geothermal

Relating to or produced by the internal heat of the Earth, especially as a source of energy or as it manifests in hot springs, geysers, and volcanic activity.

• geothermally(adv)
• geothermic(adj)

• geothermal energy
• geothermal power
• geothermal heat
• geothermal springs
• geothermal activity

1. 1.Iceland generates over 25% of its electricity from geothermal power, tapping the volcanic heat beneath its surface. (earth-heat energy)
2. 2.New Zealand's Wairakei was one of the world's first geothermal power stations, harnessing the Taupo Volcanic Zone's heat since 1958. (renewable energy)

• volcanic— relating to volcanoes, narrower
• hydrothermal— relating to hot water from the earth

from Greek "geo" (earth) + "therme" (heat) — heat from the earth