Tidal Power in South Korea
South Korea has devoted large resources to tidal power generation as it aims to become a leader in green energy technology. Under its national slogan of 'Green Growth', South Korea has committed to generating 8% of its energy from renewable resources by 2020. One of the projects that fell under the Green Growth program was the Sihwa Lake Tidal Power Plant.
Shiwa Lake Tidal Power Plant
Completed in 2011, the Sihwa Lake Tidal Power Station is the largest tidal power installation in the world at 254 MW (just edging out the Rance Tidal Power Station at 240 MW). The system is a tidal barrage scheme that makes use of an already-existing seawall that was built in 1994 for flood mitigation and agricultural irrigation. Unlike most barrage systems, power is generated during the influx of the tide rather than the outflow. This results in a slightly less efficient system, but is necessary to balance the land use/ water use, and environmental considerations of the barrage and surrounding area. Interestingly, the barrage has actually aided the environment.
By 2004, Sihwa Lake had become so polluted that its water was unusable for agricultural purposes. Pollution built up as a result of the lack of seawater influx that had been present prior to construction of the seawall. The idea to introduce seawater as a means of flushing the contamination led to the idea of a tidal barrage that could complement and make the seawater solution permanent.
Uldolmok Tidal Power Station
The Uldolmok Station is a tidal stream installation with a 1 MW capacity that was installed in 2009. There are plans to increase the array to 90 MW by 2013, generating enough power for about 46,000 South Korean families.
The array is built in the Uldolmok Strait, which is an area on the Southwest corner of the country that experiences tidal flows exceeding 6.5 meters per second (over 21 feet per second). Each turbine in the installation costs 10 million USD. No environmental studies have taken place or are planned for the Uldolmok Tidal Station, which is a loss not just to South Korea, but to the international community as well. Information from the pilot installation as well as the entire array could be invaluable for future tidal power plant construction.