Wave energy
Wave energy is already being used across the world. Billions of dollars have been invested in the technology and the world's first "wave farm" opened near Porto in Portugal in 2008. At the European Marine Energy Center in Orkney, Scotland, the world's biggest wave farm was approved for construction earlier this year. The 40MW farm off the north-west coast of Lewis promises to deliver enough energy to power nearly 30,000 homes.
Wave farms deploy massive buoys to turn the motion of waves into power. Aquamarine Power the company running the project in Orkney, says that its huge yellow buoys have "a maximum generating capacity of 800kW." The bright yellow machines measures 26 meters across and are installed at a depth of around 13 meters, around 500 meters from the shore.
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The advantages of wave power are similar to those of wind -- the waves are free -- but there are some additional benefits. In particular, it's easier to forecast wave energy output, because waves are driven by wind, but don't vary as rapidly; they build up more slowly and dissipate more gradually. That makes the energy from waves more predictable than that from wind or solar, which means that it is easier to integrate into the power grid.
At present the UK is the world leader in the technology, with the U.S., Portugal and France also significant players.
Source: CNN, Internet
