In its December 6 2008 “Technology Quarterly”, the Economist has a case study on the history of wind power and how far it’s come.
Technology deployment is never instantaneous. It takes time to improve the technology and it takes more time to deploy the technology.
As the authors say “The basic idea is ancient, but its modern incarnation adds many new high-tech twists”. Here are some highlights from the Economist article:
Improved technology and design
- Danish model with three-bladed horizontal-axis, upwind machine becomes broadly accepted in early 1980s, over vertical axis “egg beater” and two-blade horizontal axis models.
- Improved knowledge of impact of fluctuating winds (wind gusts) on turbine structure and gear boxes lead to variable pitch of blades, variable speeds and better control systems.
- Optimization of machines and weight reduction achieved through mathematical models – components become lighter, machines are scaled up.
- Move to larger “off-shore” ocean-based machines, e.g. 7.5MW. Total installed off-shore capacity expected to reach 8 GW by 2012.
- Efforts are ongoing to improve gear boxes, or eliminate them entirely with a “direct drive” system.
- At 50% efficiency – i.e. % of kinetic energy extracted from wind, today’s machines are coming close to maximum theoretical efficiency limit of 59%.
Increased capacity of wind machines
- In the 1980’s, after the first OPEC crisis, windfarms began sprouting in California, thanks to generous incentives.
- Rotor diameters were about 15 metres with production capacity in the tens of kilowatts.
- Today rotor diameters reach 100 meters, with capacity 30 to 50 times larger.
Lower Costs
Generating costs have dropped from 30 cents a kilowatt hour in the 1980s down to approximately 10 cents in 2007.
Exponential rate of technology deployment
In 2007, wind power produced 1% electricity globally, and is expected to reach 2.7% in 2012, and 6% by 2017.
In Europe, in 2007 wind contributed:
- 20% of Denmark’s electricity (the country has had an ambition R&D program since mid 1970s and is the world leader in the field),
- 10% for Spain, and
- 7% for Germany.
- In 2007, Germany accounted for almost one quarter (23.7%) of the world’s installed windpower; and
- the US was at 18%. By comparison, in the 1980s, California was the world leader and held 90% of the world’s installed wind capacity.
- China has been doubling its wind capacity every year since 2004.
Barriers to innovation and change
- Need for better transmission lines to integrate windpower into grid and capacity to absorb fluctuations
- Dependency on subsidies makes industry vulnerable to sudden cut-off (at least until some form of carbon tax is in place), e.g. abrupt halt of California’s industry when subsidies were cut in mid-1980s.
- NIMBY – resistance from consumers who don’t like the noise or cluttered horizon, and are worried about danger to birds.
These barriers are very siumilar to Margaret Wente's article last year (see our earlier Post)
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