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Dept of EE, DTU 1

PROPOSAL

On

“FUTURE HOUSE”

2013

DEPARTMENT OF ELECTRICAL ENGINEERING

DELHI TECHNOLOGICAL UNIVERSITY,

NEW DELHI.

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INTRODUCTION-

Number of Towns and Villages electrified in India by IIFL, it can be seen that even after

65 years of independence 17.7 percent of India is still in dark during nights. All of the

5161 towns in India are electrified, i.e. cent percent in the case of towns. However, in

India villages are more than towns and development of India is only possible by the

development of those villages. Out of 593732 villages in India only 488439 villages are

electrified, i.e. 105293 villages are un-electrified. Andhra Pradesh, Goa, Kerala, Punjab,

Tamil Nadu, Haryana, and Delhi are the few of the states that are 100% electrified.

Arunachal Pradesh, Bihar, Jharkhand, Orissa, Meghalaya,and Tripura are the states where

less than 60% of the villages are electrified. The worst situation is in Jharkhand

where only 31.1 %villages are electrified. The consumption of electricity in the country is

increasing at the rate of 10% per year. The energy usage has been increasing through

years, but there has been no sufficient increase in the production. In the case of

electricity, this leads to load shedding and increase in prices.

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FIG1-: FLOOR PLAN OF THE HOUSE

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PHOTVOLTAIC SYSTEM DESIGN AND INSTALLATION

Photovoltaic (pv) power systems convert sunlight directly into electricity. A residential

pv power system enables a homeowner to generate some or all of their daily electrical

energy demand on their own roof, exchanging daytime excess power for future energy

needs (i.e. Nighttime usage). The house remains connected to the electric utility at all

times, so any power needed above what the solar system can produce is simply drawn

from the utility. Pv systems can also include battery backup or uninterruptible power

supply (ups) capability to operate selected circuits in the residence for hours or days

during a utility outage.

BASIC PRINCIPLES TO FOLLOW WHEN DESIGNING A

QUALITY PV SYSTEM

1. Select a packaged system that meets the owner's needs. Customer criteria for a system

may include reduction in monthly electricity bill, environmental benefits, desire for

backup power, initial budget constraints, etc. Size and orient the pv array to provide the

expected electrical power and energy.

2. Ensure the roof area or other installation site is capable of handling the desired system

size.

3. Specify sunlight and weather resistant materials for all outdoor equipment.

4. Locate the array to minimize shading from foliage, vent pipes, and adjacent structures.

5. Design the system in compliance with all applicable building and electrical codes.

6. Design the system with a minimum of electrical losses due to wiring, fuses, switches,

and inverters.

7. Properly house and manage the battery system, should batteries be required.

8. Ensure the design meets local utility interconnection requirements.

TYPICAL SYSTEM DESIGNS AND OPTIONS

Pv Electrical System Types

There are two general types of electrical designs for pv power systems for homes

Systems that interact with the utility power grid and have no battery backup capability.

Systems that interact and include battery backup as well.

Grid-Interactive Only (No Battery Backup) This type of system only operates when the utility is available. Since utility outages are

rare, this system will normally provide the greatest amount of bill savings to the customer

per dollar of investment. However, in the event of an outage, the system is designed to

shut down until utility power is restored.

TYPICAL SYSTEM COMPONENTS: Pv array: A pv array is made up of pv modules, which are environmentally-sealed

collections of pv cells—the devices that convert sunlight to electricity. The most common

pv module that is 5-to-25 square feet in size and weighs about 3-4 lbs./ft2. Often sets of

four or more smaller modules are framed or attached together by struts in what is called a

panel. This panel is typically around 20-35 square feet in area for ease of handling on a

roof. This allows some assembly and wiring functions to be done on the ground if called

for by the installation instructions.

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Balance Of System Equipment (Bos): BOS includes mounting systems and wiring

systems used to integrate the solar modules into the structural and electrical systems of

the home. The wiring systems include disconnects for the dc and ac sides of the inverter,

ground-fault protection, and overcurrent protection for the solar modules. Most systems

include a combiner board of some kind since most modules require fusing for each

module source circuit. Some inverters include this fusing and combining function within

the inverter enclosure.

Dc-Ac Inverter: This is the device that takes the dc power from the pv array and

converts it into standard ac power used by the house appliances. Metering: this includes

meters to provide indication of system performance. Some meters can indicate home

energy usage.

Other Components: utility switch (depending on local utility)

FIG2: Grid Interactive Pv System Without Battery Backup

MOUNTING OPTIONS There are several ways to install a pv array at a residence. Most pv systems produce 5-to-

10 watts per square foot of array area. This is based on a variety of different technologies

and the varying efficiency of different pv products. A typical 2-kw pv system will need

200-400 square feet of unobstructed area to site the system. Consideration should also be

given for access to the system. This access space can add up to 20% of needed area to the

mounting area required.

Roof Mount Often the most convenient and appropriate place to put the pv array is on the roof of the

building. The pv array may be mounted above and parallel to the roof surface with a

standoff of several inches for cooling purposes. Sometimes, such as with flat roofs, a

separate structure with a more optimal tilt angle is mounted on the roof. Proper roof

mounting can be labor intensive. Particular attention must be paid to the roof structure

and the weather sealing of roof penetrations. It is typical to have one support bracket for

every 100 watts of pv modules. For new construction, support brackets are usually

mounted after the roof decking is applied and before the roofing materials is installed.

The crew in charge of laying out the array mounting system normally installs the

brackets. The roofing contractor can then flash around the brackets as they install the

roof. A simple installation detail and a sample of the support bracket is often all that is

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needed for a roofing contractor to estimate the flashing cost. Masonry roofs are often

structurally designed near the limit of their weight-bearing capacity. In this case, the roof

structure must either be enhanced to handle the additional weight of the pv system or the

masonry roof transitioned to composition shingles in the area where the pv array is to be

mounted. By transitioning to a lighter roofing product, there is no need to reinforce the

roof structure since the combined weight of composite shingles and pv array is usually

less than the displaced masonry product.

Shade Structure An alternative to roof mounting is to mount the system as a shade structure. A shade

structure may be a patio cover or deck shade trellis where the pv array becomes the

shade. These shade systems can support small to large pv systems. The construction cost

with a pv system is a little different

Than for a standard patio cover, especially if the pv array is acts as part or the entire

shade roof. If the pv array is mounted at a steeper angle than a typical shade structure,

additional structural enhancements may be necessary to handle the a dditional wind

loads. The weight of the pv array is 3-to-5 lbs./ft2, which is well within structural limits

of most shade support structures. The avoided cost of installing roof brackets and the

associated labor could be counted toward the cost of a fully constructed patio cover. The

overall cost of this option will likely be higher than roof mounting, but the value of the

shade often offsets the additional costs.

Other issues to consider include :

• Simplified array access for maintenance

• Module wiring, if visible from underneath, must be carefully concealed to keep the

installation aesthetically pleasing.

• Cannot grow vines, or must be diligent about keeping it trimmed back from modules

and wiring.

ESTIMATING SYSTEM OUTPUT Pv systems produce power in proportion to the intensity of sunlight striking the solar

array surface. The intensity of light on a surface varies throughout a day, as well as day to

day, so the actual output of a solar power system can vary substantial. There are other

factors that affect the output of a solar power system. These factors need to be understood

so that the customer has realistic expectations of overall system output and economic

benefits under variable weather conditions over time.

FACTORS AFFECTING OUTPUT STANDARD TEST CONDITIONS Solar modules produce dc electricity. The dc output of solar modules is rated by

manufacturers under standard test conditions (stc). These conditions are easily recreated

in a factory, and allow for consistent comparisons of products, but need to be modified to

estimate output under common outdoor operating conditions. Stc conditions are: solar

cell temperature = 25 oC; solar irradiance (intensity) = 1000 w/m2(often referred to as

peak sunlight intensity, comparable to clear summer noon time intensity); and solar

spectrum as filtered by passing through 1.5 thickness of atmosphere (astm standard

spectrum). A manufacturer may rate a particular solar module output at 100 watts of

power under stc, and call the product a “100-watt solar module.” This module will often

have a production tolerance of +/-5% of the rating, which means that the module can

produce 95 watts and still be called a “100-watt module.” To be conservative, it is best to

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use the low end of the power output spectrum as a starting point (95 watts for a 100-watt

module).

TEMPERATURE Module output power reduces as module temperature increases. When operating on a

roof, a solar module will heat up substantially, reaching inner temperatures of 50-75 oC.

For crystalline modules, a typical temperature reduction factor is 89% or 0.89. So the

“100-watt” module will typically operate at about 85 watts (95 watts x 0.89 = 85 watts) in

the middle of a spring or fall day, under full sunlight conditions.

DIRT AND DUST Dirt and dust can accumulate on the solar module surface, blocking some of the sunlight

and reducing output. Much of california has a rainy season and a dry season. Although

typical dirt and dust is cleaned off during every rainy season, it is more realistic to

estimate system output taking into account the reduction due to dust buildup in the dry

season. A typical annual dust reduction factor to use is 93% or 0.93. So the “100-Watt

module,” operating with some accumulated dust may operate on average at about 79

watts (85 watts x 0.93 = 79 watts).

MISMATCH AND WIRING LOSSES The maximum power output of the total pv array is always less than the sum of the

maximum output of the Individual modules. This difference is a result of slight

inconsistencies in performance from one module to the next and is called module

mismatch and amounts to at least a 2% loss in system power. Power is also lost to

resistance in the system wiring. These losses should be kept to a minimum but it is

difficult to keep These losses below 3% for the system. A reasonable reduction factor for

these losses is 95% or 0.95.

DC TO AC CONVERSION LOSSES The dc power generated by the solar module must be converted into common household

ac power using an inverter. Some power is lost in the conversion process, and there are

additional losses in the wires from the rooftop array down to the inverter and out to the

house panel. Modern inverters commonly used in residential pv power systems have peak

efficiencies of 92-94% indicated by their manufacturers, but these again are measured

under well-controlled factory conditions. Actual field conditions usually result in overall

dc-to-ac conversion efficiencies of about 88-92%, with 90% or 0.90 a reasonable

compromise. So the “100-watt module” output, reduced by production tolerance, heat,

dust, wiring, ac conversion, and other losses will translate into about 68 Watts of AC

power delivered to the house panel during the middle of a clear day (100 Watts x 0.95 x

0.89 x 0.93 x 0.95 x 0.90 = 67 Watts).

INSTALLATION LABOR EFFORT Installation effort is very sensitive to specific house layouts and roofing type. An

experienced crew can install a 2 kW non-battery PV system in two-to-four person-days.

Systems with large solar arrays are relatively less effort per watt of power and kWh of

energy than smaller systems because the installation of the inverter and other hardware

required by all PV systems is spread over more solar modules. Systems with battery

backup are more labor intensive than non-battery systems because of the additional

wiring required for wiring the critical load subpanel. A battery system can add 50-100%

to the time required for the installation.

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PROPOSED INCLINATION OF ROOFS Based on various calculations, we found that roof’s inclination should be kept at 20

degrees, for efficient utilisation of light. Based on that, the following model is proposed.

Isometric Projection of room

FIG 3 : ISOMETRIC PROJECTION OF ROOM

Side view of room

FIG 4 : SIDE VIEW OF ROOM

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LIGHTING SYSTEMS 1. Solar Tube Lighting

These devices channel sunlight from your rooftop through your attic space into an

overhead light that resembles a conventional light, can be used with the push of a

button, and requires no energy to run. A softening lens and high-quality reflective

materials allow for even lighting on sunny and cloudy days. Many solar tube

lights come equipped with a conventional back-up light for night time use.

Figure 5: Diagram of a Solar Tube [1]

Reference : []

2. Solar Tube with Mechanical Tracker

Another specialized system consists of a receiver which tracks the sun

mechanically and directs the sun light through cables for indoor lighting

purposes.[2]

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FIG 6: SOLAR TUBE WITH MECHANICAL TRACKING

3. LED Lighting

The next generation of efficient lighting brings LEDs or Light Emitting Diodes into the

picture. While the cost of production has kept the purchasing cost significantly high, the

benefits outweigh the pricing issues.

The standard unit for comparison is lumens which is the SI derived unit of luminous flux

which is the total amount of visible light emitted by source.

Benefits of LED Bulbs :

1. Long lasting: LED bulbs last up to 10 times as long as compact fluorescents, and

far longer than typical incandescent bulbs.

2. Durable: LEDs do not have a filament; they are not damaged under

circumstances when a regular incandescent bulb would be broken. Because they

are solid, LED bulbs hold up well to jarring and bumping.

3. Mercury Free: no mercury is used in the manufacturing of LEDs.

4. Cost effective: although LEDs are initially expensive, the cost is recouped over

time and in battery savings. LED bulb use was first adopted commercially, where

maintenance and replacement costs are expensive. But, the cost of new LED

bulbs has gone down considerably in the last few years and is continuing to go

down.

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The Following Table Depicts The Comparison In Lumens And Watts For Various

Lighting Sources:

LUMENS POWER RATING OF LED (in Watts)

POWER RATING OF INCANDASCENT BULB(in Watts)

POWER RATING OF CFL (in Watts)

450 4-5 40 9-13

800 6-8 60 13-15

1100 9-13 75 18-25

1600 16-20 100 23-30

Table: Comparison of Lumen to Watt values for various lighting sources [3]

While incandescent bulbs provide diffused light that spreads in all directions, LED

lighting is used more as directional lighting. These can be powered from the energy

stored from the PV array during the day.

Table : Cost Comparison Of Various Lighting Sources

Table : Cost Comparison of various lighting sources.

[4]

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The typical lighting setup is shown below:

Here the bold dots marked on the floor plan show the proposed location of the lighting

sources (solar tube + LED) combined:

FIG 7:THE TYPICAL LIGHTING SETUP

Lighting will be controlled intelligently. Sensors located on doorways will detect

movement of people in and out of the room. For instance, if the individual steps out of

the bedroom and into the kitchen, the lights of the bedroom will dim automatically and

shift to Power Saving Mode while lighting in the Kitchen will switch to Normal Mode.

Manual override switches shall be provided on the walls too.

During the day, lighting shall be provided using solar tubes which have adjustable covers

to control the intensity of light. As the day progresses, timed sensors shall track the

intensity of light falling in the solar tubes and hence control the artificial lighting

provided within with increasing darkness in the evening and night (or during cloudy

days).

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Figure 8: Control Algorithm for system controlling automatic lighting systems for

day and night

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PEDAL-POWER INTRODUCTION-: World is a storehouse of energy. We all know that energy can neither be created nor

destroyed but can be transformed from one form to another. But we are wasting resources

that can produce energy as if they are limitless. If we can renew and reuse the energy we

waste, it would help in some way to the problem of scarcity of energy, which is the major

threat of present world. Humans are able to generate approximately 150W of power while

riding bicycle. However, this power goes waste without any use. If we can make use of

this energy, we would be able to power many electronic devices. A dynamo or an

alternator can be used for harvesting the energy generated by a cycle rider while riding.

We can charge mobile phones or a small lighting device with this power. Not only in

bicycles but also in alternator bikes, cars, and exercise bikes we can use this principle.

In India, many of the villages are still without electricity and most of them use bicycle as

their medium of transportation. In such places, our system will be of great help. Charging

of the battery can be done by a layman by just connecting the circuit to the output of the

dynamo/alternator which is connected to the bicycle. This would charge the NiMH

batteries.

As long as we are pedalling and the system is working fine, we can get the power

whenever needed. Power generation using bicycle is very cheap and eco-friendly. Even

though people have been using pedal power for various day-to-day chores, generating

electricity from pedalling was not in vogue until few decades back. Today dynamo

equipped bicycles are common which power the incandescent headlights during night.

The rotational energy that is generated when the tire rotates because of the application of

force on the pedals can be used in two ways. This energy can also be used in

dynamo/alternator, which is then converted to electrical energy. Rotational energy of the

tire can be used to pump water out from the well, to drive a washing machine, to operate

blender/grinder etc.

DYNAMO: Bicycle Dynamos are alternators equipped with permanent magnets, which produce ac

current.

Two types of dynamos available are :-

The hub dynamo o Hub dynamo is built into the hub of a bicycle wheel. Here generation of

electricity is done by using the rotation of the bicycle wheel.

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FIG 9: HUB DYNAMO

The Bottle Dynamo:- o It is also a small electric generator like hub dynamo.It is generally

placed to the rear wheel of bicycle.

FIG 10: BOTTLE DYNAMO

ALTERNATOR:- The output energy from the dynamo is very low. Only three 1.2V NiMH batteries can be

charged using this power, which can be used for low power applications like small led

lights. Also, it takes a lot of time in charging these batteries. It is definite that the dynamo

output will be insufficient for high power applications and an alternative is needed.

A dynamo can be replaced with an alternator since it is capable of producing more power

in less time. Alternator has both pros and cons over dynamo, but alternator generates

more power than dynamo with lesser time and effort.

One way to connect an alternator with the bicycle is to place it behind the seat by

removing the carrier. The shaft of the alternator should be connected to the tire with a

belt that rolls over shaft on one end and other end rolls over a cylindrical structure

attached to its rear tire’s hub. In this way when the bicycle moves, the structure rotates

and thereby facilitates rotation of alternator’s shaft.

The other way to connect the alternator with the bicycle is by making the shaft directly

roll over the tire. A rubber cap placed on the shaft is used to provide grip and to facilitate

roll without slipping.

Among the two ways, the first way will be more power efficient but the bicycle is needed

to be pedalled in stationary mode.

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As alternator would produce more power, a rechargeable battery of high voltage rating is

required. The rectifier (conventional bridge rectifier) and filter will not undergo any

alterations. However, in the regulator part, a regulated voltage of 15v has to be

maintained using a regulator IC 7815.

CIRCUIT FOR POWER GENERATION

FIG 11:CIRCUIT FOR POWER GENERATION

COMPONENTS REQUIRED

A Bicycle

Type of bike:

Road bikes are most suitable type of bike for generating electricity because they have

slick tires. Slick tyres help keep friction and noise to a minimum level. Road bikes are

designed to be efficient on smooth roads. You will generally get more watts from a road

bike than a town (designed for comfort) or a mountain bike (designed for bumps and

bashes).

Gears:

Geared bikes have the advantage that cyclists of different abilities can use them.

Single speed bikes have the advantage that the cyclist cannot change gear and

make life easier for him/herself. Therefore you can almost guarantee the same

power out from each person.

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FIG 12: GROUP OF PEDAL GENERATORS

Batteries/Super capacitors Rechargeable battery is used to store the energy produced by pedaling. Rechargeable

batteries are made up of one or more electrochemical cell used to store energy in the form

of electrical energy. The only reason why batteries are preferred over capacitor is its easy

usage i.e. the batteries after recharging can be easily removed from the charging case and

can be used for desired purpose like for lighting up torch, etc.

A battery for use with a pedal power set up should not be too large. Industrial pocket

plate nickel cadmium batteries are ideal for this application because they have a relatively

flat discharge curve and don't mind being deeply discharged and operated in a partial

state of charge. This applies only to the pocket plate type of NiCad cell which has no

memory characteristic. Unless several people are contributing regularly to the charging

process, 20-40 ampere hours of capacity is very adequate. Larger capacities will work of

course, or you can simply pipe the current generated into the larger battery bank of a

complete home

power system.

Voltage Regulator The alternative to using a battery is to use a voltage regulator to buffer the variable output from the generator down to a constant 12.6 volts. With this arrangement, the lights and other appliances are on while you crank but go off when you quit. This offers a real education in the amount of power we drain from the system. Cranking a color TV and VCR is hard work while powering a reading light or two is so easy of a load that you hardly feel it. The advantage of having a regulator available is that you can get full use from the system even if your battery is flat dead. It also doesn't take up the space required by the batteries and it provides some discipline in the use of certain appliances. Some folks, for example, connect the TV set to their bike generator with a regulator and require the kids to carry their own weight when watching television.

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Belts and Stands The motor needs to be attached to your stand somehow and then tensioned up to the back

wheel of your bike. The location of the motor is critical and you may need to make a

number of mounting points suitable for different bicycles.

FIG 13: CYCLE STAND

FIG 14: BELT

An Inverter

If you are wishing to use AC mains powered appliances you will need to purchase an

inverter. There are 2 types of inverters. A pure sine wave inverter creates a smooth AC

output. A quasi sine makes a square wave. Some devices may not work with a quasi sine.

Inverters are designed to work with batteries so they usually work with voltages between

9 and 14volts.

APPLICATIONS OF PEDAL POWER Charging Mobile Phones For this we need a mobile charging circuit which would give the appropriate voltage and

current required for charging the mobile. Here, the difference will be the input to

charging circuit. In normal chargers, the input is from ac main 230V.However,in our case

the voltage will be of lower value.

Correspondingly, some changes are required to be made in the mobile charging circuit.

Here two types of chargers are possible:

The first, in which the mobile phone battery is charged by connecting the charger output to mobile phone directly.

The second in which battery of the mobile phone is charged separately.

Pedal Powered Laptops

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Laptops powered using solar energy is available, but not everyone can afford to buy it. A

simpler way will be to pedal and charge it. This already exists in Afghanistan and they

claim that even a third grader will be able to use it without any difficulty. Here the pedal

is fitted to the laptop table so that while using the laptop one could charge it.

FIG 15: LAPTOP CHARGING

Pedal Powered Washing Machine Pedal power can be used to operate washing machine. It agitates, cleans and rinses the

clothes. Already existing models uses pedal power in two different ways. In one of the

model, plastic barrel filled with water, soap powder and clothes are put and lid is closed.

This plastic barrel itself is rotated by pedalling. In the other model also plastic barrel is

used. But one person can sit on that barrel and pedal the foot pedal provided at the bottom

of the plastic barrel.

Blenders Drive coupling of the blender is connected to the bicycle tire, which would rotate the

blades of the blender. Electric blenders are high-powered devices, which work at about

500watts power. If blenders can be operated mechanically it would save electricity as

well as money.

FIG 16: BLENDER PEDAL POWER GENERATOR

ENERGY LOSSES

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Energy loss cannot be avoided and is present in each stage, from production to storage.

Energy loss happens in the battery, in the alternator/dynamo, in the converter (which

converts ac to dc), in the voltage regulator. This means that the total energy loss in a

pedal powered generator will be about 50-70 %. Losses can be minimized by reducing

the number of electrical connections and use mechanical connections wherever possible.

Considering the cost factor, components of maximum efficiency must be used.

COST SINGLE BIKE GENERATOR

S.NO COMPONENTS QUANTITY PRICE in INR

1 GEARED CYCLE 1 15000

2 STAND 1 2000

3 BELT 1 1000

4 GENERATOR (300 W) 1 5000

5 LEAD ACID BATTERY 1 10000

6 INVERTER 1 7000

TOTAL 40000

ADVANTAGES Pedal power vehicles are becoming popular day by day. Pollution in the

environment is causing serious health issue and doctors are emphasizing the use of bicycle as an exercise to be healthy. On this line Chinese are replacing their vehicles with pedal power vehicles.

At a time when there is energy crisis casting its shadow all over the world, one has to look into alternate renewable energy resources. One such alternate way to generate power is presented in this paper. The rotational energy of the tires in the bicycle, generated by pedalling can be used to operate small powered devices. Both dynamo and alternator can be used and various options and situations where a dynamo or alternator can be used are provided.

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PIEZOELECTRICITY:

Piezoelectricity is the electric charge that accumulates in certain solid materials (notably

crystals, certain ceramics, and biological matter such as bone, DNA and various proteins)

in response to applied mechanical stress. The word piezoelectricity means electricity

resulting from pressure. It is derived from the Greek word “piezo”, which means to

squeeze or press, and electric or electron, which stands for amber, an ancient source of

electric charge. Piezoelectricity was discovered in 1880 by French physicists Jacques and

Pierre Curie. They found that when certain types of crystals such as quartz, tourmaline,

and Rochelle salt, are compressed along certain axes, the resulting mechanical

deformation produces a voltage on the surface of the crystal. When pressure is applied to

an object, a negative charge is produced on the expanded side and a positive charge on

the compressed side. Once the pressure is relieved, electrical current flows across .This

effect is known as piezoelectric effect. The converse effect is also possible i.e. when the

emf applied along certain electrical axes in the crystal ,this crystal produces mechanical

vibrations .This effect is used in some variety of practical devices such as buzzers, ultra

sonic filters and sonar for the production of Ultrasonic waves.

FIG 17: ELECTROMECHANICAL CONVERSION VIA PIEZOELECTRICITY

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FIG 18: PIEZOELECTRIC CRYSTALS

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Advantages of Piezoelectricity:

The rise of piezoelectric technology is directly related to a set of inherent advantages.

The high modulus of elasticity of many piezoelectric materials is comparable to that of

many metals and goes up to 106 N/m². Even though piezoelectric sensors are

electromechanical systems that react to compression, the sensing elements show almost

zero deflection. This is the reason why piezoelectric sensors are so rugged, have an

extremely high natural frequency and an excellent linearity over a wide amplitude range.

Additionally, piezoelectric technology is insensitive to electromagnetic fields and

radiation, enabling measurements under harsh conditions. Some materials used

(especially gallium phosphate or tourmaline) have an extreme stability even at high

temperature, enabling sensors to have a working range of up to 1000 °C. Tourmaline

shows pyroelectricity in addition to the piezoelectric effect; this is the ability to generate

an electrical signal when the temperature of the crystal changes.

APPLICATIONS:

It has been found that piezoelectric crystals that have been embedded in the sole of a shoe

can yield a small amount of energy with each step. This could be applied in a way that

the power for instruments such as torches, cell phones or other entertainment devices can

be sourced from the movement of the operator.

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Block Diagram of Footstep Power Generation:

FIG 19: BLOCK DIAGRAM OF FOOT STEP PEWER GENERATION

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FIG 20: PIEZOSHOES

FIG 21: GRAPH OF PIEZOELECTRICITY PRODUCED

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Piezoelectric Generators: Piezoelectric generator is nothing but a piezoelectric crystal sandwiched between two

metallic electrodes. So when the mechanical pressure/stress is applied on the crystal, emf

is generated.

FIGURE 22: PIEZO GENERATOR

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WINDOWS The use of heat reflecting glass in place of ordinary glass increases energy efficiency of

the house by a considerable amount. Heat-reflecting windows are usually sealed, double-

glazed units—ones with two panes of glass separated by a noble (non-reactive) gas such

as argon that improves insulation (stops heat from escaping in air drafts). The inner

surface of one of the panes of glass is coated with a very thin layer of metal or metallic

oxide (typical coatings include titanium dioxide, bronze, silver, or stainless steel). Heat

reflecting glass lets visible light pass through it virtually unimpeded, but the metallic

coating reflects short wavelength ultraviolet light very effectively, much like a mirror.

So, sunlight enters the home as normal, but the heat is reflected back again. Even when

the sun has moved around and is not shining directly, objects warmed by ultraviolet

radiation from the sun can still re-radiate infrared radiation into the home. But heat

reflecting glass will simply reflect it back.

FIG 23: WINDOW HEAT REFLECTION

During the night time (especially useful during winters, heat-reflecting glass, the metallic

coating will reflect most of the infra red radiation straight back into the room.[5]

Spacious windows using heat reflecting glass shall be provided that will maximize light

entering the house during the daytime. The house will require minimum air conditioning

as the glass will keep most of the heat out of the house. This reduces the power

consumption of the house dramatically.

SELECTION

When selecting windows for energy efficiency, it's important to first consider

their energy performance ratings in relation to your climate and your home's design. This

will help narrow your selection.

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FIG 24 WINDOW DESIGN

A window's energy efficiency is dependent upon all of its components. Window

frames conduct heat, contributing to a window's overall energy efficiency, particularly

its U-factor. Glazing or glass technologies have become very sophisticated, and designers

often specify different types of glazing or glass for different windows, based on

orientation, climate, building design, etc.

Another important consideration is how the windows operate, because some operating

types have lower air leakage rates than others, whichwill improve your home's energy

efficiency. Traditional operating types include:

Awning. Hinged at the top and open outward. Because the sash closes by pressing

against the frame, they generally have lower air leakage rates than sliding windows.

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Casement. Hinged at the sides. Like awning windows, they generally have lower

air leakage rates than sliding windows because the sash closes by pressing against

the frame.

Fixed. Fixed panes that don't open. When installed properly they're airtight, but

are not suitable in places where window ventilation is desired.

Hopper. Hinged at the bottom and open inward. Like both awning and casement,

they generally have lower air leakage rates because the sash closes by pressing

against the frame.

Single- and double-hung. Both sashes slide vertically in a double-hung window.

Only the bottom sash slides upward in a single-hung window. These sliding windows

generally have higher air leakage rates than projecting or hinged windows.

Single- and double-sliding. Both sashes slide horizontally in a double-sliding window.

Only one sash slides in a single-sliding window. Like single- and double-hung windows,

they generally have higher air leakage rates than projecting or hinged windows

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FIGURE 25- WINDOW TYPES

INSTALLATION

Even the most energy-efficient window must be properly installed to ensure energy

efficiency. Therefore, it's best to have a professional install your windows.

Window installation varies depending on the type of window, the construction of the

house (wood, masonry, etc.), the exterior cladding (wood siding, stucco, brick, etc.), and

the type (if any) of weather-restrictive barrier.

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Windows should be installed according to the manufacturer’s recommendations and be

properly air sealed during installation to perform correctly. To air seal the

window, caulk the frame and weatherstrip the operable components.

TYPES OF WINDOW FRAMES

Improving the thermal resistance of the frame can contribute to a window's overall

energy efficiency, particularly its U-factor. There are advantages and disadvantages to all

types of frame materials, but vinyl, wood, fiberglass, and some composite frame

materials provide greater thermal resistance than metal.

ALUMINUM OR METAL FRAMES

Although very strong, light, and almost maintenance free, metal or aluminum window

frames conduct heat very rapidly, which makes metal a very poor insulating material. To

reduce heat flow and the U-factor, metal frames should have a thermal break -- an

insulating plastic strip placed between the inside and outside of the frame and sash.

COMPOSITE FRAMES

Composite window frames consist of composite wood products, such as particleboard

and laminated strand lumber. These composites are very stable, they have the same or

better structural and thermal properties as conventional wood, and they have better

moisture and decay resistance.

FIBERGLASS FRAMES

Fiberglass window frames are dimensionally stable and have air cavities that can be filled

with insulation, giving them superior thermal performance compared to wood or

uninsulated vinyl.

VINYL FRAMES

Vinyl window frames are usually made of polyvinyl chloride (PVC) with ultraviolet light

(UV) stabilizers to keep sunlight from breaking down the material. Vinyl window frames

do not require painting and have good moisture resistance. The hollow cavities of vinyl

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frames can be filled with insulation, which makes them thermally superior to standard

vinyl and wood frames.

WOOD FRAMES

Wood window frames insulate relatively well, but they also expand and contract in

response to weather conditions. Wood frames also require regular maintenance, although

aluminum or vinyl cladding reduces maintenance requirements.

TYPES OF WINDOW GLAZING OR GLASS

In addition to choosing a frame type, you will need to consider what type of glazing or

glass you should use to improve your home's energy efficiency. Based on

various window design factorssuch as window orientation, climate, building design, etc.,

you may even want to choose different types of glazing for different windows throughout

your home.

GAS FILLS

To improve the thermal performance of windows with insulated glazing, some

manufacturers fill the space between the panes with inert gas -- commonly argon or

krypton -- that has a higher resistance to heat flow than air.

HEAT-ABSORBING TINTS

Heat-absorbing window glazing contains special tints that change the color of the glass.

Tinted glass absorbs a large fraction of the incoming solar radiation through a window,

reducing the solar heat gain coefficient (SHGC), visible transmittance (VT), and glare.

Some heat, however, continues to pass through tinted windows by conduction and re-

radiation, so the tint doesn't lower a window's U-factor. Inner layers of clear glass or

spectrally selective coatings can be applied on insulated glazing to help reduce these

types of heat transfer.

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The most common gray- and bronze-tinted windows are not spectrally selective, and

reduce the penetration of both light and heat. Blue- and green-tinted windows offer

greater penetration of visible light and slightly reduced heat transfer compared with other

colors of tinted glass. In hot climates, black-tinted glass should be avoided because it

absorbs more light than heat. Tinted, heat-absorbing glass reflects only a small

percentage of light, so it does not have the mirror-like appearance of reflective glass.

Note that when windows transmit less than 70% of visible light, indoor plants can die or

grow more slowly.

INSULATED

Insulated window glazing refers to windows with two or more panes of glass. To insulate

the window, the glass panes are spaced apart and hermetically sealed, leaving an

insulating air space. Insulated window glazing primarily lowers the U-factor, but it also

lowers the SHGC.

LOW-EMISSIVITY COATINGS

Low-emissivity (low-e) coatings on glazing or glass control heat transfer through

windows with insulated glazing. Windows manufactured with low-e coatings typically

cost about 10% to 15% more than regular windows, but they reduce energy loss by as

much as 30% to 50%.

A low-e coating is a microscopically thin, virtually invisible, metal or metallic oxide

layer deposited directly on the surface of one or more of the panes of glass. The low-e

coating lowers the U-factor of the window, and different types of low-e coatings have

been designed to allow for high solar gain, moderate solar gain, or low solar gain. A low-

e coating can also reduce a window's VT unless you use one that's spectrally selective.

Although low-e coatings are usually applied during manufacturing, some are available for

do-it-yourselfers. These films are inexpensive

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compared to total window replacements, last 10 to 15 years without peeling, save energy,

reduce fabric fading, and increase comfort.

REFLECTIVE COATINGS

Reflective coatings on window glazing or glass reduce the transmission of solar radiation,

blocking more light than heat. Therefore, they greatly reduce a window's VT and glare,

but they also reduce a window's SHGC. Reflective coatings usually consist of thin,

metallic layers, and come in a variety of colors, including silver, gold, and bronze.

Reflective window glazing is commonly used in hot climates to control solar heat gain.

The reduced cooling energy demands can be offset by the need for additional electrical

lighting, so reflective glass is used mostly for special applications.

SPECTRALLY SELECTIVE COATINGS

A special type of low-e coating is spectrally selective, filtering out 40% to 70% of the

heat normally transmitted through insulated window glass or glazing while allowing the

full amount of light transmission. Spectrally selective coatings are optically designed to

reflect particular wavelengths, but remain transparent to others. Such coatings are

commonly used to reflect the infrared (heat) portion of the solar spectrum while

admitting more visible light. They help create a window with a low U-factor and SHGC

but a high VT.

Spectrally selective coatings can be applied on various types of tinted glass to produce

"customized" glazing systems capable of either increasing or decreasing solar gains

according to the aesthetic and climatic effects desired. Computer simulations have shown

that advanced window glazing with spectrally selective coatings can reduce the electric

space cooling requirements of new homes in hot climates by more than 40%.

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Figure26: Floor plan showing spacious windows located so as to maximize light

input during the day.

To maximize light entering, care must be taken to align the windows (during

construction) in a East to West direction so as to maximize light input during the day.