{"id":388,"date":"2019-03-29T08:26:30","date_gmt":"2019-03-29T08:26:30","guid":{"rendered":"https:\/\/www.tce.co.in\/blogs\/?p=388"},"modified":"2021-09-28T11:22:09","modified_gmt":"2021-09-28T11:22:09","slug":"geothermal-power-generation","status":"publish","type":"post","link":"https:\/\/www.tataconsultingengineers.com\/blogs\/geothermal-power-generation\/","title":{"rendered":"Geothermal Power Generation"},"content":{"rendered":"

Geothermal uses energy from the everlasting heat content present in the Earth\u2019s crust to
\ngenerate electric power and makes it sustainable energy source. The gas emissions released
\nby this power is only a fraction of that of coal fired thermal power plants and makes it
\nenvironment friendly. Unlike other renewable energy sources, geothermal depends on
\neverlasting heat content thus making it possible to achieve higher levels of capacity factor.
\nHowever, geothermal power plants operate at lower efficiencies of about 7-10% compared to
\nthermal power plants due to lower thermodynamic properties of the steam.<\/p>\n

Heat energy inside the Earth is in the form of high pressure hot liquid. This comes to the surface
\nnaturally either through hot springs or thermal circulation. If it does not come to the surface on
\nits own, wells need to be drilled into hot aquifer. In order to get the required fluid temperature
\nsometimes wells need to be drilled to deeper levels of several kilometres. Applying the
\npressure by means of gas\/ water, through boreholes on the surface of the hot fluid present in
\nthe earth, hot fluid production can be increased.<\/p>\n

Although quantitatively geo thermal potential would be less compared to others, Indonesia &
\nPhilippines in SE Asia and Kenya, Ethiopia, Rwanda in Africa have good geo thermal potential
\nand could see growth in this area in future. Currently Kenya has well established global
\ngeothermal presence with an installed capacity of about 630 MW and contributing more than
\n50% of electricity to the national electricity mix, and it also has plans to generate 3300 MW by
\n2033.<\/p>\n

Geothermal power can be generated in three different ways viz., using dry steam, flash steam and binary fluid. To achieve dry steam, its temperature requirement at the turbine inlet will be\"geo-thermal-pic\"<\/a> about 150\u00b0C hence this is not a commonly practice. The preferred method of power generation is by utilising the high pressure hot water from the earth\u2019s crust and obtains flashed steam by to operate the steam turbine. The flashed steam temperature is about 180\u00b0C. The latest practice is to use binary cycle power stations which can even operate with low fluid temperatures of about 60\u00b0C.<\/p>\n

The geothermal power project viability depends on several factors viz., nature of geothermal
\nfluid, extent of yield, depth of the source, reservoir temperature, steam parameters, plant
\nefficiency and cost of steam generation.<\/p>\n

The key phases of a geothermal project are:<\/p>\n