China is now at the forefront of wind technology, and its capacity continues to grow by leaps and bounds. At the end of 2010, China surpassed the US to become the world leader in installed wind power capacity, with a total of 44.7 GW.
2010.8.10 Saihanba wind farm in Chifeng, Inner Mongolia with a total installed capacity of 120,700 kW and annual power generation capacity of 2.7514 billion kWh. ©Greenpeace/Simon Lim
China's rapid growth in wind energy has broken even its own targets. From 2006 to 2009, China's overall wind installation doubled in capacity each year. In 2009, it led the world in newly installed wind turbines – building 10,129 turbines (13.8 GW), at a rate of one per hour – and overtook Germany to become the world's second-largest wind installation country. In 2010, China became the world's largest wind installation country.
By 2020, China's total wind power capacity will reach at least 150GW, possibly up to 230GW. If realized, this could replace over 200 power plants and cut 410 million tons of CO2 emission, or 150 million tons of coal consumption.
How does it work?
Wind power, the world's fastest growing energy source, is a deceptively simple technology. Behind the tall, slender towers and steadily turning blades lies a complex interplay of lightweight materials, aerodynamic design and computer-controlled electronics.
Power is transferred from the rotor through a gearbox, sometimes operating at variable speed, and then to a generator (although some turbines avoid a gearbox by use of direct drive).
Two decades of technological progress have resulted in state-of-the-art wind turbines that are modular and rapid to install. Today, a single modern wind turbine is 100 times more powerful than its equivalent two decades ago, and now wind farms provide bulk power equivalent to conventional power stations.
As the market has grown, wind power has shown up to a 50% drop in production costs over the past 15 years. At optimum sites, wind can be competitive with new coal-fired plants and, in some locations, can challenge gas.
Challenges and Obstacles for China's Wind Development
While China may be a world's number one in installed wind capacity, it falls behind when it comes to actual electricity generation. As of 2009, it was behind the US, Germany and Spain in terms of total electricity generated from wind energy.
Many wind farms in China are idle, faced with several serious challenges. The biggest obstacle is the lack of grid access for wind farms. Grid-connected capacity lags behind installed capacity by more than 30%, much higher than the 10% gap in advanced countries.
The grid structure is also unstable and outdated: it needs a massive overhaul to effectively distribute the varying amounts of electricity from wind.
China passed a landmark renewable energy law in 2005 that requires grid companies to purchase all available renewable electricity. Unfortunately, this does not happen, due to a lack of incentives for grid companies to purchase renewables; conversely, if they fail to do so, there are no penalties either.
Wind power still accounts for only a tiny fraction of China's entire energy structure. The country must translate its massive installations to massive utilization, which requires the implementation of effective incentive policies and a thorough overhaul of the national grid.
Worldwide wind power today
Worldwide installed capacity reached 196.6 GW, of which 37.6 GW were added in 2010. Globally, all wind turbines installed by the end of 2010 can generate 430 terawatt-hours per year – more than the total electricity demand of the United Kingdom, the sixth largest economy of the world, equaling 2.5 % of global electricity consumption.
Europe led the world in the percentage of energy generated from wind, with Denmark (21%), Portugal (18%) and Spain (16%). Asia, primarily led by China, accounted for the world's largest share of new installations (54.6 %), followed by Europe (27%) and North America (16.7 %).
Wind power by 2020
With installed wind capacity growing at 30% over the past few years, it is an entirely realistic goal to for wind to provide 12% of the world’s energy by 2020. Along the way, this would create two million jobs, and save more than 10,700 million tonnes of carbon dioxide emissions.
Wind power beyond 2020
The world's wind resources are extremely large and well distributed across almost all regions and countries. Using current technology, wind power could supply an estimated 53,000 Terawatt hours (TWh) per year. This is more than twice the projected world energy demand in 2020 – leaving substantial room for growth in the industry even decades from now.
Advantages of wind
- Environmentally friendly: A reduction in the levels of carbon dioxide emissions is the most important environmental benefit from wind power generation. It is also free of the other of other pollutants associated with fossil fuel and nuclear plants.
- Extremely good energy balance: The carbon dioxide emissions related to the manufacture, installation and servicing over the average 20 year lifecycle of a wind turbine are "paid back" after the first three to six months of operation – which means more than 19 years of energy production at virtually no climate or energy cost.
- Quick to deploy: Construction of a wind farm can be completed within a matter of weeks, with large cranes installing the turbine towers, nacelles (housing) and blades on top of reinforced concrete foundations.
- Reliable and renewable resource: Wind to drive the turbines will always be free of charge, and unaffected by swings in the price of fossil fuels. It also doesn't need to be to be mined, drilled for or transported to the generating station. As world fossil fuel prices rise, so does the value of wind power, and its generating costs will only drop.
Furthermore, in larger projects, using proven medium-sized turbines, an operational availability of 98% is consistently achieved. This means that there's only a 2% down time for repairs – a far better performance record than what can be expected from a conventional power plant.
Variability of wind
The variability of wind has produced far fewer problems for electricity grid management than skeptics had anticipated. Swings in energy demand and the need to protect against failures of conventional plants actually require more flexibility of the grid system than wind power, and real world experience has shown that national power systems are up to the task. On windy nights, for example, wind turbines account for up to 50% of power generation in western Denmark, but the load has proved manageable.
The creation of super-grids also reduces the problem of wind variability by allowing changes in wind speed in different areas to be balanced against each other.
Moving forward
Despite its recent rapid growth, the future of wind power is not guaranteed. The prediction of 12% of the world's energy from wind power by 2020 should not be seen as a sure thing, but as a goal – one possible future we can choose if we are willing.
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