Off-Shore Wind Power Set to Expand

In South Korea, wind power would be a likely resource to help the world's tenth largest energy consumer meet government goals to lower fossil fuel dependency through greater investment in renewable energy.

In South Korea, wind power would be a likely resource to help the world's tenth largest energy consumer meet government goals to lower fossil fuel dependency through greater investment in renewable energy.

Yet efforts to build wind turbines in South Korea have met fierce opposition, even among environmentalists, due to the lack of open land in the densely populated country. Only about 100 megawatts (MW) of wind power are installed nationwide despite plentiful wind resources and government price controls that keep renewable power competitive with traditional energy sources.

The solution might be found off the Korean peninsula's shores, and South Korea is not alone. As more countries seek to increase their renewable energy ratios, many consider off-shore wind a potential solution to provide clean energy without affecting local landscapes and communities.

Off-shore wind has so far taken a back seat to on-shore wind farms during the current boom in wind energy development. Off-shore turbines are more difficult to maintain, and they cost $.08-$0.12 per kilowatt-hour, compared to $.05-$.08 for on-shore wind.

But off-shore wind farms offer several benefits over their land-based counterparts. Strong ocean winds allow one off-shore turbine to generate substantially more power than one on-shore turbine. Also, if an off-shore wind farm is located near a coastal city, clean energy would be available without dedicating land to new transmission lines.

Denmark installed the first off-shore wind farm in 1991. Since then, slightly more than 1 gigawatt  (GW) has been installed worldwide, mostly in the North Sea, according to the European Wind Energy Association (EWEA). An additional 3.8 GW is expected in the next four years, forecasts British energy firm Douglas-Westwood, Ltd. Based on their estimates, annual installations are set to increase from 419 MW in 2008 to 1,238 MW in 2012, with the United Kingdom, Belgium, Denmark, Germany, and China leading the way.

In Europe, about 80 percent of the off-shore wind market will be concentrated in Denmark and the United Kingdom by the end of this year, with 1 GW planned by the two countries combined, EWEA said in a policy recommendation report. The association predicts that 50 GW of off-shore wind will be operating in Europe by 2020.

In Asia, China installed its first off-shore wind farm in November. The country plans to add more than 1.5 GW of off-shore projects. Feasibility studies are under way in South Korea and Japan.

Along North America's coasts, a handful of projects are moving forward, and several more are tied down in local site disputes. According to a U.S. Department of Energy report, more than 900 GW of off-shore wind power could potentially be tapped from U.S. shores, mostly along the northeastern and southeastern seaboards. The United States is expected to finalize its leasing rules for off-shore wind farms this year.

Similar to concerns that on-shore wind farms threaten bat and bird populations, off-shore wind farms could disrupt marine ecosystems. The initial construction may kill organisms on the seafloor, and transmission cables create magnetic and electric fields that may disrupt fish orientation.

But researchers are still unsure what damage might occur, and several studies suggest that turbine construction and operation would pose minimal threats. Some experts suggest the turbines would benefit marine life by creating artificial reefs.

Weather may also be a limiting factor. Harsh winds often prevent construction during winter months, slowing development. Turbines are designed to sustain winds as strong as 200 miles per hour, but so far few have experienced intense hurricanes. 

Ben Block is a staff writer with the Worldwatch Institute. He can be contacted at This email address is being protected from spambots. You need JavaScript enabled to view it..