Geothermal energy in the United States Geothermal Data System (NGDS). Through the NGDS, many older paper archives and drill logs that are stored at state geological surveys are now being digitized and made available for free to the public. The underground hot water and steam used to generate geothermal power may contain chemicals that could pollute the air and water if released at the surface. Hydrogen sulfide, which is toxic in high concentrations, is sometimes found in geothermal systems. Newer methods of generating geothermal power separate the hot steam collected underground from the steam used to power turbines, and substantially reduce the risk of releasing air-polluting
Prospective Outlook on Long-term Energy Systems Prospective Outlook on Long-term Energy Systems Prospective Outlook on Long-term Energy Systems (POLES) is a world simulation model for the energy sector that runs on the Vensim software. It is a techno-economic model with endogenous projection of energy prices, a complete accounting of energy demand and supply of numerous energy vectors and associated technologies, and a carbon dioxide and other greenhouse gases emissions module. POLES was initially developed in the early 1990s in the Institute of Energy Policy and Economics IEPE (now EDDEN-CNRS) in Grenoble, France. It was conceived on the basis of research issues related to global energy supply