Power Plant Engineering

NON-CONVENTIONAL ENERGY RESOURCES AND UTILISATION 95

turbine to 10. The condensate at 11 is pumped and reinjected into ground at 12. The spent brine from
the second stage evaporator is also reinjected in to ground at 16.

Regenerator Fossil-firedsuperheater High-pressure

turbine Low-pressureturbine

10

Condenser

11

12

Reinjection

16

Ground

Well

1

13

2

3 13

14

15

(^48)
5
6
7
9
9
Separators
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.