Hot dry rock geothermal energy Hot dry rock geothermal energy Hot dry rock (HDR) is an abundant source of geothermal energy available for use. A vast store of thermal energy is contained within hot - but essentially dry - impervious crystalline basement rocks found almost everywhere deep beneath the earth’s surface. A concept for the extraction of useful amounts of geothermal energy from HDR originated at the Los Alamos National Laboratory in 1970, and Laboratory researchers were awarded a U.S. patent covering it. Although often confused with the relatively limited hydrothermal resource already commercialized to a large extent, HDR geothermal energy is very different. Whereas
Hot Water Beach tide, it is possible to dig into the sand allowing hot water to escape to the surface forming a hot water pool. The water, with a temperature as hot as 64 °C (147 °F), filters up from two underground fissures located close to each other. These natural springs can be found on the beach opposite the off-shore rocks. Visitors often dig large holes and relax and soak in the thermal water. Many visitors bring a spade and bucket with them. Spades can also be hired from the nearby surf shop. Care needs to be exercised as the location of the