Hot dry rock geothermal energy as a separate state from that of the continuum of permeable rock—just as one would consider a completely closed faucet as distinct from one that is open to any degree, whether the flow be a trickle or a flood. In the same way, HDR technology should be regarded as totally distinct from EGS. A definitive book on HDR development, including a full account of the experiments at Fenton Hill, was published by Springer-Verlag in April 2012. Hot dry rock geothermal energy Hot dry rock (HDR) is an abundant source of geothermal energy available for use. A vast store of thermal
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