Wind farms could supply planet’s power

Telegraph

Tuesday, June 23, 2009

Even operating at just a fifth of their full capacity, a global network of 2.5 megawatt wind turbines sited away from urban centres would easily meet global electricity demands, a study suggests.

Currently only a fraction of energy is supplied by wind power, even in the UK which is considered the windiest country in Europe.

In 2007 wind energy overtook hydropower to become Britain’s largest renewable generation source. However, it still only contributed 2.2 per cent of the UK’s electricity supply.

The Government has set a target of meeting 15 per cent of all the UK’s energy demands from renewables by 2020, which means between 35 per cent to 45 per cent of electricity will have to come from green sources. Most of this is expected to be generated by wind farms.

For the new study, a team of international scientists led by Professor Michael McElroy at Harvard University in the US, divided the world into areas of around 3,300 square kilometres.

They then identified regions that would be suitable for wind farms.

The scientists worked out the potential for wind power electricity generation based on wind speed, air density, the spacing of turbines, and the size of turbine blades.

The findings are published in the journal Proceedings of the National Academy of Sciences.

The researchers concluded: “The analysis suggests that a network of land-based 2.5 megawatt turbines operating at as little as 20 per cent of rated capacity, confined to non-forested, ice-free regions would be more than sufficient to account for total current and anticipated future global demand for electricity.

“The potential for the contiguous US could amount to more than 16 times current consumption. Important additional sources of electricity could be obtained by deploying wind farms in near-shore shallow water environments.”

Nick Rau, of Friends of the Earth, said: “This is further evidence of the huge role that wind power can play in cutting climate-changing emissions and meeting our energy requirements.

“The report also highlights the UK’s huge wind power potential, one of largest in the world, and suggests it could easily supply our electricity needs many times over.

“The Government must reap the economic and environmental rewards from developing green energy by urgently tackling the barriers that prevent wind energy from taking off, and make this country a world leader in developing a clean and prosperous low-carbon economy.”

Denmark to power electric cars by wind in vehicle-to-grid experiment

UK Guardian
Duncan Graham-Rowe
Friday, June 19, 2009

Cars could be the solution to the intermittent nature of wind power if a multimillion European project beginning on a Danish island proves successful.

The project on the holiday island of Bornholm will use the batteries of parked electric cars to store excess energy when the wind blows hard, and then feed electricity back into the grid when the weather is calm.

The concept, known as vehicle-to-grid (V2G) is widely cited among greens as a key step towards a low-carbon future, but has never been demonstrated. Now, the 40,000 inhabitants of Bornholm are being recruited into the experiment. Denmark is already a world leader in wind energy and has schemes to replace 10% of all its vehicles with electric cars, but the goal on the island is to replace all petrol cars.

Currently 20% of the island’s electricity comes from wind, even though it has enough turbines installed to meet 40% of its needs. The reason it cannot use the entire capacity is the intermittency of the wind: many turbines are needed to harness sufficient power in breezes, but when gales blow the grid would overload, so some turbines are disconnected.

So the aim of the awkwardly named Electric Vehicles in a Distributed and Integrated Market using Sustainable Energy and Open Networks Project – Edison for short – is to use V2G to allow more turbines to be built and provide up to 50% of the island’s supply without making the grid crash.

Each electric vehicle will have battery capacity reserved to store wind power for the island rather than for travelling. This means it acts like a buffer, says Dieter Gantenbein, a researcher at IBM’s Zurich Research Laboratory. IBM is developing the software needed for the island’s smart grid, and will showcase its work next week. When the cars are plugged in and charging their batteries, they will absorb any additional load the grid cannot cope with and then feed it back to power homes when needed, he says.

“It’s never been tried at this scale,” says Hermione Crease of Cambridge-based Sentec, which develops smart grid software. There are plenty of smart grid trials already under way, usually involving the use of software to monitor and manage supply and demand, for example, by temporarily switching off industrial cooling units during periods of peak load, she says. But unlike these so-called “negawatt” approaches, proving that cars can be used as part of the grid has yet to attempted.

Andrew Howe of RLTec in London, another smart grid technology firm, says many important questions need answers. It is not clear, for example, how the cost and lifetime of batteries will influence the economics of such a system.

These are the kinds of issue the project seeks to shed light on, says the project manager Jørgen Christensen of the Danish Energy Association, which with technology companies Siemens and Dong and the government are running the scheme.

China to Invest $14.6 Billion in Wind Power by 2010

Bloomberg News
John Liu
Tuesday, June 2, 2009

China, the world’s second-biggest energy consumer, will invest about 100 billion yuan ($14.6 billion) to more than double its wind power capacity by 2010 from last year, a government official said.

The country’s wind power capacity will rise to 30,000 megawatts from 12,000 megawatts, Shi Lishan, deputy director of renewable energy at the National Energy Administration, said in Rudong city in the eastern province of Jiangsu today. China’s wind power capacity was the fourth-largest in the world last year, according to Shi.

Investment in alternative energy may exceed 2 trillion yuan by 2020, the National Development and Reform Commission, China’s top economic planner, said in 2007. Wind power is “vital” as it is the cheapest form of renewable energy, Shi said. About 80 percent of the country’s power is produced from coal.

“The on-grid price for wind power is about 0.5 to 0.6 yuan per kilowatt-hour compared with about 0.2 to 0.4 yuan per kilowatt-hour for coal,” Shi told reporters.

China Longyuan Electric Power Group, which accounts for about a quarter of the nation’s wind-power capacity, plans to boost capacity to 6,000 megawatts by next year and to 20,000 megawatts by 2020, Vice President Huang Qun told reporters.

Longyuan, the renewable-energy unit of China Guodian Corp., one of the country’s five state power producers, was capable of generating 2,630 megawatts of electricity using wind turbines last year, he said.

Huang was accompanying a delegation of media, industry and government representatives on a tour of the 100-megawatt Rudong wind farm operated by Longyuan.

Government Spending

The government has allocated 210 billion yuan for energy- saving and carbon-reduction projects under its 4 trillion-yuan economic stimulus package, the planning commission said in May.

China is separately drafting a long-term plan to develop renewable energy to replace coal and oil with cleaner-burning fuels. Details will be released “soon,” Han Wenke, head of energy research at the commission, said last month.

The stimulus plan will accelerate the upgrading of power grids, Shi said today. There will be no new preferential policies for wind power projects, he said.

The Asian nation became the world’s biggest emitter of greenhouse gases from burning fossil fuels in 2006, followed by the U.S., Russia, India and Japan, according to U.S. Department of Energy data on Bloomberg.

Private Investment

China Resources Power Holdings Co., the third-biggest Hong Kong-listed mainland electricity supplier by market value, said today it received government approval for two wind projects in Gansu and Guangdong provinces totaling 221 megawatts in capacity.

It will cost about 8,000 yuan to add 1 kilowatt of wind capacity in China, about 30 to 50 percent less expensive than in Europe, Shi said.

“It normally takes 10 years for local developers to see returns on their investments in wind farms,” Chen Tao, an adviser at China Energy Conservation Wind Power Investment Co., said by mobile phone from Beijing.

The world’s third-largest economy will increase its wind power capacity by fivefold to 100,000 megawatts by 2020 from at least 20,000 megawatts next year to help fight climate change, Zhang Guobao, director of the energy administration, said May 26.

About five megawatts is sufficient to power about 1,000 households in China on average, Hu Zhaoguang, vice president of the State Power Economic Research Institute, said by telephone from Beijing today.

China could pass Europe, Japan and the U.S. to become the world’s biggest renewable energy consumer by 2010, Washington- based researcher WorldWatch Institute said in November 2007.