WEPS and Marble Head Wind Feasibility AWEA03

8/3/2019 WEPS and Marble Head Wind Feasibility AWEA03

1/18

Massachusetts Wind Energy Predevelopment Support

Program

&

Feasibility Study for Marblehead, Massachusetts

Mia [email protected]

Brendan [email protected]

Tony Ellis, Tony Rogers, Sally Wright, and James Manwell

Renewable Energy Research LabCenter for Energy Efficiency & Renewable Energy

Department of Mechanical Engineering

University of MassachusettsAmherst, MA 01003 USA

www.ceere.org


2/18

Wind Energy Predevelopment Support Program

ABSTRACT

The Renewable Energy Research Lab (RERL) at the University of Massachusetts,Amherst has launched a new program to aid individuals and community groups inperforming the preliminary steps leading toward the implementation of a wind energyproject. RERL has provided community wind energy support for 20 years and hasrecently consolidated these services into a program called Wind Energy PredevelopmentSupport (WEPS). This program is a model for encouraging community-based winddevelopment that has received enthusiastic support throughout the state. A description ofthe WEPS program is presented in this paper, along with the summary of a wind energyfeasibility study for a community in Massachusetts.

WIND ENERGY PREDEVELOPMENT SUPPORT

NEED FORPREDEVELOPMENT SUPPORT

As with any energy facility, the integration of wind energy into the electrical power gridrequires a great deal of planning, coordination, and engineering and involves stakeholdersfrom many public arenas.

A wind energy project timeline can be divided into two phases: development and pre-development. The predevelopment phase of a wind project includes monitoring andevaluating the local wind resource, determining possible turbine locations, and estimatingthe economic feasibility of a wind project. It may also include gathering local support,public education and outreach, securing legal rights to land and access to power lines.The predevelopment phase may last 1 to 2 years and requires a considerable amount oftime and resources.

The beginning of the development phase is the point where a decision has been made topurchase and install a wind energy system and sufficient financing has been obtained toproceed. Often, a private developer is hired at this time if they have not already beeninvolved in the predevelopment process. The developer or subcontractor will perform thedetailed design and engineering of tower foundations, road access, electrical gridconnections, and will oversee the installation and commissioning of the project.

For large wind farms, one wind development company may perform both thepredevelopment and development functions. However, for the installation of a single orsmall cluster of turbines, a wind developer may find the overhead cost of predevelopmenttoo risky for the potential return. In these cases, the burden of predevelopment can betaken on by a community entity, such as the local utility, non-profit organization, or

landowner. While these groups are often interested in developing wind power, they maylack the capital and the expertise to perform these predevelopment tasks.

RENEWABLE ENERGY RESEARCH LAB - MEETING COMMUNITY NEEDS

The Renewable Energy Research Laboratory (RERL) at the University of Massachusettsserves New England as a source of wind energy expertise. Along with the Massachusettsstate energy office, the Department of Energy Resources (DOER), RERL has been

AWEA 2003 Devine, OConnor, Ellis, Manwell, Rogers, Wright Page 2


3/18


4/18


o Analysis of data, energy production projectionso Use of SODAR where appropriate and possible

Other technical follow-up supporto Economic & feasibility estimateso Electromagnetic Interference (EMI), noise

o Conceptual layouts, visualizationso Development of technical bid specification and request for proposals; bid

evaluation

TECHNICAL ASSISTANCE

WEPS support is provided by staff engineers and graduate students at RERL. Technicalassistance can include wind data gathering and analysis, visualizations, and soundmeasurements.

Wind Data Analysis

Prospective sites will typically be monitored for one year, depending on the results and

magnitude of the project. The raw wind data that is collected at the monitoring site issent to RERL for processing.

At RERL, the data is validated for completeness and accuracy, and erroneous data isremoved. For example, the screening process will find errors due to damaged sensors,data logger malfunctions, broken wires, or icing conditions. All of the 10-minute windresource data that is collected and verified will be available to the public on the RERLwebsite (www.ceere.org/rerl) after it has been checked for quality control.

Using the validated data, a basic analysis is performed and a report is presented to theparticipant, which includes a summary of the following items:

Wind characteristics: The wind is characterized by average speed, primary direction,

and turbulence intensity. These parameters are used in further evaluations.Long term wind-speed estimates: In order to determine if the measured year was atypical year or if it was unusually windy or calm, the data must be compared to long-term measurements taken at a nearby location. In eastern Massachusetts, RERL usesmeasurements from Bostons Logan International Airport and RERLs monitoringtower at Thompson Island in the Boston Harbor. In western and centralMassachusetts, long-term data is available from RERLs wind turbine on Mt. Tom inHolyoke. Locations such as weather stations or other local data sites are used asappropriate.

Estimated Power Production: Using power curve specifications from wind turbine

manufacturers, the 10-minute wind speed data can be used to estimate powerproduction and annual energy production. With this information, the community willhave an estimate of the amount of electricity they can expect from selected windturbines.

Other data analysis can be performed if needed, such as estimating the wind speeds at alocation other than where the measurements were taken.

http://www.ceere.org/rerlhttp://www.ceere.org/rerl


5/18


Economic Analysis

General price guidelines and information from turbine manufacturers are used to estimatethe cost of installation and maintenance of the wind turbine project. Local electricityrates, interest rates, and discount rates are used to estimate the cost of energy andpayback of the system.

VisualizationsOne of the most common barriers to community acceptance is the visual impact of thewind turbine(s) on the landscape. To address this concern, RERL creates computersimulations of what the actual wind project will look like. These visualizations arecreated with the use of topographical maps and the WindFarm software package[ReSoft Ltd.] to give the most realistic view possible.

Noise Measurements

Another common cause for community concern is noise created by the wind generatorand rotating blades. When appropriate, RERL arranges for measurement of backgroundsound levels in the area around the potential turbine site. Using sound data supplied bythe turbine manufacturer, RERL estimates the extent to which an increase in noise levelswill affect those in the area of the proposed site.

Equipment Used

The WEPS program uses standard wind-monitoring equipment, including 40 or 50-metertowers, anemometers, wind vanes, and data loggers. Fifty-meter towers are required inwooded areas and complex terrain. Other equipment may be used where appropriate.For instance, additional monitoring of sites may be undertaken using RERLs SODAR(Sonic Detection and Ranging), which permits wind speeds to be measured at heightsgreater than 40 meters without the use of a tower (Figure 1). In remote sites a cell phonelogger may be used and back-up sensors will be installed on the towers. RERL willprovide assistance in permitting the installation of the monitoring tower and equipment.

RERL will install, maintain, and dismantle the tower at the end of the monitoring phase.

Figure 1. Sonic Detection and Ranging (SODAR) Equipment



6/18


COMMUNITY ASSISTANCE

The success of a wind energy project depends on community involvement and support aswell as legitimate technical data. During the wind-monitoring period, RERL staff willwork with community participants to determine the level of local interest and to identifyany potential barriers to wind power development. This includes participation in town

meetings, educational workshops, and communicating with utility representatives or localofficials.

A wind energy project must comply with federal, state, and local regulations. InMassachusetts, this may include permits and approvals from the Energy Facilities SitingBoard, Department of Environmental Protection, Coastal Zone Management Office,Natural Heritage Program, Army Corps of Engineers, and the Federal AviationAdministration [National Wind Coordinating Committee, 1998].

Other potential barriers that may adversely affect a community wind project include landownership or zoning issues, public acceptance issues, safety issues if the turbine is to belocated in populated areas, and interconnection to the power lines.

If a community decides to proceed, the final stages of predevelopment include solicitingbids from wind turbine manufacturers. The prospective turbine owner must specify theirneeds and prepare a detailed request for proposals (RFP).

To the extent possible, RERL will assist the community in navigating each of theseprocedures and guide the community in dealing with regulators and developers frompredevelopment through project installation.

APPLICATION PROCESS

Applicants are solicited through public outreach channels, including the media, theInternet, and brochures distributed at energy conferences and events. Participation in the

program is free for selected applicants. Participants will typically contribute their time bytaking an active role in the installation and maintenance of the equipment to the extentpossible.

Selection Criteria

The WEPS program is directed towards towns, landowners, small businesses,municipalities, farms, non-profit organizations, and public agencies. Participants will bechosen based on several criteria:

Size: The focus of the program is to encourage the development of sites that couldsupport a small number of utility-scale wind turbines.

Location: An attempt has been made to encourage wind power in diverse regions ofMassachusetts.

Likely wind resource: Identification of the potential wind resource will initially bebased on the wind maps prepared under the Southern New England wind resourcestudy funded by a consortium of Northeast Utilities, Massachusetts RenewableEnergy Trust Fund and the Connecticut Clean Energy Fund (Figure 2). Areas that areshown to have a poor wind resource based on the initial evaluation will likely not beaccepted.



7/18


Source: True Wind Solutions

Figure 2. Wind Resource Map of Massachusetts

Participant: Preference will be given to municipalities, non-profits, landowners,public agencies and farms. RERL will attempt to involve participants of varyingtypes and categories, within the constraints of the other criteria.

Preparation: Preference will be based on the extent of the applicants preparatory

work, as demonstrated by the completeness of the application.Other criteria include: proximity to transmission lines, land ownership, and communitysupport.

After applicants pass an initial screening based on the criteria discussed above, RERLconducts phone interviews and/or site visits to make the final selection. The initial roundof monitoring sites has been selected for 2003, which include two municipal utilities, onewater treatment plant, one town, two private landowners, and a non-profit organization.Applications will be taken on a rolling basis for future consideration.

WEPS Conclusions

The grass-roots nature of community-scale wind projects requires the collaboration of

many parties. The existence of unbiased technical and practical information, like thatprovided by RERL, will help to facilitate the decision-making process. The Wind EnergyPredevelopment Support program is an innovative and replicable model that connectscutting-edge technology and educational opportunities with community participation anddevelopment.



8/18


FEASIBILITY STUDY: MARBLEHEAD, MASSACHUSETTS

As an example of the scope of assistance that the Renewable Energy Research Lab(RERL) provides to communities, a summary of a feasibility study for Marblehead,Massachusetts is presented below.

BACKGROUND

Town of Marblehead

Marblehead is located on the north shore of Massachusetts. It covers 4.5 square mileswith a population of 20,000. Marblehead has a peak electric demand of 25,500 kW andconsumes approximately 105 GWh per year. Distribution lines are rated at 4,160 volts,with 13kV transmission lines. Most circuits are designed at 1 to 1.5 MW. Several dieselgenerators distributed around the town provide 6 MW of peak generating capacity. TheSalem Harbor Power Station is the primary supplier of electricity to the area.

Interest in Wind Power

Recently, the Salem Harbor Power Station, a coal-fueled power plant located about 2

miles to the northwest of Marblehead, was declared one of the five dirtiest power plantsin Massachusetts and the dirtiest plant operated by Pacific Gas & Electric[Greenpeace, 2003]. Marblehead was highlighted in the April 2003 issue of BostonMagazine as ranking low on the list of healthiest towns in Massachusetts. It states,"What's unexpected are the sky-high rates of asthma and some types of cancer, whichresearchers at the Harvard School of Public Health attribute to pollution from the SalemHarbor Station power plant [Blanding, 2003]. In response to pollution-related heathconcerns such as this, the citizens group HealthLink was formed in Marblehead. Inactively seeking solutions to energy-related pollution, HealthLink is investigatingrenewable energy options.

In addition, the Marblehead Municipal Light Department (MMLD), a town-owned

municipal utility, became interested in the potential economic benefits of wind energyand the ability of wind to diversify their energy portfolio after the successful wind turbineinstallation in Hull, MA [McGowan, 2003].

Role of the Renewable Energy Research Lab

In 2001, HealthLink requested the services of the Renewable Energy Research Lab(RERL). After discussing the potential benefits and challenges of wind energy withMarblehead representatives, the decision was made to analyze the feasibility of a windproject. With the assistance of MMLD, permits were obtained to mount wind-monitoringequipment on top of an existing cellular tower located at the town landfill. RERL hascollected over a year of data from this site.

Based on the year of wind data collected at Marblehead, the results of the feasibilitystudy are presented below.

DESCRIPTION OF POTENTIAL WIND TURBINE SITES

As Marblehead is densely populated, siting of a wind turbine is a critical issue. Twopossible wind turbine locations are investigated in this paper: the town landfill and thepublic beach parking lot, as described below. Due to the land constraints of both sites,



9/18


only one machine is considered for either location. A computer generated wind energyresource map of Southern New England has been made by TrueWind Solutions. Thesection of the map around Marblehead is shown in Figure 3.

6.5 - 7 m/s

7 - 7.5 m/s

Source: TrueWind Solutions

Figure 3. Wind Resource Map of Marblehead, MA

Town Landfill: The anemometry equipment is currently located on a cell tower at theedge of the landfill. The wind map suggests that the average wind speed at a height of 65meters (213 feet) above ground ranges from 6.5 to 7 meters per second. Soil instabilitymay make a turbine foundation more expensive than a typical installation at this site.

Possible turbine location

Figure 4. Landfill Site as Viewed from Top of Cell Tower

Public Beach: The public beach is located on the southeast part of town along thewaterfront. The exact wind potential at this site is unknown, but the wind map inFigure 3 suggests that the beach site could have a wind resource from 6.5 to 7.5 m/swinds at a 65-meter height. A turbine could be located in the southwest corner of theparking lot.



10/18


MEASURED WIND RESOURCE

On March 1st, 2002, wind resource monitoring equipment was installed atop the 55-meter

(180-ft) cell tower at Marbleheads landfill. It consisted of a primary and secondary pairof anemometers and wind vanes, along with a data acquisition unit. A specially designedpole and base was needed to mount the equipment on the tower as shown in Figure 5.

The data loggers are programmed to sample the wind speed every second and record theaverage 10-minute wind speed, standard deviation, maximum and minimum values.These ten-minute averages are periodically sent to RERL to be inspected forcompleteness and accuracy. For this report, the 10-minute averages were converted tohourly averages, which are more manageable for energy calculations.

Figure 5. Wind Monitoring Equipment at Top of Cell Tower

Quality Control and Data VerificationTwo sets of anemometers and wind vanes were used to measure wind speed and directionat the Marblehead site. Redundant equipment is used to ensure that measurements areaccurate and to serve as a back-up.

Figure 6 lists the percent of missing data for each month. The total data recovery ratewas 97%. Throughout the summer, frequent dropouts of data occurred, possibly as theresult of electro-static discharge (ESD). In late July, a lightning strike damaged thelogger. The data card and two SIM (analog to digital converter) cards were replaced onAugust 2, 2002. In addition, surge absorbers were wired into the anemometers toincrease resistance to future ESD damage. These adjustments have minimized datadropouts.

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

0.0% 0.0% 0.3% 8.3% 1.1% 12.2% 8.7% 4.8% 0.1% 0.0% 0.0% 0.0%

Figure 6. Percent of Data Missing for Each Month

In order to make hourly predictions of energy production throughout the year, anymissing data in hourly wind speeds, due to either sensor failure or the removal oferroneous data, was approximated. Gaps were filled using a statistical technique



11/18


developed by the University of Massachusetts based on the short-term fluctuations in thewind and diurnal trends. Wind speeds were generated that would closely match expectedvalues without changing the average wind speed or standard deviation of the data set.

Calculations performed in this report use the complete hourly data set, includingsynthesized gap-filled data, from March 1, 2002 through March 1, 2003.

Wind Characteristics

The winds are relatively steady throughout the day. They are strongest during thedaylight hours, peaking in the afternoon at approximately 6.8 m/s. As indicated inFigure 8, the primary wind direction is from the Northwest.

Average Wind Speed 5.84 m/s 13.1 mph

Max Hourly Wind Speed 17.1 m/s 38.3 mph

Max Gust 29.4 m/s 65.8 mph

Standard Deviation 2.54 m/s 5.68 mph

Turbulence Intensity 0.22Figure 7. Measured Wind Speed Characteristics for Marblehead

Figure 8. Seasonal and Annual Wind Rose (Percent of Time)

WIND RESOURCE PREDICTIONS

In order to make useful predictions about the feasibility of a wind project in the area,some modifications to the wind data file must be made. To determine the energyproduction of the various candidate turbines, the wind speed distribution at each turbinehub height, was calculated. The data collected at Marblehead did not include a measureof the wind shear; therefore, the log law mathematical model was used to estimatechanges in wind speed with height assuming a surface roughness length of 0.30.



12/18


In addition to the height adjustment, a modification is made to account for variations inannual wind speed trends. A Measure-Correlate-Predict (MCP) method is used to predictlong-term wind speeds based on short-term measurements. Short-term measurements aretaken at the proposed turbine location and compared to long-term measurementsavailable at a nearby location. In this report, five years of wind speed data from Logan

International Airport in Boston were compared to the one year of Marblehead data. Itwas determined that the average annual wind speed at the landfill location is 5.70 m/s,which is slightly slower than the measured 5.84 m/s. Therefore, all of the hourly windspeeds were adjusted downward by a factor of 0.976 to reflect a lower long-term averagewind speed.

The results of both the height and long-term adjustments are shown in Figure 9. Theadjusted average of 5.70 m/s at a 55-meter height is a fair to moderate wind speed forpower production. Wind speeds are expected to increase with increased wind turbine hubheights. Therefore, taller turbines will likely produce more electricity.

Tower Height (m) 55 60 65 70 75 80 90

Wind speed (m/s) 5.70 5.81 5.90 5.98 6.04 6.13 6.26

Figure 9. Long-Term Average Annual Hourly Wind Speed at Hub Height

CANDIDATE TURBINE CHOICES

Candidate turbines were selected based on a number of criteria, including proven designconcepts, established business presence in the U.S., operational reliability, and safety.

Manufacturer

(Model)

Power

Rating

Rotor

Diameter

Tower

Height

Power

Regulation

Generator

Operation

GE (GE1.5sl, 80) 1.5 MW 77 m 80 m Pitch Variable speed

GE (GE1.5sl, 65) 1.5 MW 77 m 65 m Pitch Variable speed

Vestas (V47) 660 kW 47 m 65 m Pitch/OptiSlip 2 speed

Vestas (V80) 1.8 MW 80 m 80 m Pitch/OptiSlip 2 speed

Nordex (N62) 1.3 MW 62 m 70 m Stall 2 speed

NEG-Micon (NM72c) 1.5 MW 72 m 80 m Active-Stall Constant speed

MADE (46/660) 660 kW 46 m 70 m Stall 2 speed

Bonus (62/1300) 1.3 MW 62 m 60 m CombiStall 2 speed

Figure 10. Characteristics of Candidate Wind Turbines

Eight turbines from six companies made the initial screening with capacity factors greaterthan 16%. The selected turbines differ in power rating, dimensions, power regulation(pitch or stall), and generator operation (fixed or variable).

ESTIMATED POWERPRODUCTION

The long-term hourly hub height wind speeds are used with the power curves of eachwind turbine to estimate the annual electricity they would produce. The power curveinformation, which is usually supplied by the turbine manufacturer, shows the predicted



13/18


performance of the turbine at each wind speed. Summing the power production for everyhour of the year will give the total possible power production. These results are thendecreased by 3% to assume 97% turbine availability as shown in Figure 11.

GE1.5sl,

80m

GE1.5sl,

65m

Vestas

V47

Vestas

V80

Nordex

N62

NEG-

M72c

MADE

(46/660)

Bonus

(62/1300)

2,981,476kWh

2,703,066kWh

1,042,029kWh

3,082,276kWh

1,786,492kWh

2,557,735kWh

910,868kWh

1,809,495kWh

23.2% 21% 18.4% 19.9% 16% 19.9% 16.1% 16.2%

Figure 11. Estimated Annual Power Production and Capacity Factors

The Vestas V80, the machine with the largest rated power (1.8 MW), would produce themost electricity, followed by the GE 1.5 MW machine. Both are on 80-meter towers andare optimized for moderate wind speeds with large rotor diameters. Of the smallermachines (less than 1 MW), the Vestas V47 out-performs the MADE 46/660.

ECONOMIC EVALUATIONThe economics of the candidate turbines are compared against each other based on thevalue of the electricity produced, estimated turbine cost, installation cost, O&M costs,electricity cost inflation rate, general inflation rate, and the discount rate.

Capital and Installation Costs

Turbine capital costs were either taken from published manufacturer's list prices orinformation supplied directly by the manufacturer. In cases where quoted prices were notavailable, general benchmark guidelines were used. The numbers assume a typicalinstallation, which includes a foundation, transformer, grid hookup, installation,transportation, roadwork, and remote monitoring equipment. The Marblehead

installation costs may be more or less expensive depending on the exact details of thefoundation, road design, grid hookup, etc. The prices are summarized in Figure 12.

Turbine

Costs

GE1.5sl

(80m tower)

GE1.5sl

(65m tower)Vestas (V47) Vestas (V80)

Capital:Installation:

Total:

$1,245000$315,000

$1,560,000

$1,155,000$290,000

$1,445,000

$487,500$162,500$650,000

$1,350,000$450,000

$1,350,000

Turbine

CostsNordex (N62)

NEG-Micon

(NEGM72)MADE (46/660)

Bonus

(62/1.3MW)

Capital:

Installation:Total:

$950,000

$250,000$1,200,000

$1,125,000

$375,000$1,500,000

$581,625

$193,875$775,500

$1,145,625

$381,875$1,527,500

Figure 12. Project Costs

Value of Electricity Produced

The value of electricity produced by the wind turbine depends on the market in which itcan be sold and various production-based incentives. Renewable energy credits (REC),which are based on the Massachusetts renewable portfolio standard, allow the



14/18


environmental aspects of renewable energy to be sold in the competitive market. TheRenewable Energy Production Incentive (REPI) is a federal incentive that is currentlypart of legislation but is subject to change over the 20 years of the project [MA DOER,2001]. In this paper, it is assumed that the price of electricity for the municipal utility is$0.05/kWh, the renewable energy credits can be sold at $0.025/kWh, and the REPI is

available at $0.018/kWh. Therefore, the total revenue is taken as the sum of the marketprice of electricity and production incentives, or $0.093/kWh.

Baseline Turbine Life Cycle Ranking

A lifecycle cost analysis, using software developed at the University of Massachusetts[UMass Wind Energy Engineering Minicodes], has been performed for each of themachines. Based on previous experience, Figure 13 lists the assumptions that are used inthe baseline life cycle analysis [Manwell et al, 2003]. The non-financed portion of thefirst cost is assumed to be made at the beginning of the first year. All annual expensesand receipts are assumed to occur at the end of each year.

Economic Life 20 years

Down Payment 15%Loan Interest Rate 7%

Discount Rate 4.25%

Electrical Inflation Rate 2.7%

General Inflation Rate 2.7%

Price of Electricity $0.093 /kWh

Loan Period 10 years

Annual Cost 1.8% of installed cost

Figure 13. Baseline Values for Economic Analysis

Using these baseline values as input to the life cycle costing program, the candidateturbines were evaluated, and results are summarized in Figure 14.

Turbine ModelGE1.5sl

(80m tower)

GE1.5sl

(65m tower)

Vestas

V47

Vestas

V80Nordex N62

NEG-Micon

M72MADE46 Bonus1.3

Installed Cost $1,560,000 $1,445,000 $650,000 $1,800,000 $1,200,000 $1,500,000 $775,500 $1,527,500

Present Value ofTotal Costs

$2,228,052 $2,063,805 $928,355 $2,570,829 $1,713,886 $2,142,358 $1,107,599 $2,181,634

Levelized Cost ofEnergy ($/kWh)

$0.056 $0.057 $0.067 $0.063 $0.072 $0.063 $0.091 $0.091

Net Present Valueof Savings

$2,528,083 $2,248,203 $733,920 $2,346,105 $1,135,976 $1,937,813 $345,444 $704,924

Simple payback(years) 6.3 6.4 7.6 7.1 8.3 7.1 11.0 10.8

Figure 14. Baseline Economic Evaluation

The GE1.5sl (80-meter tower) wind turbine has the shortest simple payback of 6.3 yearsand lowest levelized cost of energy ($0.056), followed by the NEG-Micon and VestasV80, each with a simple payback of 7.1 years and levelized cost of energy of $0.063.



15/18


Sensitivity Analysis

To determine the relative sensitivity of the outputs to the initial assumptions, the lifecycle costing program was re-run with one of the turbines, the Vestas V47, which wasevaluated to be in the middle of the pack. The range of input values was varied by oneparameter at a time such that the lifecycle analysis produces a net savings approximately

equal to zero. This will indicate at what point the turbine becomes uneconomical tooperate. The zero savings values, along with the baseline values, are listed in Figure 15.

Price of Electricity

Discount Rate

General Inflation Rate

Electricity Inflation Rate

Initial Cost 179%

$0.093

4.3%

2.7%

2.7%

100%

$0.052

26%

17%

-4%

609%

618%

240%

79%

Baseline

Assumption Value

Zero Savings

Value

Percent Change in

Baseline Assumptions

44%

Figure 15. Values that Produce No Net Savings (Vestas V47)

The economic analysis is most sensitive to the price of electricity. The price that wouldbring the project to zero savings is $0.052. This price could occur if the REPI or RECwere not available.

It should be noted that the Vestas V47 is the third lowest ranked turbine in the baselinecase, with a net savings of $733,920. All other higher-ranking machines would eachhave a larger range before they would produce a net savings of zero.

PUBLIC ACCEPTANCE HURDLES

The installation of a new wind turbine involves a number of environmental, regulatory,grid interconnection, and public acceptance issues. Issues related to permitting arebeyond the scope of this report. Major public acceptance hurdles include visual impact,noise, and avian interaction.

Visual Impact

Photo simulations are used to present accurate representations of a proposed wind turbinein a particular location to help facilitate discussions on a wind projects impact on thelandscape. Photographs were taken at various vantage points throughout Marblehead,and locations of each were documented using a Global Positioning System. Usingdimensions of each wind turbine and digital elevation maps (DEM) from MassGIS[Massachusetts Geographic Information System], the software program WindFarm[ReSoft Ltd] was used to superimpose a turbine in the proper location and scale on each

photo. Examples of the visualizations for the landfill and beach are shown in Figure 16and Figure 17, respectively.



16/18


Figure 16. Visualization of Landfill Site from the North

GE1.5sl80m tower

Figure 17. Visualization of the Beach Site

Any wind turbine model at any tower height will be visible on the landscape as viewedfrom across the Marblehead Harbor and in the immediate vicinity of the machine.However, foliage and the hilly landscape will obscure the view of a wind turbine frommost vantage points throughout Marblehead.



17/18


Noise

Sound generated from the proposed wind turbine is an important issue because of thedensely populated area and central location of the potential wind turbine sites. TheMassachusetts Department of Environmental Protection (DEP) regulates noise emissionsas a form of air pollution [Mass DEP, 1999]. Any new broadband sound source is limited

to raising overall noise levels no more than 10 dB(A) over the ambient baseline soundlevel. The ambient baseline is defined as the sound level that is exceeded 90% of thetime.

A noise study performed previously in Marblehead at a residential location resulted in abackground noise level measurement of 32 dB(A), which is unusually low. Based onnon-linear effects of adding sound levels, sounds generated by a wind turbine cannot bemore than 9.5 dB(A) over baseline levels to meet the overall noise standard. Therefore,according to state regulations, the installed wind turbine cannot generate sound levels, asheard by the closest resident, exceeding 41.5 dB(A). These readings are measured at theproperty line or at any inhabited buildings located within the property. For the landfilland beach locations the distance to the nearest residence is 108 meters (354 feet) and 78

meters (256 feet), respectively. With the short distance to the closest residence a windturbine could pose a problem with state noise regulations. Additional acousticmeasurements are needed at the specific locations of concern to accurately assess thesound levels.

Avian Issues

Unless the turbine is sited along an avian flyway or a nesting area, this is typically not amajor concern. The tubular towers that are recommended will have less impact on birdpopulations than a lattice tower as the former lacks perching sites that might otherwiseattract birds.

RECOMMENDATIONS/ AREAS OF FURTHERINVESTIGATION

The wind turbine that produces the most electricity at the lowest cost is the GE 1.5 MWmachine on an 80-meter tower. If a smaller turbine is desired, the Vestas V47 660 kWmachine on a 65-meter tower is recommended. The landfill site would have less of avisual impact and may be preferable to the beach site. If there were interest in locating aturbine at the public beach site, additional wind and noise measurements would beneeded.

If the community decides to move forward with a wind project based on the findings inthe report, a number of predevelopment tasks remain to be completed. A more detailedanalysis of the sound levels at turbine operating conditions would be needed to verify thatany sound generated by a wind turbine would be within legal limits. A comprehensive

environmental impact report, which includes the impacts on the air, water, land, andwildlife in the area, would be required. A geotechnical study should also be performed.Depending on the scope of the project, RERL would assist in developing a request forbids from turbine manufacturers or direct the participant to a commercial developer.

The Marblehead Municipal Light Department would be leading the siting and permittingprocess. Since they are a municipal utility, a power purchase agreement would not needto be negotiated.



18/18

REFERENCES

Blanding, Michael. The Healthiest Towns,Boston Magazine, April 2003.

Devine, Mia and Brendan OConnor. Feasibility Study for Marblehead, MA,University of Massachusetts, Amherst, 2003.

Ellis, A.F., Rogers, A.L., Manwell, J.F., Thompson Island Power Plant Options Study,report to DOER, 1998-1999.

Greenpeace. Media Briefing Coal: A Dirty, Deadly Power Source for New England

Manwell, J., McGowan, J., and Rogers, A. Wind Energy Explained: Theory, Design andApplication, John Wiley & Sons, Ltd., 2002.

Manwell, J.F., McGowan, J., Ellis, A., Rogers, A. Wright, S. Wind Turbine Siting in anUrban Environment: The Hull, MA, 660 kW Turbine, presented for theAmerican Wind Energy Association at WindPower 2003.

Massachusetts Department of Environmental Protection, section 310 CMR 7.00 AirPollution Control, Commonwealth of Massachusetts Regulations, 1999.

Massachusetts Division of Energy Resources, Renewable Energy & DistributedGeneration Guidebook, April 2001.

Massachusetts Geographic Information System. Interactive Mapping Tools forMassachusetts, www.massgis.com, 2001.

National Wind Coordinating Committee, Permitting of Wind Energy Facilities: AHandbook, March 1998.http://www.nationalwind.org/pubs/permit/permitting.htm

ReSoft, Ltd. WindFarm, Wind farm analysis, design and optimization software.

http://www.resoft.co.uk

TrueWind Solutions. Wind Resource Map of Southern New England,www.truewind.com

University of Massachusetts Wind Energy Engineering Minicodes, version 1.0.http://www.ceere.org/rerl/rerl_availsoftware.html

Websites - Wind Turbine Manufacturers

Bonus www.bonus.dk

GE Wind Energy www.gepower.com/dhtml/wind/en_us/index.jsp

MADE www.made.es

NEG Micon http://www.neg-micon.dk

Nordex http://www.nordex-online.com

Vestas http://www.vestas.dk

AWEA 2003 Devine OConnor Ellis Rogers Wright Page 18
http://www.massgis.com/http://www.nationalwind.org/pubs/permit/permitting.htmhttp://www.resoft.co.uk/http://www.truewind.com/http://www.ceere.org/rerl/rerl_availsoftware.htmlhttp://www.bonus.dk/http://www.gepower.com/dhtml/wind/en_us/index.jsphttp://www.made.es/http://www.neg-micon.dk/http://www.nordex-online.com/http://www.vestas.dk/http://www.vestas.dk/http://www.nordex-online.com/http://www.neg-micon.dk/http://www.made.es/http://www.gepower.com/dhtml/wind/en_us/index.jsphttp://www.bonus.dk/http://www.ceere.org/rerl/rerl_availsoftware.htmlhttp://www.truewind.com/http://www.resoft.co.uk/http://www.nationalwind.org/pubs/permit/permitting.htmhttp://www.massgis.com/

Documents

WEPS and Marble Head Wind Feasibility AWEA03