimum rotor speed: 6 rd/min Maximum rotor speed: 16 rd/min Start-up wind speed: 3 m/s Nominal wind speed: 12 m/s Maximum wind speed: 20 m/s

Gear box Gear box: yes Speed number: 3 Ratio: 1:91

Generator

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Type: ASYNC Number: 1 Output voltage: 750 V

Tower Minimum hub height: 80 m Maximum hub height: 100 m

Clipper 2.5 C96

General data Manufacturer: Clipper (USA) Model: Liberty C96 Nominal power: 2,500 kW Rotor diameter: 96 m Wind class: IEC IIb Swept area: 7,239 m² Power density: 2.9 m²/kW Number of blades: 3 Power control: Pitch

Rotor Minimum rotor speed: 9,6 rd/min Maximum rotor speed: 15,5 rd/min Start-up wind speed: 3,5 m/s Nominal wind speed: 15 m/s Maximum wind speed: 25 m/s

Generator Type: SYNC PM Number: 4 Maximum generator output speed: 15,5 rounds/minute Output voltage: 690 V

Tower Hub height: 80 m

G.E 2.75-103

General data Manufacturer: GE Energy (USA) Model: 2.75-103 Nominal power: 2,750 kW Rotor diameter: 103 m No more available Wind class: TCIII Swept area: 8,333 m² Power density: 3.03 m²/kW Number of blades: 3

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Rotor Start-up wind speed: 3 m/s Nominal wind speed: 13,5 m/s Maximum wind speed: 25 m/s

Generator Type: ASYNC DF Number: 1

Tower Minimum hub height: 75 m Maximum hub height: 123,5 m

Suzlon S88 2.1

General data Manufacturer: Suzlon (India) Model: S88-2.1 Nominal power: 2,100 kW Rotor diameter: 88 m Available model Wind class: IEC IIa Swept area: 6,083 m² Power density: 2.9 m²/kW Number of blades: 3 Power control: Pitch

Rotor Maximum rotor speed: 17,8 rd/min Start-up wind speed: 3,5 m/s Nominal wind speed: 14 m/s Maximum wind speed: 25 m/s

Gear box Gear box: yes Speed number: 3 Ratio: 1:98,8 - 1:118,1

Generator Type: ASYNC Number: 1 Maximum generator output speed: 1830 rounds/minute Output voltage: 600 - 690 V

Tower Hub height: 79 m

Vestas V80-1.8

General data Manufacturer: Vestas (Denmark)

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Model: V80/1800 Nominal power: 1,800 kW Rotor diameter: 80 m Wind class: IEC IIa Offshore model: no Swept area: 5,027 m² Power density: 2.8 m²/kW Number of blades: 3 Power control: Pitch

Rotor Maximum rotor speed: 17 rd/min Start-up wind speed: 3,5 m/s Nominal wind speed: 15 m/s Maximum wind speed: 30 m/s Manufacturer: Vestas

Generator Type: IND Number: 1 Output voltage: 690 V

Tower Minimum hub height: 60 m Maximum hub height: 78 m

Vestas V112-3.0

General data Manufacturer: Vestas (Denmark) Model: V112/3.0 MW Nominal power: 3,000 kW Rotor diameter: 112 m Wind class: IEC II/III Swept area: 9,852 m² Power density: 3.29 m²/kW Number of blades: 3 Power control: Pitch

Rotor Minimum rotor speed: 6,2 rd/min Maximum rotor speed: 17,7 rd/min Start-up wind speed: 3,5 m/s Nominal wind speed: 15,5 m/s Maximum wind speed: 25 m/s

Gear box Gear box: yes Speed number: 4 Ratio: 1:113,0

Generator Type: SYNC PM

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Tower Minimum hub height: 84 m Maximum hub height: 119 m

8. Layout Design and Micro Siting

8.1 Final Layout and Design of Turbines

Figure 36 below displays the final layout of the project with the G.E 2.75

MW wind turbines. There are 28 turbines placed in the most wind

resourceful areas in order to capture the maximum amount of wind coming

from the predominant direction in which the turbines are faced. Each turbine

was spaced approximately 10-15 RD apart from each other to reduce wake

loss.

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Figure 36 - Final Layout

9. Site Suitability Analysis

Figure 36 shows the turbulence intensity for the 60 meter wind speed data.

Turbulence Analysis window allows you to observe how the turbulence in

the wind varies with wind speed, wind direction, month, or hour of day. One

important component of turbulence analysis is the turbulence intensity. The

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turbulence intensity, or TI, is a dimensionless number defined as the

standard deviation of the wind speed within a time step divided by the mean

wind speed over that time step. It is a measure of the gustiness of the wind.

High turbulence can lead to increased turbine wear and potentially increased

operations and maintenance (O&M) costs. Lower wind TI is often higher

when calculated as can be seen in figure 38. At low wind speeds, the

turbulence is of little consequence to the wind turbine itself. Turbulence at

higher wind speeds is often of greater interest and concern to wind turbine

manufacturers.

Figure 37-Turbulence Intensity at Wind Speeds

Figure 38 shows the IEC turbulence ratings relative to the representative TI.

A point of primary interest is the mean TI at 15 m/s, which 0.1% shown in

the Turbulence Intensity summary table below. This indicates relatively high

turbulence that may preclude the use of low wind speed turbines that would

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maximize energy production at this site. The potential wind loading due to

extreme winds must be addressed during the turbine selection process.

Figure 38-Turbulence Intensity at 60m

The turbulence analysis summary table, shown in figure 39 repeats three

numbers that appear in the 15 m/s bin in the table of turbulence versus wind

speed: the number of records in that bin, the mean turbulence intensity in the

bin, and either the characteristic turbulence intensity or the representative

turbulence intensity in the bin, depending on which edition of the

International Electro technical Commission (IEC) standard you have

selected. The table also reports the IEC turbulence category that results from

these 15 m/s statistics. If you view the Turbulence vs. Wind Speed table,

Windographer will highlight the 15 m/s value that corresponds to the key

value in the summary table.

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During project development of the wind turbine, the question arises about

the selected turbine class on-site in that the wind turbine will be operating

and the wind class depends on the site’s turbulence intensity (TI). According

to IEC3 Turbulence category the wind turbine for this project is a class C

displayed in the table above and defines that a representative turbulence

intensity standard is being used. Depending on the wind class, the wind

turbine may be more or less solid and stable in order to withstand loads, to

which the turbines will be exposed to on site. The importance of turbulence

is important to design and choice of an appropriate wind turbine for the site

distinctiveness. Being that the wind turbine class for this project is the

highest at class C, the stronger the turbines structure must be designed in

order to withstand the impulsive and long term fatigue loads and extreme

wind measures.

10. Wind Farm Estimated Productions

10.1 Preliminary estimated AEP calculations

The Cornhuskers wind estate accommodated approximately 5 utility-scale

turbines to produce electricity. For economic purposes, the G.E 2.75 on an

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Figure 39-TI Summary Table

Quantity ValueData points in 15 m/s bin 805

Mean TI at 15 m/s 0.1Representative TI at 15 m/s 0.13

IEC3 turbulence category C

80m tower was selected. This turbine features GE’s 50.2 meter proprietary

blade design that offers a 9 percent AEP increase over the 2.5-100. Focusing

on performance, reliability, acoustic emissions, efficiency, and multi-

generational product evolution. GE’s 2.75-103 wind turbine creates more

value.

In figure 40 below is a layout of the wind farm displaying the each turbines

wake losses with the indication of tan colored, cone shaped image with

calculates the wake loss percentage as seen below. The red lines highlighted

at the tips illustrate the total amount of wake losses of the wind behind the

turbine. In its wake, the turbine is less effective at generating energy for a

certain distance in the downwind direction due to turbulence created by the

upwind turbine. Hence, when sitting a wind farm, it is important to space

turbines as to minimize the impact each has on the others’ power production

capacity and the results shown in figure 41 ais a summary table comparing

all wind turbines. The measured AEP and wake loss percentage from the

wind farm is summarized including the total, average AEP, maximum and

minimum per turbine.

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Figure 40-Mean Wind Speed Vector Map of Wind Farm Layout

WTG’s Comparison

Valid Hub Height Percentage Of Time AtSimple Mean

TimeWind Speed Zero Rated Net Power Net AEP NCF Wake

Turbine Steps (m/s) Power Power (kW) (kWh/yr) (%) Loss %Clipper 2.5 C96 (80m) 89,983 8.43 12.91 7.48 964.6 8,450,058 38.58 2.8

Siemens SWT 2.3 (80m) 89,983 8.43 7.24 6.43 1,024.30 8,972,990 44.54 2.32Souzlon S88 2.1 (80m) 89,983 8.43 7.31 5.74 809.8 7,094,204 38.56 1.97Vestas V112 3.0 (80m) 89,983 8.43 7.24 20.97 1,297.80 11,368,622 43.26 2.47Vestas V80-1.8 (80m) 89,983 8.43 12.91 3.51 679.8 5,955,221 37.77 1.58

GE 2.75-103 (80m) 89,983 8.43 3.5 9.6 1,226.00 10,739,874 44.58 2.15Figure 41-Wind Turbines Summary Table

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10.2 Modeled AEP Calculations of Final Layout

Wind statistics at the turbine hub are converted in power using the power

curve of selected turbine models obtaining the gross Annual Energy

Production (AEP). Declared power curve from the turbine manufacturer are

individually corrected based on the average air density at every turbine site.

Information on air density is derived from measurements or mesoscale data

for the site. Single turbine array losses by direction are determined using

analytical wake models. This approach includes the wake effects in the wind

field as a post-processing step. Other technical losses like turbine

availability, electrical losses, icing etc. are assessed based on traceable

experience and industry standards in order to obtain the net AEP. Figure 41

below provides the statistics for the wind farm, the total, mean, minimum

and maximum gross and net annual energy production (AEP), as well as the

total wake loss calculated in WAsP. In addition, the mean wind speed, mean

power density and ruggedness index RIX. The predicted power production

of the wind farm is 331 GWh. The wake effects are very small here because

the wind farm consists of one row of turbines at right angles to the

prevailing wind direction.

Parameter Total Average MinimumMaximu

mNet AEP [GWh] 330.583 11.807 11.48 12.141

Gross AEP [GWh] 337.862 12.067 11.67 12.452

Wake loss [%] 2.15 - - -Figure 41 - Modeled AEP Calculation

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11. Project Economics

The economics of a wind project depend on the cost of financing, when the

turbine purchase agreement was executed, construction contracts, the type of

machine, the location of the project, and other factors. Cost components for

wind projects include wind resource assessment and site analysis expenses;

the price and parts of the turbine and tower; construction expenses;

permitting and interconnection studies; utility system upgrades,

transformers, protection, and metering equipment; insurance; operations,

warranty, maintenance, and repair; legal and consultation fees. Other factors

that will impact your project economics include your financing costs, the

size of your project, and taxes.

If you own or are a part owner of a commercial scale wind project, the

power purchase agreement (PPA) will be an integral part of your revenue

generation. The PPA is a contract between the owner of a wind farm and a

utility that sets the price of all the power that is sold. Securing a PPA is a

crucial step in the planning stages of a wind project, as it obligates the

agreeing entity to buy your electricity at a certain price for a certain number

of years; this allows you to estimate how much revenue your project will

generate. Various state and federal tax incentives are available for wind

projects. However, to take advantage of these benefits, you will need to

thoroughly understand the eligibility requirements and structure your project

accordingly. The Federal Production Tax Credit (PTC) is an important

incentive, but it can be difficult for private individuals to use to its full

advantage because they lack the ongoing tax liabilities needed for the

incentive. Careful consideration of your personal financial situation and

51

consultations with a tax advisor are recommended for anyone who is

considering investing in a wind project.

11.1 Financial model and input data

Figure 42 below illustrates the development and operating cost site

assessment for the project. The project will need to perform archeological,

environmental impact, and other studies before permits to build are issued.

Your local or state permitting agency may also require other studies and

fees. Common permits are building, conditional and special use, FAA, and

access road. Your local or state zoning authority will be able to help you

determine what permits your project will need to obtain. Legal costs in

permitting can get expensive for projects in areas where possible litigation

might occur from parties affected by the project and often a building permit

fee is based on total project cost. Interconnection studies for the project were

made and depending on the size of the project and where the propose

interconnection is located. Three phase lines are required for large

generators, but you can’t assume that any three phase line can carry the

power from the turbines. You may incur significant unanticipated costs if the

power line near the site does not have the capacity to handle more

electricity. Transmission lines are very expensive to build and difficult to

site.

The interconnection study will outline what impact your project will have on

the power system. The results of this study may require that your project pay

for significant system upgrades to mitigate these issues. Working with an

expert through the interconnection process to make sure that the utility is not

52

adding unnecessary additional costs to the proposed upgrades is making it

difficult to develop the project. If a smaller project can interconnect onto a

distribution line, then it can benefit from a lower cost interconnection

without the necessary substation elements needed for connecting to power

lines. Distribution lines are the lines that bring the energy to the customer,

whereas transmission lines are for transmitting electricity from point to point

using higher voltages to minimize line losses. Also, an installation costs are

all the expenses required to construct and get the turbine up and running

once it arrives. Connecting the turbine to the grid is often done through a

team effort involving the contractor, representatives from the turbine

manufacturer, and engineers from the utility company that owns the power

lines.

Once the project is up in the air and spinning there are periodic and annual

expenses that will need to be accounted for. Some of these expenses will

happen every year such as preventative maintenance of the machines. Other

expenses may happen less frequently or sporadically such as replacement of

parts that have worn out. The best way to understand what is appropriate for

the project is to understand the risks associated with owning a wind project

and ways to mitigate those risks by talking to people who own and operate

projects using the same equipment within your region and learning from

their experience.

Development CostInterconnect Study $ 847,000.00

System Impact Study $ 15,000.00 Environmental Study $ 150,000.00

Permitting $ 200,000.00 Transmission Right-of-ways $ 234,800.00

53

Installed Cost per MW $ 1,751,928.25 Turbine $ 3,960,000.00

Total Project $ 134,898,475.07 O & M $ 419,263.03

Insurance Cost $ 2,016,000.00 Depreciation (1-10) years $ 13,489,847.51

Figure 42 - Development and Operating Cost

11.2 Debt/Equity, Taxes and Abatements

In many cases, developing a community wind project necessitates requesting

a loan from a bank. Loan terms for the debt vary, but typically are 10-15

years for conventional bank loans and up to 20 years for bond financings.

The equity investment in a project is the amount of capital that is not

borrowed, but is invested directly into the project upfront. This may come

from private savings or direct investment by members of a cooperative,

partnership, or LLC that is interested in obtaining a desired rate of return

from the project’s ongoing revenues. In order to be financially competitive,

most wind projects need to take advantage of federal and, where available,

state tax incentives. It is critical to understand the role and mechanics of tax

incentives while developing a commercial-scale community wind project

because these incentives can represent one-half to two thirds of the total

revenue stream over the first 10 years of operation due to the Federal

Production Tax Credit (PTC) and Modified Accelerated Cost-Recovery

System (MACRS) or other type of depreciation that can be applied to wind

energy assets.

12. Environmental Analysis and Biological Impacts

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11.1 Fatal Flaws Analysis

A fatal flaw analysis aims to minimize the investment in feasibility studies

to quickly determine if a site is worth investing significant development time

and capital. Utility scale wind turbines have many siting considerations, and

many of these potential fatal flaws can be identified relatively quickly. The

site must be able to have access for turbine components both new and

existing, and an electrical interconnection or access to one suitable for the

scale of the project. The site must have favorable local ordinances as well as

national impact considerations. Figure 43 below represents a Plat Map of my

proposed site location, which is sited in Brown’s County, Nebraska. There

were approximately 250 landowners in Brown, County. Plat Maps are listed

alphabetically; it gives the legal descriptions of pieces of real property by

lot, street, and block number. However, being that in the figure below there

aren’t no lot, street, nor block number apparent, it shows the land as

subdivided into lots displaying the location and boundaries of individual

parcels with the streets, alleys, easements, and rights of use over the land of

another. Additional information included on the county plat maps are

township names, section numbers, range numbers, lakes and rivers which are

also not apparent on the map provided.

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Figure 43-County Plat Map

Figure 44 represents the Long Range Radar screening of my geometric

single point location of my project. In order to do so I had to obtain the

latitude and longitude of my project location center point. Input the

coordinates so I can determine the project location sustainability. Whereas,

for my location it’s determined “green” which means there are no

anticipated impact to air defense and homeland security radars. However, if

it was “yellow” impact would me more likely moderate and if it was “red”

the overall impact will be high.

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Figure 44-Long Range Radar

Figure 45 illustrates the NEXRAD screening of my geometric single point

project location, which I also obtained by finding the latitude and longitude

of the area. After inputting the results, it calculated the potential impacts to

weather radars and the severity of these impacts are described in colors,

which are green, dark green, yellow and orange. Given these points, as you

can see by diagram my project location is proposed to be “green” known as

“NO Impact Zone” which means that impact is unlikely. Hence, NOAA

would not perform any detailed analysis, but would still like to know about

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the project. As for “dark green” knows “Notification Zone” impacts would

be more possible to occur, “yellow” as the “Consultation Zone” where

impacts are more significant and NOAA would request consultation to

discuss the details of the project and impact analysis, and “orange” the

“Mitigation Zone” also the possibility of significant impacts, requiring

NOAA to request mitigation if a detailed analysis shows that the project will

cause significant impacts.

Figure 45 - NEXRAD Radar

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Figure 46 explains military operations screening, which shows the

preliminary review of any likely impacts to military airspace. However, by

examining the details in this diagram you can determine the results of the

screening. This shows that there are no likely impacts to military airspace.

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Figure 46-Miliatry Operations Radar

Figure 47 below displays the “Long Range Radar” screening type and

Geometric type “Polygon” of the project area for all corners. This diagram

was generated by acquire the latitude and longitude of all four corners the

project area. After submitting all the coordinates the proposed diagram was

produced. Not only that but, as you see its “green” which means that there

no anticipated impact to air defense and homeland security radars. However,

if the project area was determined to be either “yellow” or “red” the impact

to air defense and homeland security radars would be moderate to high,

which will require aeronautical study.

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Figure 47-Long Range Radar

Similar like the “The Long Range Radar” screening type the “NEXPAD”

screening type was generated by acquire the latitude and longitude of all

four corners the project area. After submitting all the coordinates the

proposed diagram was produced. Not only that but, as you see its “green,

referred as the “No Impact Zone” which means that impacts are unlikely and

NOAA will not execute a detailed analysis although they will still want to

know about the project. The severity of impacts is determined in variety of

colors, these are “Dark Green” or “Notification Zone” where there are

possibilities of impacts and it’s optional to consult with NOAA, “Yellow” or

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“Consultation Zone” shows the possibility of significant impacts and NOAA

would request consultation to discuss the project details and do a detailed

impact analysis. Also NOAA would request mitigation of significant

impacts. “Orange” also referred as the “Mitigation Zone” indicates

significant impacts as well and if a detailed analysis shows that the project

will cause significant impacts a mitigation request will be likely. Lastly, the

“No-Build Zone” which would be “red” displays severe impacts and a

detailed analysis will be required. Also, NOAA would request developers to

refrain from building wind turbines 3 km within the NEXRAD

Figure 48-NEXRAD Radar

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11.2 Noise, Shadow Flickering, Visibility, Safety, Radar,

Telecommunication

The assessment of suitability of a certain location for the installation of a

wind farm requires the consideration of multiple impact issues; here we’ll

focus on the visual aspects, safety, radar, telecommunication, shadow flicker

from wind turbines and noise pollution. Wind Turbines generate a broad

spectrum of noise including low frequency noise and infrasound which may

be audible or inaudible. It is widely affirmed that exposure to audible low

frequency noise can cause adverse health effects in humans. Most of the

counties with zoning regulations for wind energy have noise standards

established. The most common standard for commercial wind turbines is 50

dBA. Figure 49 is an image of the noise assessment from a wind turbine on

the wind farm; each circle is 1, 3, and 5 RD’s away from the base of the

tower. Between turbines and dwellings the setbacks are often based on

sound levels that are generally acceptable approximately 1000 to 1320 feet.

The noise is propagated outward by distance and this can be calculated with

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the equation, . For example,

but first in order to find the radius (r), we

have to calculate the diagonal using the equation ,

which then 130 becomes the radius. Moreover, Brown County currently has

neither zoning plan nor setbacks for wind turbines from natural resources,

property lines etc. but the most common setback used for commercial scale

wind turbines in Nebraska is 600 feet from public conservation lands and

wetlands.

Figure 49-Noise Rings

In addition to noise pollution wind turbines also have visual burdens.

Shadow flickering is the phenomenon caused by the moving shadow of the

wind turbine blades moving over a point. The area where flicker is

experienced moves as the sun’s position relative to the ground changes

throughout the day and season to season. As with other shadows, the shaded

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area is larger but moves quickly in the early and late hours of the day and

smaller but more slowly moving in the middle of the day. It should be noted

that shadow flicker does not induce epileptic seizures as the number of

cycles per second produced by commercial wind turbines; generally less

than one per second is well below the strobe effect that causes seizures 5 to

20 per second. Other concerns are raised that are turbine related, shadow

flickering has the potential to cause nausea, dizziness, and disorientation.

Shadow Flickering occurs in a butterfly-like pattern around each turbine. A

more detailed illustration of the shadow flickering butterfly shaped pattern is

shown in figure 50 below.

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Figure 50-Shadow Flicker Butterfly

The butterfly-like shape is made up by lines of shadow flicker impact,

similar to the lines on a topographic map.  For example, a house with

windows facing the proposed turbine located along the blue line could

expect about 30 hours of shadow flicker in a typical year. Furthermore, the

typical special safety requirements for wind turbine development in

Nebraska are; clearance of rotor blades or airfoil must maintain a minimum

of 12 feet of clearance between their lowest point and the ground. All

commercial/Utility WECS (wind electronic conversion system) should have

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a sign or signs posted on tower, transformer and substation, warning of high

voltage. Other signs should be posted on the turbine with emergency contact

information. Also, all turbines whether a commercial/utility WECS, should

be installed with a tubular type tower and consideration should be given to

painted aviation warnings on all towers less than 200 feet. Lastly, all wind

turbines and towers should be white, grey or another non-obstructive color.

11.3 Biological Impacts

Wind energy development impacts wildlife populations in two ways: direct

impacts, such as individuals colliding with infrastructure; and indirect

impacts, such as loss and degradation of habitat. Direct impacts occur when

birds and bats collide with or when bats come in close proximity to moving

turbine blades, towers, or transmission lines servicing wind farms. Although

numerous variables including location of turbines, time of year, weather, and

scavenger removal rates make it difficult to determine trends from multiple

wind farms, some patterns have emerged. Recent studies show direct

impacts may increase significantly when turbines are placed in or near major

migration corridors or natural features used during daily animal travel, for

example, mountain passes, large river valleys, and saddles or the edge of

ridge tops and bluffs, or at migration stopover sites or frequently visited

areas such as wetlands and lakes. Because birds and bats tend to follow or

congregate along these natural landscape features, wind turbines placed near

these features have potential for causing an increase in bird and or bat

mortalities. Bats are likely to experience higher direct mortality rates than

birds at many wind farms, Resident bats in Nebraska are usually associated

with trees or wooded areas and wetlands, where the insects on which they

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feed are abundant. However, bats commonly feed over grasslands and

agricultural fields as well. Recent studies have shown tree roosting

migratory bats are at a higher risk of direct impacts from wind turbines;

three particularly susceptible species are the eastern red bat (Lasiurus

borealis), hoary bat (Lasiurus cinereus), or silver-haired bat (Lasionycteris

noctivagans). Currently there is no clear reason why so many bats are being

killed by turbines and until such reasons are known, extra vigilance should

be used when siting turbines near areas of potential bat stopover and

roosting habitat.

Indirect impacts, such as habitat loss or degradation from wind turbines and

their associated infrastructure, can affect all species in the impacted area,

including plants and non flying animals that are not subject to turbine

collision mortality. These impacts represent an environmental cost that may

be greater than direct impacts. Development of infrastructure can impact

species through loss of habitat due to construction of roads, tower sites,

turbine pads, and other infrastructure within the wind farm. Habitat loss can

result from the physical removal of suitable habitat from the area or through

species’ responses to the change in the habitat which can result in species

being displaced from otherwise suitable habitat near a turbine or other wind

farm infrastructure. These avoidance behaviors could result in a large area of

intact grassland becoming fragmented into smaller use areas, each fragment

being too small to sustain a population of that species over the long term.

11.3 Water Resource and Soil Erosion

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Wind energy requires no use of water resources for operation. Foundations

are not usually any deeper than a standard basement foundation and do not

interfere with water tables. No particulate or heavy metals are released into

the atmosphere which can contaminate water supplies. The final footprint of

a wind turbine is relatively small, approximately 15 feet in diameter, with

some surrounding area needed for maintenance vehicles. Access roads do

take up some land area and in environmentally sensitive areas can fragment

habitat. Soil erosion is another potential environmental problem that

can stem from construction projects. Erosion impacts can include

increased siltation of streambeds, alteration of stream courses, and

increased flooding, leaving scars on the land. Wind developers can

reduce the risk of serious erosion by minimizing the amount of earth

disturbed during construction, principally by eliminating unnecessary

roads, avoiding construction on steep slopes, allowing buffers of

undisturbed soil near drainages and at the edge of plateaus, assuring re-

vegetation of disturbed soils, and designing erosion-control structures

adequate to the task.

The single most reliable technique for limiting erosion is to avoid grading

roads in the first place. During construction there is significant area

disturbed for road construction, burying of transmission lines, construction

of the foundation, and crane pad site. Erosion is a primary concern and must

be addressed through the building permit process, as with other construction

projects. Top soil should be sequestered during construction and replaced

after construction is complete. During operation, agricultural use can be

continued in the area surrounding the turbines. Most state or local agencies

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will require that before building and other permits are issued that you attain

an Industrial National Pollutant Discharge Elimination (NPDES) permit. The

permit assures local and state agencies that you have a plan in place to

minimize erosion from the site and potential harmful effects on water quality

in local lakes and streams from run off or oil and other chemicals that might

be spilled during the construction process.

11.4 Public Health and Safety Considerations

The Brown County Health Department, in collaboration with community

partners, accomplishes its mission by providing services relating to:

communicable disease surveillance and control, prevention of chronic

disease and disability, maternal/child health promotion, management of

environmental hazards, licensing and inspection visits, laboratory services,

and preparation for emergency events in the community. Communicable

disease surveillance and control involves investigation of cases and contacts,

provision of needed health care services and education.  Management of

environmental problems is focused on anima and rabies investigation,

human health hazard evaluation and follow-up, code enforcement, and well

water testing, evaluation and follow up.

Furthermore, for safety consideration the Brown County Emergency

Operations Plan establishes the standardized policies, plans, guidelines and

procedures that will allow all emergency resources, governmental and non-

governmental, to collectively manage and coordinate the preparation,

prevention, response, recovery and mitigation functions effectively and in a

consistent manner, as a team when disaster strikes. In content and in format,

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the Local Emergency Operations Plan (LEOP) is consistent with the

National Incident Management System (NIMS) and with the current

nationwide concept embodied in the Integrated Emergency Management

System (IEMS). This Plan provides for performing specific functions across

the full spectrum of hazards. Most responsibilities, tasks and capabilities

apply across a broad range of hazards. By treating them in this manner

shows an integrated approach to disaster management. Unique aspects of

certain hazards are addressed separately, where necessary. Therefore, this is

truly a multi hazard functional plan.

11.5 Ground Transportation and Traffic

Ground transportation and traffic impacts associated with wind energy

projects typically include impacts on the transportation system itself, the

physical properties of the road system and impacts on traffic that uses the

transportation system. Such impacts arise almost entirely during the

construction period. Traffic and transportation issues to consider in siting

wind energy facilities are largely covered within the General EHS

Guidelines and the Toll Roads EHS Guideline. The main challenge with

respect to wind energy facilities lies with the transportation of oversized or

heavy wind turbine components such as, the blades, turbine tower sections,

nacelle, transformers, and cranes to the site. The logistics, traffic, and

transportation study should assess impacts on existing offsite roadways,

bridges, crossings over culverts, overpasses and underpasses, turning radii,

and utilities, as well as whether surface replacements, upgrades, or

resettlements will be required. To reduce delays to other road users and the

potential for other effects on local communities in the vicinity of the

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proposed route, schedule deliveries outside of peak hours, use only approved

access routes, provide traffic management to stop other traffic where needed,

and provide police escorts where required.

11.5 Solid and Hazardous Waste

Solid wastes need to be collected from dispersed sites and properly disposed

of in a manner consistent with other power plants or facilities. Non

hazardous fluids should be used where possible, and a Hazardous Materials

Waste Plan should be developed if their use can’t be avoided. By performing

major maintenance and repair work off site, certain problems can be

avoided. Ensure that construction wastes are collected from the wind project

site and disposed of at a licensed facility. Waste disposal practices should

not be different in wind power from those required at other power plants or

repair facilities. Anticipate fluid leaks and avoid hazardous leaks by using

non hazardous fluids. Design a Hazardous Materials Waste Plan to address

avoidance, handling, disposal, and cleanup, when necessary. Conduct

turbine maintenance facilities and major turbine repairs off site.

11.6 Air Quality and Climate Impacts

Air quality has a direct impact on human health. Particulate matter in the air,

often as a result of power plant emissions, has been shown to affect

cardiovascular and respiratory health. Construction equipment emissions

would result in localized and temporary air quality impacts during

constructions activities. Unhealthy levels of particle pollution can even

cause otherwise healthy people to get sick. The generation of electricity 72

from the wind does not result in any air emissions. By offsetting more

polluting forms of energy generation, wind energy can actually improve air

quality and our health. A primary benefit of wind energy is the lack of

emission of greenhouse gases or other pollutants. In addition, greenhouse

gases are not emitted in the transportation of fuel to the site, nor are there

risks associated with fuel transported in pipelines. The manufacture and

maintenance of wind turbines does produce some greenhouse gases.

11.7 Socioeconomics and Land Values

Economic impacts to Nebraska are greatest when there are high levels of

local ownership and local manufacturing. The local ownership structure

driven by C-BED Nebraska’s (Community-Based Energy Development) is

popular at present, suggesting that the actual impacts from wind

development in the state may be closer to the high end of the range noted

above if development continues with its current trajectory. However, even in

our low scenarios, wind energy development in the state is expected to

support hundreds or even thousands of jobs for many years into the future.

Finally, creating a vibrant wind industry in the state may allow Nebraskans

the opportunity to capitalize on wind development in surrounding states too.

Nebraska suffers from a declining rural population and, as a result, an

increasing property tax burden on landowners. As the population and tax

base decrease in rural Nebraska, counties increase their property tax rate in

order to produce enough revenue to cover necessary services, which, in turn,

increases the burden on landowners. Wind energy development provides

significant property tax revenue by substantially increasing the property tax

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base, without increasing the current tax rate levied on landowners. As wind

developers invest in rural Nebraska, they supplement county revenue by

paying tax on their wind facilities, related improvements, and the real

property upon which structure the wind turbines sit. Nebraska Legislative

Bill 1048 created the nameplate capacity tax to replace the central

assessment and taxation of the depreciable tangible personal property

associated with wind energy generation facilities. The tower, nacelle, blades

and any other structure which is involved in the actual generation of

electricity is not to be taxed as depreciable tangible property. Real property

upon which wind generation facilities are based is not exempt from property

tax for ex. concrete pads, foundations, operations and maintenance

buildings, road construction, leasehold value, and lease payments. The land

itself will continue to be taxed as it was prior to construction of the tower.

11.8 Archaeological and Cultural Resources

During project design and site development, important cultural and fossil

resource sites should be avoided and protected or else a mitigation plan

should be developed. Special care should be taken to preserve the

confidentiality as well as the integrity of certain sensitive resources or sites

sacred to Native Americans. Identify and avoid potentially sensitive cultural,

historical, or prehistorically resources and involve all stakeholders early on.

Consult with the Nebraska State Historical Society and other qualified

professional specialists familiar with cultural and fossil resources in the

project development area. Some sensitive resources and sites may be

confidential to Native Americans. Respect this confidentiality and work

closely with tribal representatives to protect these resources by avoiding

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disruption to these sites. Design project site layout to avoid sensitive

resources, if possible and prepare a monitoring and mitigation plan for

protection of sensitive resources during construction and operation of the

project. Also, an appropriate mitigation of unavoidable impacts and

monitoring to ensure measures are implemented is required. Lastly, allow

adequate time in the project schedule for data and specimen recovery,

mapping, analysis, and reporting.

13. Grid Interconnection

13.1 Capacity, Voltage and ECC analysis

Through my project area there is a 69kV line 3.5 miles long that’s located in

the bottom right corner of the project area connecting from two substations.

One located just out the project area and the other located with the project

area as displayed in the figure as substation 1 and substation 5. A 69kV line

is a single pole, typically 50-70 feet tower height and a right of way width of

70-100 feet.  Through an interconnected grid of 69kV, power lines and

distribution substations. Hence, the substations are the hub for serving the

neighborhood electrical needs.

Figure 51 displays the 69kV line as a purple line running through the project

area from substation 1 to substation 5. Also, Figures 52 and 52 shows image

of the substations from an aerial view. Due the dirt roads in the project area

Google earth was unable to give a more detail image of the 69kV lines and

substations being that the project area is surrounded by dirty roads.

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Figure 51 - Transmission Line

Figure 52-Substaion outside Project Area

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Figure 53-Substation in Project Area

Furthermore, after locating the transmission lines that run through your

project area it was then possible to calculate the maximum capacity the wind

project can undertake. The power of transmission is then calculated by

determining the voltage, conductor size and its substance. However, the

conductor size chosen for this project is 477 MCM ACSR which acquires an

ampacity of 670 Amps. After gather this information, the calculation to find

the maximum capacity can be determined, using 3 phase current then

multiply it by the transmission line voltage of 69kV, also multiplied by the

Amps of 670 and then multiplied by 0.55 which is the Economic Carrying

Capacity (ECC). Hence, the ECC ranges from 50-55 percentages but for the

project 55 percentages was selected. Lastly, after the calculation of the

maximum capacity was made for this project, the final output was 76.280

kW which is then converted to 76 MW of maximum capacity.

13.2 Loads, System Protection and Conditions

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The manufacturers of wind turbines must ensure that the turbines they build

are certified to withstand extremes of wind speed. A wind turbine must be

built to withstand winds at hurricane speeds. The energy content of wind is

proportional to the cube of the wind speed, so a turbine subjected to high

wind speeds will be under a massive amount of stress. To reduce the impact

of extreme wind speeds without affecting efficiency, wind turbine

manufacturers build the rotors on wind turbines with few blades, which are

as long and narrow as practical. To gain the most productivity from such

narrow blades they are pitched at an optimum angle to the wind. If a turbine

was built with more blades or very wide blades, such as traditional wind

powered water pumps, it would be subjected to incredibly large forces even

at moderate wind speeds. Extreme loads at a particular site are characterized

by measuring maximum wind speeds in each 10 minute period. Because a

wind turbine will be subjected to varying wind speeds, and therefore

fluctuating forces it needs to be able to withstand the varying load. This is

especially the case where a turbine is situated in an area with a turbulent

wind climate. The components of a turbine will be subjected to repeated

bending, particularly the rotor blades. This flexing and relaxing will

eventually cause cracks to appear in the component which can ultimately

lead to the component breaking. Turbine manufacturers are well aware of

metal fatigue, as it is a well known problem which occurs in many different

industries. Because of this, metal is not generally used for rotor blades, as

there are other, more suitable materials which withstand the repeated

flexing.

Furthermore, the transmission system in the State of Nebraska is split

between the Eastern Interconnection and the Western Interconnection, with

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the transmission networks in each interconnection operated and planned

separately. The majority of the geographic area and load in Nebraska is

located in the Eastern Interconnection, served primarily by NPPD, OPPD,

and Lincoln Electric System (LES), and is a part of the SPP regional

transmission organization (RTO). The SPP region shares a border with the

Western Electricity Coordinating Council (WECC) in the west, the MISO in

the north, northeast, and southeast, and the Electric Reliability Council of

Texas (ERCOT) in the south. Nebraska sits right at the border between SPP,

WECC, and MISO. In grid connected systems, the only additional

equipment required is a power conditioning unit “inverter” that makes the

turbine output electrically compatible with the utility grid. Usually, batteries

are not needed. Two basic grid interconnection configurations exist, one

with a battery bank and one without. Grid interconnection allows the option

of net metering which basically allows a turbine owner to be credited for the

surplus electricity produced. Currently in Nebraska, systems up to a 25 kW

capacity can be interconnected to the grid using state net metering laws.

Higher capacity systems can be interconnected under special contracts with

the local utility. Connecting your turbine to the grid will require

coordination with the electric utility and an electrician. Talk to your local

utility before installation to determine electrical requirements needed for

interconnection.

Grid interconnection with no battery backup is the cheapest configuration

and requires the least amount of maintenance. Batteries significantly

increase the project cost and require additional maintenance and storage

consideration. Usually battery banks are stored in small sheds to help

maintain optimal operating conditions. Batteries have the potential to

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produce explosive gas in confined areas, so extra caution and consideration

is necessary for a battery tied system. Battery back-up does make electricity

available if the utility power fails. Wind turbines directly tied to the grid will

not provide electricity to the owner in the event of a power outage.

14. Permitting

14.1 Federal, State and Local

Several permits and approvals are required to build wind projects. Due to the

lack of combustion in the generation of wind energy, air emission and water

discharge issues are virtually nonexistent. In general, local permits and

approvals, especially regarding zoning compliance, become critical path

issues. Visual impacts and impacts to local and migratory bird populations

are also an important issue to address. All of the federal, state and local

permits or approvals that are generally required of electric generating

facilities were identified, and their applicability to wind energy. While the

list is extensive, the NPA does not believe that permitting, which is a normal

process involved for any power resource project, will be a major problem in

the development of wind farms in Nebraska. However, the public policy of

Nebraska for building generation and transmission facilities in Nebraska is

an issue that will need to be addressed.

The Nebraska Power Review Board (NPRB) must authorize the

construction of any type of power generation facility in the state of

Nebraska, including wind turbine generators, the output of which is sold at

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either retail or wholesale in Nebraska. The application for authorization

consists of a questionnaire requesting a description of the proposed facility

including the identification of alternative locations and unit types, overall

project schedule and total estimated costs. The NPRB examines the

application upon filing and holds a public hearing to discuss concerns and to

discover any issues from the public or alternative generating sources such as,

already functioning power suppliers in the area. The applicant has the

opportunity to answer all questions and to resolve all issues of concern from

parties contesting the application. Under the Nebraska Revised Statutes,

section 70-1024 (http://www.nebraskalegislature.gov/laws/statutes.php?

statute=70-1024), the NPRB must find that the project will serve the public

convenience and necessity before approving any generation or transmission

project.

There is a serious legal question as to whether generation or transmission

facilities sited in Nebraska to serve the export market would meet the public

convenience and necessity criteria. Another regulatory process that may

have to be addressed for the successful creation of an entrepreneurial public

entity in Nebraska, and one which is unfamiliar to public power entities in

Nebraska is a requirement for permission from the Federal Energy

Regulatory Commission (FERC) to be an exempt wholesale generator

(EWG). EWGs are a designated class of independent power producers

created under the 1992 Energy Policy Act. A EWG is defined as a person or

entity determined by FERC to be engaged directly or indirectly and

exclusively in the business of owning or operating an eligible facility and

selling energy at wholesale.

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14.2 Land Use and Building Permits

The amount of land required for a large wind project varies depending on the

terrain and the final layout of the turbines. A rough rule of thumb is that we

can site 2 to 4 turbines per square mile and still provide adequate exposure

to the wind, proper setbacks from homes and roadways, and appropriate

spacing between turbines. The exact density of the turbines does depend on

local topography, leased land contiguity, environmentally sensitive areas,

and local zoning regulations, amongst other factors. Actual land used by the

turbine is quite small, generally occupying less than a quarter acre. The

majority of the foundation is underground and the concrete pedestal on

which the turbine sits is approximately 20 feet square. A small amount of

additional land is needed for access roads.

Additionally, an owner is ultimately responsible for any development or

construction on their property. In most cases, owners pass the responsibility

of a project to a general contractor or designer to manage and coordinate a

development or construction project. State Law also has requirements that

dictate the involvement of registered professional engineers and architects

for commercial projects. It is suggested that owners monitor the progress of

a project through their professionals to ensure the proper steps are being

followed for design, permitting and inspections. Any pertinent information

an owner can provide design professionals prior to preliminary design will

aid in the success of obtaining a permit. Failure to submit complete

information during any phase of design, permitting or construction can cause

delays in issuing permits, performing inspections, and obtaining certificates

of occupancy.

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15. Land Agreements, Land Owners Consideration

15.1 Terms, Rights and Compensation

A typical full Wind Lease or Easement Agreement compensates landowners

in both phases of a project, the Development or Study Phase and the

Operations Phase. The Development Phase which is the initial term can last

between 2 and 5 years. If the project is not built by the end of this phase, the

typical Lease Agreement is terminated. Attention needs to be focused on the

length of study and evaluation periods, and the termination words to ensure

that the landowner’s expectations are managed with regards to project

development term and project COD, and control of wind rights. The

amounts paid for study phases typically compensate landowners annually on

a per acre basis, however payment structures can vary with one time

payments also offered.

In addition, the operations phase which is after facility is built. Once the

wind farm is in operation, the operations term begins and ranges from 35 to

50 years. Operations and Royalty payments can follow two basic structures

and the minimum royalty is also common. Paid as a dollar amount per MW

of production on annual basis and usually applied in combination with

number of percentage royalty is also common. This is typically in addition

to the minimum royalty and acts as an “inflation” and production risk

insurance for the landowner. Royalties for projects typically built across the

range from 2%-4% of gross revenue produced from the wind farm driven

primarily by the development costs, risks and the market rate for power in

that region. Percentage royalties typically have a built in inflation

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adjustment for the landowner, for the PPA price typically escalating each

year and the total payment to the landowner is the product of the PPA price,

the average turbine production and the number of turbines the landowner is

hosting. Additional payments paid to landowners may involve crop damage

payments, access road payments, transmission and collection line payments,

construction staging and lay down area payments, substation payments, and

payments to alter irrigation devices and pivots

15.2 Royalty, Indemnification and Reclamation Provisions

Property owners enter into private contracts or leases with the wind

developer. Annual rent varies and is generally based on wind resource,

capacity and number of turbines. In some cases, land owners form

associations where there is an agreement to all receive the same payment

and may be agreements for those who are part of the association, but who do

not actually have turbines located on their property, to also receive

payments. Also, an indemnity which is an agreement between two parties in

which one agrees to secure the other against loss or damage arising from

some act or some assumed responsibility. In the context of customer-owned

generating facilities, utilities often want customers to indemnify them for

any potential liability arising from the operation of the customer’s

generating facility. Although the basic principle is sound, utilities should not

be held responsible for property damage or personal injury attributable to

someone else. Indemnity provisions should not favor the utility but should

be fair to both parties.

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15.3 Public Outreach

Wind projects with continuing public outreach efforts tend to generate

greater public support. Beginning public outreach early in the planning

phase and continuing throughout the life of a project will likely contribute to

the ease with which a project is carried out in subsequent phases. Public

outreach also helps develop a public that is informed about the specifics of

the project as well as the tradeoffs associated with different energy

developments. Involving the public in the planning process, asking for and

then making use of input, and answering questions early and often can help

appropriately and proactively address concerns. At the same time, working

with a community that is informed or educated about the issues, but does not

yet have a firm opinion on a specific project may be ideal, but that is rarely

the case. More often, some individuals in a community have diverse levels

of knowledge and opinions on a project or policy. Ongoing outreach and

community engagement can reach broader segments of a community who

may not have yet formed an opinion and who are quietly waiting to learn

about how a wind development might impact them, positively or negatively.

Special efforts must be made to reach out to members of the community who

may be less engaged or less vocal in order to assess the true sentiments of a

community. Public outreach and engagement can’t use an all for one

approach; rather, it must be iterative which can be costly and time

consuming, but is often necessary for a successful wind project.

16. Construction

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16.1 Collection Lines, Service Roads and Logistics

As displayed in figure 54 the collector system is a series of underground

electric cables that run from each turbine to the electrical substation. Which

are colored coordinated to illustrate the size of the lines, whereas, the blue

lines represent 500 MCM ACSR underground cables and the orange lines

represent 1000 MCM ACSR underground cables. Typically, a series of

turbines is interconnected to create a circuit rather than having a direct cable

from each turbine to the substation. At Cornhusker’s Wind Estate there are a

total of 6 circuits. This is a drawing of a circuit that’s connecting 3-5

turbines per circuit and sends the electrical output to the substation as

displayed in figure 54 as purple icon located almost in the middle wind farm

using a 4/0 overhead cable system displayed as green lines from each circuit.

Furthermore, before construction of the wind turbines begin, access roads

must be constructed. The access roads run from existing roads to the turbines

sites. The access road design must be wide enough so that the large vehicles

used for bringing parts of the wind turbine and the crane used to erect the

wind turbines are able to travel easily. For this project, the roads must be

strong enough to withstand a great number of loads. In an attempt to try

reducing the environmental impacts due to water runoff, the access roads are

unfinished roads made up of processed gravel on top of a stabilizing geo-

textile fabric. Proper design and construction of the access roads is vital to

this project, extra cost will be incurred if there are problems transporting

supplies to the wind turbine sites.

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Figure 54 - Collection System

16.2 Contracting and Building Site

During the construction period there will be jobs created. However,

construction may be completed by crews that are not from the area, or by

subcontractors in the area. The process includes building access roads,

turbine foundations, and construction of electrical infrastructure to collect

and distribute the energy being produced. The turbine components are

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shipped into the site and erected. Once the turbines are erected and

commissioned, the project site is restored and wind farm operation begins.

However, these workers can bring a temporary boost to the economy when

they purchase goods and services, rent hotel rooms, and eat in restaurants.

17. Post Construction Monitoring and O&M

Post construction surveys and monitoring studies, including monitoring for

carcasses and conducting surveys such as, breeding bird, nesting raptor,

prairie grouse, and bat acoustic surveys should be conducted to determine

the estimated direct and indirect impacts of the wind farm. These data are

essential for both identifying potential measures to mitigate the impact of

operations at existing sites as well as assessing potential risks associated

with future developments. In general, post construction surveys and

monitoring of birds and bats and other relevant species should be conducted

for a minimum of two years following initiation of project operations.

However, longer term monitoring is encouraged and would provide more

reliable data. Furthermore, operation and maintenance jobs will be created

and continue over the long term. There are local training programs for these

jobs that could mean hires would be of local workers. Once the wind project

is operational, it must be maintained for its lifespan by a qualified firm.

Operating costs also include warranties, administrative fees, insurance,

property taxes, land lease payments, and a contingency fund for unforeseen

problems. How well you maintain your turbine will affect your project’s

lifetime and return on investment. After the useful lifetime of the turbine,

decommissioning costs will be incurred for removal of the machines and

restoration of the site.

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18. Project Lifetime, Decommissioning and Remediation

The components of a wind turbine are typically designed to remain

operational for twenty years. It would be quite easy, and hardly any more

expensive to design and build some of the components to remain operational

for far longer. However, because most of the major components would be

very expensive to build for a longer life span, it would be a waste to have a

whole turbine standing idle because one part failed years earlier than the

rest. Furthermore, In the event of default, or termination of a lease

agreement, the landowner should specify how much time the wind developer

is permitted to remove the wind turbines from the land. Payment must also

be established during this time period. The landowner must also specify any

increased payment or obligations in the event the wind developer neglects to

remove the wind turbines in the specified period of time.

In order to prevent the wind developer from simply walking away from the

project, the landowner should demand a “decommissioning security,” to be

established as soon as the wind turbines become operational. This security is

generally a specified amount of money which is put aside by the wind

developer to ensure there is sufficient funding available for removal and

reclamation at the end of the project. Typically, the operational life of a wind

turbine is about 20 to25 years. Once electricity production is reduced, an

assessment must be made as to when the facility will be decommissioned.

Decommissioning must be outlined at the planning and design stage. Issues

to be addressed include the removal of above ground structures and

equipment, landscaping or reinstatement of roads and vegetation, as well as

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measures for the restoration of the environment to its original state to the

greatest possible extent. Each case is different, depending on the size of the

development and geographic properties of the locality.  

19. Conclusion

Constructing a wind farm on involves environmental, public opinion, legal,

economic, and safety issues. The research for this report shows that none of

these concerns will impede the development of wind energy on the proposed

site. The community affected by this project supports its development, and

they would benefit from its economic and educational value. Wind energy is

clean, renewable, and local. The report proves that the Cornhusker’s Wind

Estate is feasible, and encourages investors in its development. This project

presents investors with an ideal opportunity to be an environmental leader

and to educate the public about the importance and value of renewable

energy.

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