Wind Lecture -1- History&Targets

Wind Energy and Wind Turbine Technology

Renewable Energy Technology II

Advanced Course MJ2412 (RET 2)Advanced Course MJ2412 (RET-2)

Lecture series on WIND POWER

Miroslav PetrovDepartment of Energy Technology,p gy gy,

Royal Institute of Technology, Stockholm, Sweden

Dept. of Energy Technology, Stockholm, Sweden. Course RET II (MJ2412) 1

Structure of the lecture series

Introduction – historical review and latest trends.

Basic wind turbine aerodynamics – understanding how they work.

Machine elements and electrical generators for wind turbines –important characteristics.

Operation of wind turbines – Turbine output in real applications. Operational characteristics. Energy yield. Maintenance issues.

Environmental Aspects – issues related to the impact of wind power.


Section 1

Brief Historical Review

– Wind turbines were the locomotives of refined engineering long before the steam engines and the industrial revolution.


Ancient Windmills

Large drag-force vertical axis devices, used in the Middle East, Central Asia and China for milling grain or pumping water. p p g

Need steady winds from one direction only.

Date back more than 3000 years.

Source: www.eurowind-uk.net


Ancient Windmills – still in operation

Source: Deutsches Museum


First Windmills in Europe

”Tower mills” appeared on the Mediterranean coasts ~ 1000 years ago. y g

Solid stone structures, again facing only one certain di ti f ili i ddirection of prevailing winds.

Source: ”Wind Power Plants”, R. Gasch & J. Twele


Improved Technology:gyPost (Pole) Mills

The wooden 4-bladed windmill was developed pand widely used in Medieval Europe

Source: Deutsches Museum


First “scientific” approach

John Smeaton, in 1759, , ,experimented on wind rotors with his revolutionary test apparatus.apparatus.

He proved the 4-bladed rotor’s superior performance at that time, and defined the ”twisted wing”.

Source: www. windturbine-analysis.com


Yawing the turbinegThe pole mill was resting on a pole in order to be able to yawpole in order to be able to yaw (facing the wind).

The mill was yawed by hand. y y

Source: www.windmillworld.comSource: www.molendatabase.nl


Further Improvements

Windmills grew in size and got further sophisticated.

Th bl d i d fThe blade is a wooden frame covered with sail cloth or wooden plates.

Source: www.molendatabase.nl


Yaw Levers for large windmillsg

Some windmills (or windpumps)Some windmills (or windpumps) grew to enormous sizes, but yawing was still manual.

Source: www.molendatabase.nl


Mechanical Yawing: the Fantailg

I t t t f d thImportant step forward – the introduction of forced yawing propelled by a rosette (fantail).

Source: www.eurowind-uk.net

Source: www. members.ozemail.com.au

Source: www.windmillworld.com


Internal construction of the mill

Wooden drivetrain andWooden drivetrain and wooden gears rotating the milling stone. Source: www. members.ozemail.com.au

Source: ”Wind Power Plants”, R. Gasch and J. Twele


Power Output Control

Power output in strong winds was regulated by yawing the rotor out of wind, then uncovering the cloth on the blades by climbing on them, after which the mill was ready to be yawed back in action. y

Source: www members ozemail com au


Source: www. members.ozemail.com.au

The Multiblade WindpumpSource: www.molendatabase.nl

The multiblade ”western farm mill” (water pump) was a breakthrough for simplicity of construction, maintenance,simplicity of construction, maintenance, and output control in the 19th century.

A simple tailvane for yawing, and a special side-vane for turning

Source: www windturbine-analysis com

out of wind at high windspeeds...


Source: www.windturbine analysis.com

Multiblade windpump applications

L d hi h t t biLow-speed high-torque turbine, always coupled to the load. The blades are curved steel plates.

Source: ”Wind Energy Systems”, Gary L. Johnson

The load is a piston pump.

Source: www.windpower.org


First attempt for electricity generationy g

Poul la Cour’s turbine in 1904Poul la Cour s turbine in 1904, Denmark, used an old-style rotor with a DC generator, and was the first one to producewas the first one to produce electricity.

Source: www.afm.dtu.dk/wind


Modern Experiments (1)( )

The Smith Putnam turbineThe Smith-Putnam turbine in Vermont, USA, 1940, was the first one to introduce

f il bl d ithproper aerofoil blades with a rotor diameter of 53 m, and to attempt a power

t t f 1 MW !output of 1 MW !

Source: www.integener.com


Source: www.integener.com


The 200 kW Gedser turbine i D k 1957 ith tin Denmark, 1957, with rotor diameter of 24 m, showed that further development will be governed mostly by possibility to manufacture better, larger, and lighter blades!





TVIND turbine in Denmark, 1977, had an installed capacity of 2 MW with rotor diameter of 52 m.




The WTS-4 project turbine in USA, 1981, had a generator of 4 MW, but the rotor diameter was too small (78 m) and the turbine hardly ever operated at its rated capacity. p y




The MAGLARP turbine in Sweden, 1982, had a rated capacity of 3 MW and operated reliably for 11 years It was the most productive turbine amongyears. It was the most productive turbine among all early large experimental projects.

Source: www.ieawind.org



The Eole C ertical a isThe Eole C vertical axis Darrieus turbine in Cap Chat, Québec, 1987, was 100 m hi h ith t f 64high with a rotor of 64 m diameter, and had a rated capacity of 4.2 MW, the largest at that time.

Source: www.windpower.dk



The 3MW WEG-LS1 turbine on Burgar Hill (Orkney Islands) in the UK 1988Islands) in the UK, 1988, costed 17 million £ !!!...

Source: www.stockscotland.com


To learn from one’s mistakes

The quest for designing and installing super-large experimental turbines continued in Denmark, USA, Germany, Britain, Italy, Spain, Japan, etc..

Valuable experience was gained many possibleValuable experience was gained, many possible failure points and technical hinders identified.

But for the windpower to enter a commercialBut for the windpower to enter a commercial breakthrough, some new, reliable, lower cost solutions were required!q


The evolution approach

Learn first how to make small reliable machines, and after that you may let them evolve into larger ones…

Manufacturers in Denmark emerged around 1980 and started producing series of small wind turbine

d l (20 50 kW) d f th k tmodels (20–50 kW) ready for the market.

The first mass-market for wind power was launched in the early 1980’s in California following the second oil crisis, which triggered the introduction of favourable legislation for promoting renewable energy sourceslegislation for promoting renewable energy sources. Wind power became competitive and started to grow.


First commercial windmills

California’s windparks:California s windparks:

First machines (up to 100 kW) were mechanically inferior and had the bad luck of getting morally old and obsolete before managing to serve their designed lifetime.

Source: www.nordex.dkSource: www.nordex.dk

Source: www.wind-works.org


Technological Developmentg

•Wind turbines continuously grow in unit size.

•Costs of wind-generated electricity are becoming competitive to those from newly built fossil-fired plants.

•Further growth in size is dependant not only on the possibility to produce longer blades, but also on electrical power aspects and load management.

•Further deployment of wind turbines must utilize the huge offshore wind resources and find a solution for ffi i t id i t ti d/ tefficient grid integration and/or energy storage.


Largest wind turbines todayg y

Th l t i lThe largest commercial wind turbine for onshore installations is the Enerconinstallations is the Enercon 4.5 MW machine, with rotor diameter of 114 m!

First prototypes of 5 MW turbines, designed for offshore applications, are currently being tested by several companiesseveral companies.

Source: www.enercon.de


Complexity of modern wind turbinesy

Large modern wind turbines involve all these fields:

Aerodynamics (blades and structures);

Mechanics (machine elements strength ofMechanics (machine elements, strength of materials, novel materials, testing);

Electrical Engineering (electrical machines, grid connection/integration, load management);

Electronics (controls and power electronics);

Controls (control theory, hydraulics, pneumatics);

Civil Engineering (foundations, roads, power lines);


Transport Logistics; Design & Architecture;

Economics; Project Planning & Management...


Section 2

Overview of wind energy realitiesOverview of wind energy realities

– the explosive development of windpower during the last 30 years, and its importance for the present & future energy mix in the worldp p gy


Importance of Renewable Energygy

”Old” renewable energy targets in the EU:

Source: www ewea orgSource: www.ewea.org Surpassed already by the end of 2005 !


Renewable Energy Targetsgy g

EU: 12% renewable energy by 2010 (incl. 75’000 MW wind power)

EU: 20% renewable energy by 2020 (incl. 180’000 MW wind power)

USA: 20% electricity from wind by 2030

Greenpeace wishes globally: 12% electricity from wind by 2020Greenpeace wishes globally: 12% electricity from wind by 2020

EU: Investments of ≈ 443 billion € are required until 2020.

More than 2’000’000 new jobs can be createdMore than 2 000 000 new jobs can be created.


Incentives for reaching the targetsg g

Various investment grant schemes have been offered in the earlyVarious investment grant schemes have been offered in the early years. Later on, a secured electricity price scheme for the investor has been enough to trigger the development.

Nowadays, several types of support schemes are still in action, though their importance is decreasing as wind power becomes more and more competitive.

The three major support schemes used today are:j y

•Fixed Feed-in Price for renewable electricity;

•Fixed Quantity of Renewable Electricity (“Green Certificates”);y y ( );

•Tax Credits (the “Production Tax Credit” in the USA).


Support Schemes

•Fixed price (feed-in tariff): Guaranteed price per kWh. The higher costs are covered by the end users. This is the most promotional scheme, perfect examples are Denmark, Germany, and Spain, featuring the highest penetration of wind power. Other countries have also tried to use

t d i b t ff f bl ith id ti dguaranteed prices, but suffer from problems with grid connection and power regulation.

•Fixed quantity system (Green Certificates or Renewable Obligation Certificates): Involve a decision by national governments about the level of renewable electricity to be achieved over a certain period, while market forces are left to establish the price per kWh. Tradable certificates are

li d t fl t th dditi l t (UK I l d S d It l t )applied to reflect the additional costs (UK, Ireland, Sweden, Italy, etc.), which again are ultimately covered by the end users.

•Production Tax Credit (PTC): Used in the USA and other North- and South-American countries. A federal support in cents/kWh is applied to the power producer, which is not directly transferred to the end user.


The Danish Example

A success story for Danish industry:

22% i 2009!~22% in 2009!

Denmark is the largest producer and exporter of wind turbines (per capita), p (p p ),and has the largest share of electricity consumption covered by wind...!


Market Development in EuropeAnnual wind power capacity growth in Europe [MW]:

Source: www.ewea.org


Europe – 2002



Europe – 2003


Europe – 2004


Europe – 2005


Europe – 2006


Europe – 2007

Source: www ewea org



Europe – 2008



Europe – 2009



Europe – 2010



Market development in the USAEverything began in California…

f SAnnual growth of wind turbine capacity in the USA, [MW]:

Source: www.awea.org, & the U.S. Department of Energy Wind Energy Program


US annual growthg

Source: www.ucsusa.org


g

Recent US annual growthg

Source: www.awea.org


USA – 2006Cumulative wind turbine capacity in the USA, end of 2006 [MW]:

Source: www.awea.org & the U.S. Department of Energy Wind Energy Program


USA – 2008



USA – 2009



USA – 2010Source: www.awea.org


Global Market Development

Mostly China and India

Mostly Brazil

Source: www.ewea.orgg


Global Manufacturers’ Overview

Major prod cers of

(Now “Alstom Power - Wind division”)

Major producers of wind turbines & their market shares in 2002. This status-quo was

(Taken over by Gamesa)This status-quo was almost same in 2005.

By 2010, Suzlon has d d l t dexpanded a lot, and

new names have entered the market. (Now “Siemens”)

(Now “GE Wind Energy”) (Now joined with Vestas)


(Now GE Wind Energy ) (Now joined with Vestas)

Wind Lecture -1- History&Targets

Documents

production

wind power

power output

annual growth

wind power

green certificates

rated capacity

energy technology