Tapping volcanos for geothermal power

Costa Rica and geothermal power make obvious sense – the country is teeming with geological activity, a fact apparent to anyone who has visited active volcanoes like Arenal or Poás.

Now there’s an effort to turn more of that underground heat into electricity, with the building of three new geothermal power plants. The plants’ prospects got a big lift this week when Costa Rica and Japan signed an agreement under which the Japan International Cooperation Agency will provide $560 million in loans for the projects.

Volcanic activity like that at Arenal shows Costa Rica’s geothermal potential. (image viaWikipedia)

The three plants would be able to produce a total of 165 megawatts of power, and of course as geothermal, that’s power that flows around the clock, not just when the wind blows or the sun shines. This would be a huge boost in Costa Rica’s geothermal capacity, which right now stands at 166 MW and provides about 12 percent of the country’s electricity.

“This is clean, renewable and reliable energy, as reliable as any conventional thermal electrical power plant,” Teofilo de la Torre, executive president of the Costa Rican Electricity Institute, told the Tico Times.

Costa Rica has an ambitious goal to source nearly all its energy from clean sources. According to a report earlier this year from the Geothermal Energy Association [PDF], it has been a bit slow to seize upon its vast potential because “a lot of its resource is wthin the boundaries of national parks.”

There has been debate about opening up Ricon de La Vieja National Park for some geothermal development, but none of the three proposed plant sites – for the 55-MW Pailas II, which is to be beuilt first, and Borinquen I and II, each 50 MW in capacity – is in the park.

The 30-year loan deal carries an interest rate of 0.6 percent and has a grace period of 10 years.

* Pete Danko, EarthTechling