It Blows You Away

"Coal, gas and oil will not be the three kings of the energy world for ever. It is no longer folly to look up to the sun and wind, down into the sea's waves"

Introduction

Energy is a major input for overall socio-

economic development of any society

The prices of the fossil fuels steeply increasing

So renewables are expected to play a key role

Wind energy is the fastest growing renewable

Wind turbines are up to the task of producing

serious amounts of electricity

Principles

Uneven heating of earth’s surface and rotation

Force Strength km/h Effect

0 Calm 0-1 Smoke rises vertically

1 Light air 1-5 Smoke drifts slowly

2 Light breeze 6-11 Wind felt on face; leaves rustle

3 Gentle breeze 12-19 Twigs move; light flag unfurls

4 Moderate breeze 20-29 Dust and paper blown about; small branches move

5 Fresh breeze 30-39 Wavelets on inland water; small trees move

6 Strong breeze 40-50 Large branches sway; umbrellas turn inside out

7 Near gale 51-61 Whole trees sway; difficult to walk against wind

8 Gale 62-74 Twigs break off trees; walking very hard

9 Strong gale 75-87 Chimney pots, roof tiles and branches blown down

10 Storm 88-101 Widespread damage to buildings

11 Violent Storm 102-117 Widespread damage to buildings

12 Hurricane Over 119 Devastation

Beaufort Scale

Velocity with Height

Power vs. Velocity

Lift and drag forces

Solidity and Tip speed ratio

Performance co-efficient and Betz criterion

Potential

Huge potential exists

Available potential can contribute five

times the world energy demand

0.4% contribution to total energy

Wind is currently the world’s fastest growing energy source

Growth of Wind EnergyM

W I

nsta

lled

Year

Wind Energy generating capacity by country, 1980-2003

Installed Capacity (MW) in 2005

Available potential in India

Wind Power Density of India

All India Fuel wise Installed Capacity, 2004

Hydro 26%

Gas10%Coal

58%

Nuclear2%

Wind3%

Diesel1%

Installed capacity (MW) in India

0

500

1000

1500

2000

2500

3000

3500

4000

90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05

State wise potential in India, 2005

0

2000

4000

6000

8000

10000

Gross Potential 8275 9675 6620 875 5500 3650 1700 5400 3050 450

Installed Capacity 120.6 253.53 410.75 2 28.85 456.15 2 284.76 2040.3 1.1

APGujara

tKarnat

akaKerala MP

Maharashtra

OrissaRajast

hanTN WB

MW

Technology

Turbine Evolution

Used for

• Pumping water

• Grinding grain

Mainly used for

• Generating Electricity

Types of turbines

VAWT

Drag is the main force

Nacelle is placed at the bottom

Yaw mechanism is not required

Lower starting torque

Difficulty in mounting the turbine

Unwanted fluctuations in the power output

HAWT

Lift is the main force

Much lower cyclic stresses

95% of the existing turbines are

HAWTs

Nacelle is placed at the top of the tower

Yaw mechanism is required

Two types of HAWT

DOWNWIND TURBINE UPWIND TURBINE

Counter Rotating HAWT

Increase the rotation speed

Rear one is smaller and stalls at high

wind speeds

Operates for wider range of wind speeds

Offshore turbines

More wind speeds

Less noise pollution

Less visual impact

Difficult to install and maintain

Energy losses due long distance

transport

A Typical HAWT

Turbine design and construction

Blades

Material used

Typical length

Tower height

Heights twice the blade length are

found economical

Number of blades

Three blade HAWT are most efficient

Two blade turbines don’t require a hub

As the number increases; noise, wear and

cost increase and efficiency decreases

Multiple blade turbines are generally used

for water pumping purposes

Rotational control

Maintenance

Noise reduction

Centripetal force reduction

Mechanisms Stalling

Furling

Yaw Mechanism

To turn the turbine against the wind

Yaw error and fatigue loads

Uses electric motors and gear boxes

Wind turbine safety

Sensors – controlling vibrations

Over speed protection

Aero dynamic braking

Mechanical braking

Improvements Concentrators

Future Wind TurbinesWind Amplified Rotor Platform

Disc type wind turbine

o Much more efficient than

HAWT

o Requires less height

o Low noise

o Works in any wind direction

Economics

Determining Factors

Wind Speed

Turbine design and construction

Rated capacity of the turbine

Exact Location

Improvements in turbine design

Capital

Wind Speed Matters

Assuming the same size project, the better the wind resource, the lower the cost.

Size Matters

Assuming the same wind speed of 8.08 m/s, a large wind farm is more economical

Overall cost distribution

Break down of capital cost

Energy Cost Trend

1979: 40 cents/kWh

Increased Turbine Size

R&D Advances

Manufacturing Improvements

2004: 3 – 4.5 cents/kWh

2000:4 - 6 cents/kWh

Typical cost statistics

Size: 51 MW

Wind Speed: 13-18 miles/hour

Capital cost: $ 65 million ($1300/MW)

Annual production: 150 million kW-hr

Electricity costs: 3.6-4.5 cents

Payback period: 20 years

Economic Advantages

Greater fuel diversity

No delay in construction

Low maintenance costs

Reliable and durable equipment

Additional income to land owners

More jobs per unit energy produced

No hidden costs

Future

Wind Capital Cost

Cost of Wind Energy

Germany now and 2020

At present 10% of the country’s energy is supplied by wind energy

By 2020 it is expected to go up to 26%

Australia now and 2040

So…..

Price of wind power is coming down

There is enormous capacity

Energy storage, however, is still a problem

Typical Concerns

Visual impact Off shore turbines

Arrangement

Avian concerns Suitable choice of site

Using tubular towers instead of lattice tower

Using radars

Noise Varies as 5th power of relative wind speed

Streamlining of tower and nacelle

Acoustic insulation of nacelle

Specially designed gear box

Use of upwind turbines

Reducing angle of attack

Low tip speed ratios

Changes in wind patterns

Reducing turbulence

Intermittent

Coupling with hydro or solar energy

TV, microwave, radar interference

Switching from conducting material to

non-conducting and composite material

Conclusion

Wind energy is pollution free and nature

friendly

Wind energy has very good potential and it is

the fastest growing energy source

The future looks bright for wind energy

because technology is becoming more

advanced and windmills are becoming more

efficient

THANK YOU

Furling