International Energy Agency data shows that wind power accounts for 4% of global energy production. It is in Northern Europe that wind turbines contribute most to energy supply but the latest technology in the world of giant wind turbines means that the market is growing quickly. Technology advances also mean production prices have fallen significantly in recent years to reach efficiency levels that mean government subsidies are no longer necessary. This has led to new markets opening up as wind power reaches grid parity in windier locations in the USA, Asia and beyond.
A recent New York Times article provides a fascinating insight into the technology being used to create turbines with blades that can now be as large as the wing of a jumbo jet, mounted on stretching 600 feet into the air. The larger the turbine, the lower the cost of producing electricity, despite the fact that these giants can cost as much as almost £9 million. However, the latest windmills now produce as 20 times more power than the early generations of the technology that appeared up to three decades ago.
The size of the modern blades on the biggest turbines means making them light enough to not put too much stress on other components or wearing down turbines quickly is a mighty feat of engineering. They can take up to 3 days to make by filling molds with interwoven layers of fiberglass and balsa wood injected with resins and hardening chemicals. Even so, the biggest still weigh up to 30 metric tonnes. The difficulty involved in repairing huge turbines, often placed out at sea, means they have to be durable. Components are built to last up to 20 years before they inevitably need to be replaced.
The technology employed to increase efficiency is impressive. Inspired by the wing feathers of owls, it has been found that adding a serrated edge to blades reduces sound as well as the strength of wind required to turn them.
The biggest wind power specialists, Siemens Gamesa Renewable Energy and Vestas Wind Systems, hail from Denmark, where the very first wind farms were built. Bonus, one of the first wind turbine companies, was founded in Jutland, northern Denmark in 1980 by Peter Sorensen. It still forms the backbone of Siemen’s wind power unit, which bought the company started with a couple of workers borrowed from Sorensen’s father’s irrigation company.
The technology used in the maintenance of giant offshore windfarms is also now very high tech. Carrying out repairs at sea is a complex operation but luckily specialists working at consoles in Denmark monitor windfarms around the world and can often shut down and restart problem turbines remotely without having to resort to sending expensive maintenance teams in.
As technology continues to bring down costs, wind power can be expected to see its contribution to global energy needs grow. Alongside the latest technology also improving solar and hydro efficiency, reliance on fossil fuels will hopefully continue to drop in coming years.