1

Alexandria University

Faculty of Engineering

Electrical Power & Machines

4th Year

[Final Project]

Report #01

Project members:-

Ahmed Khalil Kareem Hameed

Amr Mamdoh Mansy Mohamed Ashraf Mohamed

Ali Mohamed Ali Mohamed Ismail Kamel

Ahmed Adel El-Gendy Mohamed Ismail Mohamed

Omar Magdy Mohamed Osama

2

Main Points Solar Energy ....................................................................................................................... 4

Solar Thermal Energy .................................................................................................... 4

Solar Thermal Application: ....................................................................................... 5

Solar Photovoltaic Systems ........................................................................................... 5

Types of PV systems .................................................................................................. 6

Components of PV System ........................................................................................ 6

Wind Energy ....................................................................................................................... 8

Types of Wind Turbines ................................................................................................ 8

HAWT ........................................................................................................................ 8

VAWT ........................................................................................................................ 9

Types of Generators ....................................................................................................... 9

Home Automation ............................................................................................................ 12

General Components: ................................................................................................... 12

Peripherals: ................................................................................................................... 13

Door Locks ............................................................................................................... 13

Light Control ............................................................................................................ 13

Security & Alarm ..................................................................................................... 13

Temperature/Climate Control.................................................................................. 14

Automatic Shading ................................................................................................... 14

Home Entertainment ................................................................................................ 14

Model ............................................................................................................................ 15

Wireless Transmission ..................................................................................................... 17

Types of WPT ............................................................................................................... 17

Near Field Transmission .......................................................................................... 17

Types of Near Field Transmission .......................................................................... 18

Far Field Transmission ............................................................................................ 20

Types of Far Field Transmission............................................................................. 20

Smart Materials................................................................................................................. 21

Cavity and solid walls .................................................................................................. 21

Solid wall insulation ..................................................................................................... 22

Roof Insulation: ............................................................................................................ 23

Energy Efficient Windows: ......................................................................................... 23

3

How energy-efficient glazing works ....................................................................... 23

Windows Frame materials ....................................................................................... 23

Windows U-values ................................................................................................... 24

Benefits of energy-efficient windows ..................................................................... 24

Energy-efficient doors.................................................................................................. 24

Energy Efficiency Rating of Air Conditioners ........................................................... 25

Energy Efficient Lightning: ......................................................................................... 26

References: ........................................................................................................................ 27

4

Solar Energy

Solar energy Originates with the thermonuclear fusion reactions occurring in the sun,

Represents the entire electromagnetic radiation (visible light, infrared, ultraviolet, x-

rays, and radio waves), This energy consists of radiant light and heat energy from the

sun, Out of all energy emitted by sun only a small fraction of energy is absorbed by

the earth., Just this tiny fraction of the sun’s energy is enough to meet all our power

needs.

The fossil fuels are nonrenewable sources so we cannot depend on them forever,

Though nuclear energy is a clean and green energy, as said by Dr.A.P.J Abdul Kalam,

there are always some problems associated with it, So the only option we have is solar

energy because it is a nonpolluting and silent source of electricity and also low

maintenance and long lasting energy.

How solar energy is used:-

- Solar Thermal Energy

- Solar Heating

- Solar Water Heating

- Solar Space Heating

- Solar Space Cooling

- Electricity Generation Using Solar Concentrators

- Photovoltaic Cells

Solar Thermal Energy

Solar thermal energy (STE) is a form of energy and a technology for harnessing solar

energy to generate thermal energy or electrical energy for use in industry, and in the

residential and commercial sectors.

Different techniques of active solar heating

and solar thermal power generation are

technically feasible and cost effective, and

some commercially available plants can

produce up to 350MW these systems are

highly dependent on the local climate and

energy needs; this is a big limitation because

only in certain regions these systems can be

efficient enough to be implemented.

5

Solar Thermal Application:

Water heating

A solar domestic hot water system uses the sun’s energy collected by a flat-plate solar

collector and transfers the heat to water or another liquid flowing through tubes. The

system then draws upon this reservoir when you need hot water inside your home.

Space heating

A solar space heater collects the sun’s energy by a solar collector and directs the

energy into a “thermal mass” for storage later when the space is the coldest. A thermal

mass can be a masonry wall, floor or any storage drum used specifically to absorb and

store the energy.

Solar Photovoltaic Systems

Photovoltaic (PV) is the name of a method of converting solar energy into direct

current electricity using semiconducting materials that exhibit the photovoltaic effect.

Photovoltaic are best known as a method for generating electric power by using solar

cells to convert energy from the sun into a flow of electrons. The photovoltaic effect

refers to photons of light exciting electrons into a higher state of energy, allowing

them to act as charge carriers for an electric current.

Solar photovoltaic are used in a number of ways, primarily to power homes that are

inter-tied or interconnected with the grid.

6

Types of PV systems

Stand-alone systems

Stand-alone systems, which are also called off-grid PV systems, rely on solar power

only.

These systems can consist of the PV modules and a load only or they can include

batteries for energy storage.

Grid-connected systems

Grid-connected PV systems have become increasingly popular for applications in the

built environment.

They are connected to the grid via inverters, which convert the DC power into AC

electricity. In small systems as they are installed in residential homes, the inverter is

connected to the distribution board, from where the PV-generated power is transferred

into the electricity grid or to AC appliances in the house.

Hybrid systems

Hybrid systems combine PV modules with a complementary method of electricity

generation such as a diesel, gas or wind generator.

In order to optimize the different methods of electricity generation, hybrid systems

typically require more sophisticated controls than stand-alone or grid-connected PV

systems.

Components of PV System

- A mounting structure in order to fix the modules and to direct them towards

the sun.

- Energy storage as a vital part of stand-alone systems, because it assures that

the system can deliver electricity during the night and in periods of bad

weather. Usually, batteries are used as energy-storage units.

- DC-DC converters in order to convert the module output, which will have a

variable voltage depending on the time of the day and weather conditions, to a

compatible output voltage that can be used as input for an inverter in a grid-

connected system.

- Inverters that are used in grid-connected systems to convert the DC electricity

originating from the PV modules into AC electricity that can be fed into the

electricity grid. Many inverters have a DC-DC converter included to convert

the variable voltage of the PV array to a constant voltage that is the input for

the actual DC-AC converter. Also stand-alone systems may have an inverter

7

that is connected to the batteries. The design of such an inverter differs

considerably from that for a grid-connected system.

- Charge controllers that are used in stand-alone systems to control charging and

often also discharging of the battery. They prevent the batteries from being

overcharged and also from being discharged via the PV array during night.

High-end charge controllers also contain DC-DC converters together with a

maximum power point tracker in order to make the PV voltage and current

independent from the battery voltage and current.

- Cables that are used to connect the different components of the PV system

with each other and to the electrical load. It is important to choose cables of

sufficient thickness in order to minimize resistive losses.

8

Wind Energy

Wind energy is one of the most important and promising sources of renewable energy

all over the world, mainly because it is considered to be nonpolluting and

economically viable. At the same time, there has been a rapid development of related

wind turbine technology.

Wind energy is basically

changing kinetic energy of the

wind into rotational energy. The

electrical generator then converts

this rotational energy into

electrical energy.

Wind Power depends on:

- Amount of air (volume)

- Speed of air (velocity)

- Mass of air (density)

Types of Wind Turbines

Wind turbines can be divided into two main types, horizontal axis wind turbines

(HAWT) and vertical axis wind turbines (VAWT) based on which direction they spin

either horizontally or vertically

HAWT

- It has a similar design to the wind mill

- It has blades that look like a propeller that spin on the horizontal axis.

- The main rotor shaft and electrical generator at the top of a tower, and they

must be pointed into the wind.

9

- The turbines are pointed to the wind using simple wind vane; placed with the

rotor for small turbines or using a wind sensor coupled with a servo motor for

large ones. In case of large turbines a gear box is used to turn the slow rotation

of the rotor into a faster rotation that suitable for driving an electrical

generator.

VAWT

- The main rotor shaft arranged vertically.

- With a vertical axis, the generator and other primary components can be

placed near the ground, so the tower does not need to support it, also makes

maintenance easier.

Points HAWTs VAWTs

Source of producing

electricity Large Large

Use of electrical

generator Yes Yes

Fanatical feasibility High Low

Operating speed From 3mph to 50mph From 1mph to 20mph

Range of power

production From 1kw to 6 Megawatts Less than 50 kw

Maintenance Relatively hard Easy

Size Commercial Non-commercial (small

applications)

Positioning Must face the wind don't need to face wind

Types of Generators

Synchronous or asynchronous generators are connected to the wind turbine through

gear box in case of asynchronous generators, or without gear box in case of

synchronous generators.

10

Synchronous generator Asynchronous (induction) generator

1- Wound rotor generator (WRSG) 1-Squirrel cage induction generator (SCIG)

2- Permanent magnet generator (PMSG) 2- Wound rotor induction generator (WRIG) A-Opti-Slip induction generator (OSIG) B- Doubly-fed induction generator (DFIG)

There are four different types of connection depending on the type of the generator.

Type A used only in fixed wind speed. Type B, C, and D mostly used because it

works at variable speed.

Currently, mainly, three wind turbine concepts dominate the market:

11

- Fixed-speed wind turbines with an induction generator directly connected to

the grid.

- Gearless wind turbines with a power electronic converter connected between

the stator and the grid.

- DFIG, i.e., a slip-ringed wound-rotor induction generator, where a power

electronic converter is connected between the rotor circuit and the grid.

The latter is currently the most popular one, due to its high energy efficiency and

due to the fact that a power electronic converter with a rating of only 20%–30% of

the rated wind turbine power is needed. However, it is the most difficult one to

control and also to model.

Points Induction Synchronous

SCIG WRIG OSIG DFIG WRSG PMSG

Excitation Not self excited

Not self excited

Not self excited

Can be self excited

Self excited Self excited

Price Cheap Expensive related to

SCIG Cheap Cheap Expensive Expensive

Mechanical

design

Simple and robust

Simple but not robust

Simple and robust

Simple and robust

Complicated Complicated

Use of gear

box

Must use gearbox

Must use gearbox

Must use gearbox

Must use gearbox

Gear box is not essential

Gear box is not essential

Speed range

operation Restricted Restricted

Wide but restricted

0-10% Wide Restricted Restricted

Efficiency Moderate High Moderate High Moderate High

12

Home Automation

It is the automatic and electronic control of household features, activity and

appliances.

Domestic activities can then be regulated with the touch of a button. From any remote

location, users can adjust the controls on home entertainment systems, limit the

amount of sunlight given to houseplants, or change the temperatures in certain rooms.

Home automation software is often connected through computer networks so that

users can adjust settings on their personal devices.

A good HA system is the one:

- Easy to use.

- Promote energy efficiency.

- Improves Safety of your home.

General Components:

Devices

Control

Peripherals

-Modern Access through hand-held devices as Mobiles and Tablets - With trigger events and Alerts

- Control unit that send the signals through to the peripherals such as lights, AC, home entertainment…etc

- Through wifi or TCP/IP

- Establishing a good control system to accept different types of peripherals: door locks, dimmers, thermostats…etc

13

Peripherals:

Door Locks

- Virtual keys to your home.

- Different keys with different

permissions

- Connected with the Alarm & Security

systems.

(Improves safety of your home)

Light Control

- Motion sensors detect a presence in a room and (switch/control) the light

accordingly.

- Dimmers automatically adjust LED brightness depending on the light level

(Promotes energy efficiency)

Security & Alarm

- Motion sensors & cameras.

- Activate alarms, call of law enforcement if

needed and send alert messages through

service controller to the home owner.

(Improves safety of your home)

14

Temperature/Climate Control

- Programmable thermostat ensures climate control

in the house by controlling AC/Heater temperature.

(Promotes energy efficiency)

Automatic Shading

- Control over blinds and curtains through the day.

- Keep rooms from getting hotter during the day; thus decreasing the use of

the AC or fans.

- It can be integrated with temperature control for AC and security system to

expose intruders.

- Morning wake ups integration with clock and alarm.

Home Entertainment

- One touch control over: TV, speaker, projector, streaming service

- Access all your movies, TV shows, music, books

- Connected with lighting system to control different modes

- Connected with Security and Alert system to view Cameras inside and

outside the house.

15

Model

We can design smart house system on small

scale using simple components like:

- Microcontroller : Arduino – Raspberry Pi

- Sensors : Ultrasonic – Infra Red – LDR

- LEDs – Lamps

- Motors

- LCDs

- Wireless modules

Door Lock

We can use:

- keypad

- MCU with predefined password

- LCD

- Buzzer

Designed system to accept the right password or

activate the alert system.

Using the keypad or input from a mobile or tablet

connected over WiFi

16

Light Control

We can use:

- Ultrasonic sensors for motion detection

- LDR sensor for light level in a room

- LEDs or Lamps to be controlled by MCU

Automatic Shading

We can use:

- LDR sensor for light level

outside

- Stepper Motor to control

motion of the curtain

- MCU to control the logic of

the circuit plus to allow

manual over-ride.

We can add different peripherals circuit to the system such as:

- Temperature control to send signal to AC or Heaters and display it on a

screen.

- We can track power consumption in the house.

- Smoke detection for fire-fighting system.

- …

We can design a mobile application to control the system over WiFi.

We can try to make a real life model over a limited location like a room; to control

220V appliances using the same MCU any system logic with relays and protection

circuit.

17

Wireless Transmission

The first visions of wireless power transmission came from Nikola Tesla in the early

20th century. His biggest project involved the Wardenclyffe Tower. Although the

transmitting tower could be used for wireless communications, it was constructed

with the intention to transmit wireless power.

In 2007, a group of researchers at MIT achieved wireless power transfer, powering a

light bulb of 60W over distances exceeding 2 meters with efficiency of around 40%.

In their wireless power system, they use a pair of strongly magnetically coupled

resonators, with a transmitter and a receiver forming a resonant pair.

Types of WPT

Near Field Transmission

Near-field or non-radiative region – This

means the area within about 1 wavelength (λ)

of the antenna. In this region the oscillating

electric and magnetic fields are separate and

power can be transferred via electric fields by

capacitive coupling (electrostatic induction)

between metal electrodes or via magnetic

fields by inductive coupling (electromagnetic

induction) between coils of wire.

18

It could drastically reduce the 6 billion batteries disposed of each year, a large source

of toxic waste and groundwater contamination.

It can be used to transform appliance into

cordless appliance.

It can be used in wit environment like

electric toothbrushes and electric razors to

reduce the hazard of electric shock.

Types of Near Field Transmission

Inductive Coupling

- Power is transferred between coils of wire by a magnetic field.

- The transmitter and receiver coils together form a transformer. An alternating

current (AC) through the transmitter coil creates an oscillating magnetic field

- The magnetic field passes through the receiving coil, where it induces an

alternating EMF (voltage) by Faraday's law of

induction, which creates an AC current in the

receiver.

- The induced alternating current may either

drive the load directly, or be rectified to direct

current (DC) by a rectifier in the receiver,

which drives the load.

inductive coupling can only achieve high efficiency

when the coils are very close together, usually

adjacent. In most modern inductive systems resonant inductive coupling is used, in

which the efficiency is increased by using resonant circuits. This can achieve high

efficiencies at greater distances than non-

resonant inductive coupling.

Resonant Inductive Coupling

- It is a form of inductive coupling in

which power is transferred by magnetic

fields between two resonant circuits

(tuned circuits), one in the transmitter and one in the receiver.

- Each resonant circuit consists of a coil of wire connected to a capacitor, or a

self-resonant coil or other resonator with internal capacitance.

- The two are tuned to resonate at the same resonant frequency. The resonance

between the coils can greatly increase coupling and power transfer

19

Resonant inductive coupling can achieve high efficiency at ranges of 4 to 10 times the

coil diameter. This is called "mid-range" transfer, in contrast to the "short range" of

non-resonant inductive transfer, which can achieve similar efficiencies only when the

coils are adjacent. Another advantage is that resonant circuits interact with each other

so much more strongly than they do with non-resonant objects that power losses due

to absorption in stray nearby objects are negligible.

Capacitive Coupling

- Power is transmitted by electric fields

between electrodes such as metal plates.

- The transmitter and receiver electrodes form a

capacitor, with the intervening space as the

dielectric.

- An alternating voltage generated by the

transmitter is applied to the transmitting plate,

and the oscillating electric field induces an

alternating potential on the receiver plate by

electrostatic induction, which causes an

alternating current to flow in the load circuit.

Capacitive coupling has only been used practically in a

few low power applications, because the very high

voltages on the electrodes required to transmit significant

power can be hazardous, and can cause unpleasant side

effects such as noxious ozone production.

The most ambitious project in this field is to add to the smart home system such that,

a coil in the wall or the ceiling of a room; might be able to wirelessly: power lights,

mobiles, clocks, radios, music players and remote controls. Anywhere in the room,

with reasonable efficiency

Another possibility is a charge station similar to the power mat that charges a single

device as a laptop or a mobile or even an electric car.

20

Far Field Transmission

Far field methods achieve longer ranges, often multiple kilometer ranges, where the

distance is much greater than the diameter of the device(s).

Different methods use electromagnetic waves within different wave band. In the early

times, experiments were carried out with radio and microwaves, around 1GHz.

Electric energy is transferred to a strong beam of radio or microwave by a dish-like

antenna, travels through the atmosphere and then received by another antenna which

transfers it back to AC electric current

Types of Far Field Transmission

Microwave

- Radio waves can be made

more directional, allowing

longer distance power

beaming, with shorter

wavelengths of

electromagnetic radiation,

typically in the microwave

range.

- A rectenna may be used to convert the microwave energy back into

electricity. Rectenna conversion efficiencies exceeding 95% have been

realize Power beaming using microwaves has been proposed for the

transmission of energy from orbiting solar power satellites to Earth and the

beaming of power to spacecraft leaving orbit has been considered. ed.

Recently, researchers at the University of Washington introduced power over Wi-Fi,

which trickle-charges batteries and powered battery-free cameras and temperature

sensors using transmissions from Wi-Fi routers.

Laser

Power can be transmitted by converting electricity into a laser beam that is then

pointed at a photovoltaic cell. This mechanism is generally known as "power

beaming" because the power is beamed at a receiver that can convert it to electrical

energy.

It has many advantages like short wavelength (shorter than several micrometers),

good beam width, perfect directionality and non-interference with radio, TV, cell

phone or Wi-Fi signals. But it still has many drawbacks, like relatively lower

efficiency during conversion and atmospheric absorption.

21

Smart Materials

“Smart materials” are materials, systems, and products that behave dynamically,

unlike conventional building materials, which are static. This property allows them to

react and adapt to environmental changes. Their particular characteristics are the

result of physical or chemical influences upon the material, such as different

temperatures or direct sunlight.

Designing your home for energy efficiency will help

you live more comfortably and save money, and help

you save the environment by reducing greenhouse gas

emissions.

An energy smart home takes advantage of the sun’s

free warmth and light, with simple design features to

keep it warm and comfortable in winter, and cool in summer.

Up to 25% of the heat in your home is lost through the roof and up to 35% through

the walls so insulating them gives you the biggest savings on your energy bills.

Cavity and solid walls Houses may be solid walls or cavity walls:

- A cavity wall is made up of two walls with a gap in between, known as the

cavity; the outer leaf is usually made of brick, and the inner layer of brick

or concrete block.

- A solid wall has no cavity; each wall is a single solid wall, usually made of

brick or stone.

Older houses are more likely to have solid walls while the modern are cavity walls but

more expensive.

Insulating your solid walls could cut your heating costs considerably, because solid

walls let through twice as much heat as cavity walls do. The good news is they can be

insulated.

We will focus on solid wall than the cavity wall as it is less expensive and also

efficient.

22

Solid wall insulation Internal or external insulation?

Internal wall insulation is done by fitting rigid insulation boards to the wall, or by

building a stud wall filled in with insulation material such as mineral wool fiber.

External wall insulation involves fixing a layer of insulation material to the wall, then

covering it with a special type of render (plasterwork) or cladding. The finish can be

smooth, textured, painted, tiled, paneled, pebble-dashed, or finished with brick slips.

There are advantages and disadvantages to both.

Internal wall insulation:

- Is generally cheaper to install than external wall insulation

- Will slightly reduce the floor area of any rooms in which it is applied (the

thickness of the insulation is around 100mm)

- Is disruptive, but can be done room by room

- Requires skirting boards, door frames and external fittings to be removed

and reattached

- Can make it hard to fix heavy items to inside walls – although special

fixings are available

- Needs any problems with penetrating or rising damp to be fixed first.

External wall insulation:

- Can be applied without disruption to the household

- Does not reduce the floor area of your home

- Renews the appearance of outer walls

- Improves weatherproofing and sound resistance.

- Fills cracks and gaps in the brickwork, which will reduce draughts

- Increases the life of your walls by protecting the brickwork

- Reduces condensation on internal walls and can help prevent damp (but

will not solve rising or penetration damp)

- Is best installed at the same time as external refurbishment work to reduce

the cost

- May need planning permission - check with your local council

- Requires good access to the outer walls

- Is not recommended if the outer walls are structurally unsound and cannot

be repaired.

23

Roof Insulation: Roof should preferably be insulated from

above. A layer of rigid insulation board can be

added either on top of the roof's weatherproof

layer or directly on top of the timber roof

surface with a new weatherproof layer on top

of the insulation

Energy Efficient Windows:

All properties lose heat through their windows. But energy-efficient glazing keeps

your home warmer and quieter as well as reducing your energy bills. That might mean

double or triple-glazing, secondary glazing, or just heavier curtains.

How energy-efficient glazing works

Double-glazed windows have two sheets of glass with a gap in between, usually about

16mm, to create an insulating barrier that keeps heat in. This is sometimes filled with

gas. Triple-glazed windows have three sheets of glass, but aren’t always better than

double-glazed windows.

Windows Frame materials

For all frame materials there are windows available in all energy ratings.

- uPVC frames last a long time and may be recycled.

- Wooden frames can have a lower environmental impact, but require

maintenance. They are often used in conservation areas where the original

windows had timber frames.

- Aluminum or steel frames are slim and long-lasting, and may be recycled.

- Composite frames have an inner timber frame covered with aluminum or

plastic. This reduces the need for maintenance and keeps the frame

weatherproof.

24

Windows U-values

Windows that have an energy rating will have the u-value of the window displayed on

the energy label. A u-value is a measure of how easily heat can pass through a

material. Materials that let out more heat have higher u-values whereas materials that

let less heat pass through them have lower u-values.

In some cases, windows with a higher energy performance rating might have a higher

u-value than windows with a better energy efficiency rating. This might seem the

wrong way round as lower u-values indicate better insulation levels. However, in

these cases it will be that there are other aspects of the window that make them better

overall such as coating used on the glass and the gap between the glass panes.

Benefits of energy-efficient windows

- Smaller energy bills.

- Smaller carbon footprint.

- More comfortable home: energy-efficient glazing reduces heat loss

through windows and means fewer draughts and cold spots.

- Peace and quiet: as well as keeping the heat in, energy efficient-windows

insulate your home against external noise.

- Reduced condensation: energy-efficient glazing reduces condensation

build-up on the inside of windows.

The costs and savings for energy-efficient glazing will be different for each home and

each window, depending on its size, material and the installer you choose. Double

glazing should last for 20 years or more.

Energy-efficient doors Like any other part of the home, doors can be insulated and draught-proofed to

prevent heat from escaping. New external doors now generally contain integrated

insulation to reduce heat loss.

25

Energy Efficiency Rating of Air Conditioners

Air conditioners efficiencies are greatly affected by the heating and cooling loads

occur in the building because of radiant energy from the sun that enters through

windows, is absorbed by furniture, walls, and equipment, within the building, and is

later radiated as heat within the building and also affected by the heat conducted

through the building envelope (walls, roofs, floors and windows) to or from the

environment around the building.

The efficiencies of air conditioners are usually measured in terms of their Energy

Efficiency Ratios (EER): EER= Btu of cooling / (watt-hours of electric energy input)

The cooling load due to solar radiation through windows can be calculated by :

q =Ƹ(AxSCxMSHGxCLF)

Where q =cooling load (Btu/hr) SC =shading coefficient

A =window area (ft2) CLF =cooling load factor

MSHG =maximum solar heat gain (Btu/hr/ft2)

So by installed building with insulated walls, insulated roof, and double-glazed

windows will decrease the heat conduction through walls and reduce the radiant

energy from the sun so cooling load decrease, efficiency of air conditioner increase

and electric energy input decrease ( Electricity bill will be reduced ).

26

Energy Efficient Lightning:

Lighting accounts for 18% of a typical household’s electricity bill. You can cut your

lighting bill and energy use by changing which bulbs you use and how you use them.

Houses typically use a mixture of standard light fittings and downlights or spotlight

fittings. Energy efficient bulbs are available for both types of fittings.

Which light bulbs are energy efficient?

There are two main types of energy efficient light bulbs which are Compact

Fluorescent Lamps (CFLs) and Light Emitting Diodes (LEDs).

- CFLs are a cost-effective option for most general lighting requirements.

Replacing a traditional light bulb with a CFL of the same brightness will

save energy.

- LEDs are available to fit both types of fittings and are particularly good for

replacing spotlights and dimmable lights. Though more expensive to buy

initially, they are more efficient than CFLs and will save you more money

in the long term. By replacing all halogen down lights in your home with

LED alternatives.

27

References: Godfrey Boyle, Renewable Energy, Oxford University Press, USA, 2004. [2] Lyons,

J.P. ; Robinson, M.C. ; Veers, P. ; Thresher, R.W.,” Wind turbine technology- The

path to 20% US electrical energy”, Power and Energy Society General Meeting -

Conversion and Delivery of Electrical Energy in the 21st Century, 2008 IEEE.

Blaabjerg, F. ; Ke Ma, “Future on Power Electronics for Wind Turbine Systems”,

IEEE Journal of Emerging and Selected Topics in Power Electronics, Volume: 1 ,

Issue: 3, Page(s): 139 – 152, Sep. 2013.

International Energy Agency, Hydrogen Implementing Agreement, Task

17,”Hydrogen

Moran M. J., Shapiro H. N., Fundamentals of Engineering Thermodynamics, 3rd

edition. John Wiley & sons, 2005.

Monitor: Turning wind power on its side. Economist 2006.

Peace S., “Another approach to wind”. The American Society of Mechanical

Engineers. 2004.

Riegler H., “HAWT versus VAWT: small VAWTs find a clear niche”, Refocus,

Volume 4, July 2003, Pages 44–46.

ohn Akwarandu, Department of Electric Power Engineering, Chalmers University of

Technology, Goteborg, Sweden, 2006.

Li, H. ; Chen, Z.“Overview of different wind generator systems and their

comparisons”, Renewable Power Generation, IET, Volume: 2 , Issue: 2, Page(s): 123

– 138, 2008 .

Renewables Global St Shinohara, Naoki (2014). Wireless Power Transfer via

Radiowaves. John Wiley & Sons.

Bush, Stephen F. (2014). Smart Grid: Communication-Enabled Intelligence for the

Electric Power Grid. John Wiley & Sons..

"Wireless energy transfer". Encyclopedia of terms. PC Magazine Ziff-Davis. 2014.

Retrieved December 15, 2014.

Rajakaruna, Sumedha; Shahnia, Farhad; Ghosh, Arindam (2014). Plug In Electric

Vehicles in Smart Grids: Integration Techniques.

Gopinath, Ashwin (August 2013). "All About Transferring Power Wirelessly" (PDF).

Electronics For You E-zine (EFY Enterprises Pvt. Ltd.)

Sazonov, Edward; Neuman, Michael R (2014). Wearable Sensors: Fundamentals,

Implementation and Applications. Elsevier.

28

Wilson, Tracy V. (2014). "How Wireless Power Works". How Stuff Works website.

InfoSpace LLC.

Sun, Tianjia; Xie, Xiang; Zhihua, Wang (2013). Wireless Power Transfer for Medical

Microsystems. Springer Science & Business Media.

Valtchev, Stanimir S.; Baikova, Elena N.; Jorge, Luis R. (December 2012).

"Electromagnetic Field as the Wireless Transporter of Energy" (PDF). Facta

Universitatis Ser. Electrical Engineering (Serbia: University of Niš)

Agbinya, Johnson I. (2012). Wireless Power Transfer. River Publishers.atus Report

(GSR) 2015

Guide to Energy Management.