WIND ENERGY SYSTEMS (WES)
FOR POWER GENERATION
Lecture By
Prof S S Murthy
19th Feb.2015
Silicon Institute of Technology,
Bhubaneswar
National Workshop on
Emerging Technologies in Electrical Engineering,
THERITICAL POTENTION of
Renewable Energy
RENEWABLES

ARE SOMETIMES DESCRIBED AS
• THE “DREAMS OF THE 1970S,
• REALITIES BUT LUXURIES OF 2000,
• AND THE NECESSITIES OF 2020 AND
THEREAFTER”

INCLUDE HYDROPOWER, BIOMASS,
SOLAR, WIND, GEOTHERMAL AND
OCEAN RESOURCES
RENEWABLE POWER CAPACITIES(GW) IN WORLD ,
EU -27, BRICS, AND TOP SIX COUNTRIES , 2012
ALL INDIA GENERATING INSTALLED CAPACITY (MW)
(As on 31-12-14 )
(source: CEA)
GE – Wind Energy
1.5 MW Turbine
WIND ENERGY
GRID CONNECTED
WIND ENERGY SYSTEM
CHITRADURGA-KAR
Global cumulative growth of wind power capacity
Global investment to 2050 (USD billion)
Progress in wind power since
2008
Global wind map, installed capacity and production for lead
countries
Wind generation is significant

In 2010 alone, new global wind power
installations equaled the capacity of 66
large conventional power plants.
World Wind Energy Scenario

TECHNICAL POTENTIAL OF ONSHORE WIND ENERGY IS
ABOUT 20000 TO 50000 TWH PER YEAR AGAINST THE
TOTAL WORLD ELECTRICITY CONSUMPTION OF 15000
TWH

ECONOMIC POTENTIAL DEPENDS ON FACTORS LIKE
AVERAGE WIND SPEED, STATISTICAL WIND SPEED
DISTRIBUTION, TURBULENCE INTENSITIES AND COSTS
OF WIND TURBINE SYSTEMS
WORLD WIND ENERGY
SCENARIO



AS ENERGY OF WIND IS PROPORTIONAL TO
THIRD POWER OF WIND SPEED, ECONOMIC
CALCULATIONS ARE SENSITIVE TO LOCAL
AVERAGE WIND SPEED
BECAUSE THE WIND ENERGY IS INTERMITTENT,
WIND TURBINES MAINLY DELIVER ENERGY BUT
VERY LITTLE CAPACITY.
TYPICAL CAPACITY VALUES BEING OFTEN LESS
THAN 20% OF INSTALLED WIND POWER
WINDIEST REGIONS, POTENTIAL




COASTAL REGIONS OF AMERICAS,
EUROPE, ASIA, AUSTRALIASIA
TOTAL RESOURCE IS VAST- ONE
ESTIMATE PUTS IT AS A MILLION GW
Even if only1% of area used with a low load
factor of 15-40%, wind potential correspond
to total capacity of all elec. Generating plants
Offshore resource HUGE- capable of
supplying all EU electricity without going
further than 30km offshore.
World Wind Energy Scenario


AS THE PENETRATION OF WIND TURBINES
INCREASES THE PERCENTAGE FALLS FURTHER,
REQUIRING EVEN MORE BACK UP POWER FOR A
RELIABLE ENERGY SUPPLY
IT IS POSSIBLE TO TRANSFORM WINDGENERATED ELECTRICITY FROM INTERMITTENT
TO BASE LOAD POWER IF IT IS COMBINED WITH
COMPRESSED AIR ENERGY STORAGE. THUS A
HIGHER CAPACITY FACTOR CAN BE ACHIEVED
WITH SMALL ECONOMIC PENALTY
World Wind Energy Scenario


BY OPTIMIZING THE TURBINE
CHARACTERISTICS TO THE LOCAL WIND
REGIME, CAPACITY FACTOR CURRENTLY
OFTEN AT 20-25% CAN BE OPTIMIZED
WITHOUT LOOSING TOO MUCH ENERGY
OUTPUT.
HOWEVER EXTREME CAPACITY FACTORS
OF ABOUT 40% AUTOMATICALLY MEAN A
LARGE LOSS OF POTENTIAL ENERGY
OUTPUT
World Wind Energy Scenario


BECAUSE OF SCARCITY OF LAND IN
URBAN CENTERS, THE COUNTRIES LIKE
DENMARK, NETHERLANDS, UK AND
SWEDEN ARE DEVELOPING OFFSHORE
PROJECTS
A UNDP STUDY ESTIMATES THAT
AROUND 3000 TWH PER YEAR OF
ELECTRICITY COULD BE GENERATED IN
THE COASTAL AREAS OF EUROPEAN
UNION
World Wind Energy Scenario:
Wind Turbine Sizes

THE CURRENT WIND ENERGY ERA BEGAN
IN MID 1970S WITH A TYPICAL SIZE OF A
WIND TURBINE OF 30 KW WITH A ROTOR
DIAMETER OF 10 METERS

THE LARGEST UNIT INSTALLED TODAY
HAS A CAPACITY OF 1650 KW WITH A
ROTOR DIAMETER OF 66 METERS
ATTRACTIVE WIND REGIONS

Europe- North/West coasts, Mediterranean

Asia- East coast, some inland areas

Africa- North, Southwest coast

North America- Most coastal regions, some
mountainous central zones

S. America- Best Towards south
Wind Energy Scenario

TECHNICAL POTENTIAL OF ONSHORE WIND
ENERGY IS ABOUT 20000 TO 50000 TWH PER YEAR
AGAINST THE TOTAL WORLD ELECTRICITY
CONSUMPTION OF 15000 TWH

ECONOMIC POTENTIAL DEPENDS ON FACTORS
LIKE AVERAGE WIND SPEED, STATISTICAL WIND
SPEED DISTRIBUTION, TURBULENCE INTENSITIES
AND COSTS OF WIND TURBINE SYSTEMS
World WIND ENERGY Scenario

WIND ENERGY WAS USED AS A SOURCE OF
POWER BEFORE THE INDUSTRIAL REVOLUTION

DISPLACED BY FOSSIL FUELS BECAUSE OF COST
AND RELIABILITY

OIL SHOCKS OF 1970S SAW RENEWED INTERESTS
IN WIND ENERGY FOR APPLICATIONS LIKE GRIDCONNECTED ELECTRICITY, WATER PUMPING AND
POWER SUPPLY IN REMOTE AREAS
Wind Power Global Capacity, 19962012
Wind Power Capacity and additions,
Top 10 Countries, 2012
Introduction
Wind Turbine Suppliers
Sinovel Others
Nordex 3.4%
3.4%
Goldwind
4.2%
Vestas
22.8%
Acciona
4.4%
Siemens
7.1%
GE Wind
16.6%
Suzlon
10.5%
Enercon
14.0%
Gamesa
15.4%
Top 10 wind turbine suppliers in 2007
• Account for around 95% of the total supply in 2007
• Asian manufacturers improve their shares
(Goldwind & Sinovel in China, Suzlon in India)
26
Wind Power in India





Estimated Potential as per CWET: 65-100 GW
Renewable share (31 GW) in overall Power
Capacity (234 GW) amounts to more than 13%
Share of Wind power generation in Indian
Renewables is 65 %.
India is fifth after USA, Germany, Spain, China
NOTE: Only about 20% is the maximum utility
factor of installed wind capacity based on local
wind conditions.
WIND POWER – State Wise
Analysis in INDIA
Wind Power Potential in India
Estimated Gross Potential
NAPCC - National Action Plan on Climate Change
REC - Renewable Energy Certificate
SERCs - State Electricity Regulatory Commissions
SNA - State Nodal Agency
IPP - Independent Power Projects
Wind Turbine Technology
Wind turbine size
Year
Capacity (kW)
Rotor Diameter (m)
1985
50
15
1989
300
30
1992
500
37
1994
600
46
1998
1,500
70
2003
3,000
90-104
2004
4,500-5,000
112-126
2007
6,000
127
49
MODERN WIND TURBINES

Early machines (20 Yrs. Ago)- 50-
100kW, 15-20m dia

Present trend-upto 2MW and above, 60-
70m dia

Offshore upto 5MW and 110m.dia
Wind Turbine Technology
Horizontal- and vertical-axis wind turbines
Rotor Diameter
Rotor
blade
Generator
Nacelle
Rotor
Diameter
Tower
Gearbox
Rotor
blade
Tower
Gearbox
Horizontal-axis wind turbine (HAWT)
Generator
Vertical-axis wind turbine (VAWT)
52
Wind Turbine
Offshore Wind Farm
Fixed-bottom foundation and floating offshore
concepts
Wind farms
REQUIREMENTS

Area required per Wind Turbine = 5Acres (approx)
Grid availability.

Accessibility for commissioning.

Strong terrain / soil for proper foundation / civil work

Favorable environmental condition to prevent
corrosion & not prone to cyclone.

Wind farms

Cluster of tens of machines or many
single machines

Economy of scale dictates wind farms-
civil Engg and grid connection cost
decreases
SITING AND CLEARANCES
GCIG IN WIND SYSTEM
INSIDE NECELLE(RRB
VESTAS)
Enercon System(SYN.GEN)
GENERATORS AND SYSTEMS

FIXED SPEED
•
•

INDUCTION GENERATOR(MOSTLY)
SYNCHRONOUS GENERATOR
VARIABLE SPEED WITH POWER ELECTRONIC
CONVERTORS-AC/DC/AC
•
•
Doubly Fed Induction Generator (DFIG)
Permanent Magnet Synch. Generator- Direct Driven
Gearless
Wind Energy Conversion
WES without using power converters
Up to 2.3 MW
SCIG
Soft
starter
Squirrel Cage
Induction Generator
Gearbox
Capacitor Transformer Grid
Advantages
•
•
Low manufacturing cost
Robust, low maintenance cost
Drawbacks
•
•
Low conversion efficiency
Large fluctuation in output power
65
Wind Energy Conversion
Doubly fed induction generator with rotor converter
Up to 5 MW
DFIG
Gearbox
Reduced-capacity
converter
Transformer Grid
Advantages
•
Extended speed range
•
High system efficiency and low cost because
•
Decoupled active & reactive power control
•
Enhanced dynamic performance
Drawbacks
•
Limited grid-fault operation capability
66
Wind Energy Conversion
Wind energy systems with full-power converters
Up to 5 MW
(PMSG)
SCIG
Gearbox WRSG
PMSG
Full power
converter
Transformer Grid
Advantages
•
The generator fully decoupled from the grid
•
Wide speed range
•
Smooth grid connection
•
Reactive power compensation
•
Capability to meet the strict grid code
Drawbacks
67
FIXED SPEED WIND SYSTEMS
SCHEMATIC OF A CONSTANT
SPEED WIND SYSTEM
11kV
P
WIND
P
INDUCTION
415V
GEAR BOX
TURBINE
GENERATOR
11kV
Q
TRANSFORMER
CAPACITOR
GRID
Enercon wind system

E-48 TECHNICAL DATA
Rated capacity : 800 kW
Rotor diameter : 48 m
Hub height : 56.85m and 74.85 m Rotor with
Pitch Control
Type : Upwind rotor with active pitch control
Direction of rotation : Clockwise
Number of blades : 3
Length of blades : 20.7 m
DATA…

Swept area : 1810 m²
Blade material : Fiberglass (reinforced epoxy) with
integral lightning protection
Rotor speed : Variable, 16-31.5 rpm
Tip speed : 41 - 78 m/s
Pitch control : Three synchronized blade pitch
system with battery back-up
Enercon System….

Generator : Synchronous - Type
Hub : Rigid
Bearings : Tapered roller bearings
Grid Feeding : AC-DC-AC through Convertor Invertor
Braking System : 3 independent Aero Brakes
with emergency back up supply.
Yaw Control : Active through adjustment gears,
friction damping
Cut-in Wind Speed : 2 m/s
Rated Wind Speed : 14 m/s
Tower : Steel Tubular / Concrete
POWER RELATION-WIND

P= ρCp D2 w3
• ρ = AIR DENSITY
• Cp= CONSTANT
• D= BLADE DIA
• w =WIND SPEED
POWER Vs WIND SPEED
Pitch Control
1.0
Cut out
.p.u
speed
power
5
Cut in speed
10
20
15
25
Wind speed, m/s
DOUBLY WOUND SCIG AS
WIND GENERATOR (NO
CONVERTOR)
GRID
DATA ON A WIND MACHINE

Rated Power:1.65 MW

Blade dia: 63m

Cut in speed:3-5 m/s

Cut out speed: 20-25 m/s
Energy production (MWh)

Wind speed (m/s)
Energy
at 60 m height5m/s-
1500
7m/s
3700
8m/s
4800
GRID INTERFACE

SEVERAL PROBLEMS OF EVACUATION
OF ENERGY INTO THE GRID

HIGH WIND AND LOW LOAD
CONDITIONS

WEAK , UBNORMAL GRIDS

SEVERAL STUDIES MADE
GRID CONNECTED
INDUCTION GENERATOR
COMPARISON- MOTOR Vs
GEN
MOTOR
GENERATOR
STATOR VOLTAGE
VS
VS
STATOR CURRENT
IS
-IS
MAGNETIZING
CURRENT
IM
IM
AIRGAP VOLTAGE
VG
VG
MOTOR Vs GEN.
MOTOR
GENERATOR
ROTOR
CURRENT
IR
-IR
SLIP
s
-s(=s')
AIR GAP
POWER (Pg)
R
3 I 2r r
s
3 I 2r
Rr
s'
Motoring and Generating
MOTOR
Pshaft
DEVELOPED
TORQUE (Td)
SPEED (pu)
GENERATOR
2
r
3I R r
1  s
Pout 
ωs s
3I 2r R r
ωs s
υ  1 s
Pin
3I 2r R r
1  s'

ωs s'
op p to Po u t
3I 2r R r 3I 2r R r


ωs s
ωs s'
υ  1  s'
Motoring/Generating
MOTOR
Pmech
Pelec
GENERTOR
2
r
3I R
1  s 
ωs s
3Vs Is coss
3I 2r R
1  s'
ωs s
3Vs Is coss
MOTOR

GENERATOR
Pmech
Load
Pg
Tin
Pout
Td
ν
TL
Pelec
Pelec
Pg
Td
ν

Pm
Pin
PRIME
MOVER
GRID CONNECTED INDUCTION
GENERATORS DRIVEN BY WIND/HYDRO
TURBINES

Induction Generators ( I G ) are used for low
and medium power generation, as they
have certain inherent advantages over
conventional alternators

Low unit cost

Less maintenance

Rugged and brushless rotor

Asynchronous operation

THE INPUT POWER TO THE GENERATOR CAN BE
NORMALLY KEPT CONSTANT WITH HYDRO
TURBINES.

THE WIND TURBINE ON THE OTHER HAND
PROVIDES VARYING POWER INPUT DEPENDENT
ON THE WIND SPEED.

CAPACITORS ARE CONNECTED TO THE
GENERATOR TERMINALS , TO IMPROVE THE
SYSTEM POWER FACTOR AND TO REDUCE THE
VAR DRAIN FROM THE GRID
PROBLEM WITH THE GRID






GRID FAILURE
SINGLE PHASING
TURBINE OVERSPEED WITH LOAD THROW
OFF(ABOVE 2pu)
GENERATOR THERMAL OVERLOAD
POOR POWER QUALITY OF GRID-VOLTAGE,
FREQUENCY
SELF EXCITATION DUE TO CAPACITOR DUE TO
GRID FAILURE AND TURBINE OVERSPEED
Grid connected induction
generator
EQUIVALENT CIRCUIT OF IG
FIND RESPONSE AT CONSTANT POWER
INPUT AND GRID VOLTAGE

USE THEVENIN EQ. CIRCUIT
THEVENIN EQUIVALENT
CIRCUIT

Pin=- 3Ir2 Rr (1-s)/s…………(1)

Vth+ (Rth+ Rr /s +j Xth ) Ir =0……….(2)

ABOVE ARE TWO EQS WITH TWO
UNKNOWNS s AND Ir

FROM FIG.
 Ir=
Vth / {[Rth + Rr /s ]2 + Xth2} 1/2
SIMPLIFYING

As2 +Bs + C =0

A= Rth2 + Xth2 - 3Vth 2/ Pin

B=2Rth Rr +3 Vth / Pin
C= Rr 2
 Pin=-
3Ir2 Rr (1-s)/s
 SINCE
s IS NEGATIVE Pin IS
POSITIVE






SOLVE FOR s, FOR GIVEN POWER
INPUT AND GRID VOLTAGE
SOLVE EQ. CIRCUIT
GET ACTIVE POWER
REACTIVE POWER
POWER FACTOR
EFFICIENCY
DATA ON PRACTICAL FIELD
SYSTEMS






GENERATOR- 415V, 50 Hz
GRID-11kV, 50 Hz
TRANSFORMER IMPEDANCE(0.021+j0.382)p.u
HV- TRANS. LINE IMPEDANCE(0.021+j0.382)Ohm/km
SC MVA OF GRID = 250
LENGTH OF HV LINE=10km (HYDRO),
2km(WIND)
EQ. CKT. PARAMETERS(pu)
M/C
Rs
Rr
xls
xlr
xm
Rc
1
0.0135
0.024
0.105
0.169
3.34
72.2
2
0.19
0.0164 0.069
0.087
3.0
47.85
3
0.0504
0.0493 0.076
0.132
2.35
32.8
4
0.031
0.0256 0.0657
0.094
2.08
42.5
5
0.0492
0.031
0.179
3.19
52.42

0.933
CHARACTERISTICS OF WIND
TURBINE DRIVEN 55/11KW
INDUCTION GENERATOR
EFFECT OF VARIATION OF GRID
VOLTAGE
EFFECT OF VARIATION OF GRID
VOLTAGE
EFFECT OF VARIATION OF GRID
VOLTAGE
EFFECT OF VARIATION OF TERMINAL CAPACITOR
EFFECT AT VARYING POWER INPUT
EFFECT AT VARYING POWER INPUT
EFFECT AT VARYING POWER INPUT
EFFECT AT VARYING POWER INPUT
References..



S.S.Murthy (with C.S.Jha and P.S.N.Rao), "Analysis of Grid
Connected Induction Generator driven by Hydro/ Wind
Turbines under Realistic System Constraints ", IEEE Trans.
on Energy Conversion, March, 1990 Volume 5, No. 1, pp 1-7
S.S.Murthy (with A.H.Ghorashi, B.P.Singh & Bhim Singh),
'Analysis of Wind Driven Grid Connected Induction
Generators under unbalanced Grid Conditions', IEEE Trans.
on Energy Conversion Vol.9, No.2, June, 1994 pp 217-223
S.S.Murthy (with C.S.Jha, A.H.Ghorashi, P.S.Nagendra Rao),
'Performance Analysis of Grid Connected Induction
Generators Driven by Hydro/Wind Turbines including Grid
Abnormalities', presented at Inter Society Energy Conversion
Engg. Conference (IECEC at Washington DC, Aug., 1 989).
VARIABLE SPEED WIND SYSTEMS
DOUBLY FED
INDUCTION GENERATORS:
DOUBLY FED IND. MACHINE
GRID
Pe
f
Pcur Pg
Pcus
DFIG
Pr
fr
TRANSFORME
Pm
f
CONVERTOR(BIDIRECTIONAL))
EQUIVALENT CIRCUIT of DOUBLY
FED WOUND ROTOR I.M- MOTRING
Is
Rs
Vs
I0
jxls
Vg
Rr+jsXlr
Rc
Ic
Ir
xm
Im
sVg
Ej

sPg= Pr + Pcur

Pg= Pr + (1-s) Pg +Pcur
ROTOR EQUATION

sVg- Ir(Rr+jsxlr)-Ej=0

sVg= Ir(Rr+jsxlr)+Ej

sVg-Ej = Ir(Rr+jsxlr )

(Ej REF. TO STATOR TURNS)
DFIG
DFIG (COVERTOR IN ROTOR)
POWER SPEED CURVES
80
Turbine Power (kW)
Vw=11m/s
V =10m/s
60
w
V =9m/s
w
Maximum Power Line
40
V =8m/s
w
V =7m/s
w
V =6m/s
w
V =5m/s
20
0
0
w
1
2
3
4
5
6
7
Generator Speed (rad/sec)
Mechanical power output of the wind turbine vs. generator speed for different wind speeds
PHASOR DIAGRAM WITH
INJECTED EMF
Ej
β
sVg
Φr
Ir

RESOLVE VOLTAGES AND DROPS
ALONG Ir AXIS

sVg cos Φr= Ir Rr+ Ej cos (Φr + β)

sVg Ir cos Φr= Ir2 Rr+ Ir Ej cos (Φr + β)

ON 3- PH BASIS

Pg= 3 Vg Ir cos Φr

Pcur=3 Ir2 Rr

Pr= POWER FED TO CONVERTOR

=3 Ir Ej cos (Φr + β)

AIRGAP POWER=
• ROTOR COPPER LOSS+ POWER FED TO
CONVERTOR + MECHANICAL POWER
EXAMPLE







s= - 0.2
Pg=+100
Pm, = +120
Pr =-20 (POWER FED TO ROTOR)
Pe, = +100
POWER DRAWN FROM GRID
=Pgrid = 120
MODE-I, SUBSYNCHRONOUS,
MOTORING

0<s <1, s IS +VE

Pg, Pm, Pe, Pr POSITIVE

Pm =(1-s) Pg IS POSITIVE

NEGLECT LOSSES Pcur, Pcus
EXAMPLE







s= +0.2
Pg=+100
Pm, = +80
Pr =+20
Pe, = +100
POWER DRAWN FROM GRID
=Pgrid = 80
MOTORING AT s=0.2
GRID (80)
Pe
f
(100)
Pcur
Pcus
Pg
(100)
DFIG
Pr
(20)
fr
CONVERTOR
Pm(80)
f
TRANSFORMER
MODE-II, SUPERSYNCHRONOUS,
MOTORING

-1<s <0, s IS NEGATIVE

Pg, Pm, Pe, POSITIVE

Pr NEGATIVE

Pm =(1-s) Pg IS POSITIVE

NEGLECT LOSSES Pcur, Pcus

Pm IS MORE THAN Pg
MOTORING AT s= -0.2
GRID (120)
Pe
f
(100)
Pcur
Pcus
Pg
(100)
DFIG
Pr
(-20)
fr
CONVERTOR
Pm(120)
f
TRANSFORMER
MODE-III, SUBSYNCHRONOUS,
GENERATING

0<s <1, s IS +VE

Pg, Pm, Pe, Pr NEGATIVE

Pm =(1-s) Pg IS NEGATIVE

Pm IS LESS THAN Pg
EXAMPLE







s= + 0.2
Pg=-100
Pm, = -80
Pr =-20 (POWER FED TO ROTOR)
Pe, = -100
POWER FED TO GRID
=Pgrid = 80
GENERATING AT s= +0.2
GRID (-80)
Pe
(-100)
Pcur
f
Pg
Pcus
TRANSFORMER
Pm(-80)
MOTORING
(-100)
DFIG
Pr
(-20)
fr
CONVERTOR
f
GENERATING
MODE-IV, SUPERSYNCHRONOUS,
GENERATING

-1<s <0, s IS NEGATIVE

Pg, Pm, Pe, NEGATIVE

Pr POSITIVE

Pm =(1-s) Pg IS NEGATIVE

Pm IS MORE THAN Pg
EXAMPLE







s= - 0.2
Pg=-100
Pm, = -120
Pr =+20 (POWER DRAWN FROM ROTOR & FED
TO GRID)
Pe, = -100
POWER FED TO GRID
=Pgrid = 120
GENERATING AT s=-0.2
GRID (-120)
Pe
(-100)
Pcur
f
Pg
Pcus
TRANSFORMER
Pm(-120)
GENERATING
(-100)
DFIG
Pr
(+20)
fr
CONVERTOR
f
POWER Vs SLIP (MOTORING)
Pm
Pg
Pr
s
0
-1
s
POWER Vs SLIP, GENERATING
-1
0
s
Pr
0
Pm
s
Pg
Pg
Pm
Pr
MOTOR
SUB
SYNC
+
+
+
MOTOR
SUPER
SYNC
+
+
-
GENERATOR
SUB
SYNC
-
-
-
GENERATOR
SUPER
SYNC
-
-
+
PM GENERATORS
WIND SYSTEM WITH
PM GENERATOR
RECTIFIER
INVERTER
TRANSFORM
WHAT IS IN STORE FOR
FUTURE?
FUTURE IN WIND ENERGY

FIXED SPEED SCIG (UPTO 1 MW)

VARIABLE SPEED SCIG (WITH
CONVERTOR/INVERTOR BETWEEN MACHINE AND
GRID

DFIG (FEW MW)

SYNCH GEN LOW SPEED GEARLESS WITH AC-DC-AC

PM SYNCH GEN WITH AC-DC-AC
FUTURE IN INDIA

NEW PREDICTION: 100GW

INCREASE HEIGHTS

RETROFIT OLD FARMS

WIND FORECASTING

OFF-GRID

OFF-SHORE (HUGE POTENTIAL)
FUTURE DEVELOPMENTS




GERMANY, DENMARK- SLOWED
DOWN
USA, SPAIN,INDIA, CHINA FORGING
AHEAD
CANADA, MIDDLE EAST, FAR EAST,
S. AMERICA HAVE GOOD PLANS
At current growth 150GW of wind
power expected in 2010
FACTORS FOR GROWTH

POLITICAL SUPPORT

INTERNATIONAL COMMITMENT

CONCERN FOR CLIMATE CHANGE, EMISSIONS

TECHNOLOGY FAIRLY MATURE

PERFORMANCE AND COST ARE NOW CRUCIAL
THANK YOU