Geothermal heat

One of the countries that makes extensive use of direct geothermal heat is Iceland. This might seem surprising for a country with ice as part of its name. 

Another potential problem, particularly if geothermal water is not returned to its source, is land subsidence. For example, there has been significant subsidence at the Wanaker field in New Zealand. Finally, an annoying difficulty with geothermal heat has been the noise produced by escaping steam and water. The shriek of the high-pressure fluids is intolerable, and is usually dissipated in towers in which the fluids are... 

Before global warming the geothermal heat flow was the only net heat source on Earth. Since then heat dissipation from the global use of nonrenewable energy has resulted in an additional net heat source. 

A continental warming means that the underground is also warming up, which eventually will show by a reduced geothermal heat flow as the geothermal gradient decreases (Chapman, 1998). 

The goal of a design of a geothermal heat exchanger is to maintain a specified bandwidth of temperatures in the ground loop heat exchanger at... 

Henry H.R. and Kahout, F.A., Circulation patterns of saline groundwater affected by geothermal heating as related to waste disposal, in Symposium on Underground Waste Management and Environmental Implications, Houston, TX, Cook, T.D., Ed., American Association of Petroleum Geologists, 18, 1973,... 

The shallow geothermal heat used in the GSHPs came from the groundwater (14°C), which has different GHG emissions from the borehole or U-tube-based HPs [19, 32]. Besides, the... 

Self S.J., Reddy B.V., Rosen M.A. (2013). Geothermal heat pump systems status review and comparison with other heating options. Applied Energy, 101, 341-348. 

Geothermal electricity The geothermal heat derived from the hot underground environment is used to generate electricity or may be used to supply heat for hot water and for heating buildings. 

Solid Oxide Electrolysers (SOE) are in development for steam electrolysis. As electrolysis is an endothermic process, a supply of waste heat can be used beneficially to reduce the electrolyzer voltage, and thus increase its electrical efficiency. Combination with nuclear power generation and geothermal heat sources is often encountered in development programs for SOE. 

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