Power Plant Engineering

 Fig. 2.38. Schematic of a fossil-superheat hybrid system with two-stage flash evaporation, regenerator,
and fossil-fired super heater.
Fig. 2.39. Crops surround this plant in Imperial Valley, Calif. High mineral contents of some southern
California geothermal reservoirs provide salable by-products like silica and zinc.
2.20.5 ADVANCED CONCEPTS
Geothermal energy technologies use the heat of the earth for direct-use applications, geothermal
heat pumps, and electrical power production. Research in all areas of geothermal development is help-
ing to lower costs and expand its use.
Advanced technologies will help manage geothermal resources for maximum power produc-
tion, improve plant-operating efficiencies, and develop new resources such as hot dry rock, geopressured
brines, and magma.
Encouraged by the findings of nearly 340 hot springs in the country, a systematic collaborative,
research, development and demonstration programme was undertaken with different organizations viz.

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POWER PLANT ENGINEERING
IIT, Delhi, National Aeronautic Limited, Bangalore, Geological Survey of India, National Geophysical
Research Institute (NGRI), Hyderabad, Oil & Natural Gas Corporation etc. and the use of geothermal
energy was demonstrated in the country for small scale power generation and thermal applications.
After ascertaining the existence of potential reservoirs in Tattpani and Puga geothermal fields in
Chhattisgarh and Jammu & Kashmir respectively through Magneto-telluric investigations by NGRI,
Hydrabad, the Ministry is planning to develop these fields for power generation. Sutluj-Spiti, Bcas and
Parbati valley in Himachal Pradesh, Badrinath-Tapovan in Uttranchal and Surajkund in Jharkhand also
have some potenital sites for power generation. A programme for ascertaining the existence and poten-
tial of the reservoir at these sites is being planned by the Ministry through NGRI, Hyderabad and
NHPC. As most of the geothermal sites in the country are in low and moderate temperature range,
some demonstration projects with direct heat utilization are being planned to be taken up at different
places in the country. About 1400-3600 Mwe plants are under operation/under construction. World
wide non-electric applications amounts to 6000 MWt. boils and turns into steam. Since this steam is
trapped between rocks, its pressure increases. Identifying such places and inserting pipes there to bring
out the steam to drive a turbine, electricity can be produced.