-------------------------------------Geothermal energy

as an electricity source in the region of Slovakia

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Beladice, 2011

Geophysical institute of SAS

the mean temperature gradient at the Earth’s surface is about 30˚ C per 1 km(up to 100 ˚ C in the depth of 3 km and about 300 ˚ C in the depth level of 10 km)

the geothermal sources for classical production of electricity are accessible at the depth level 10 -12 km

usual depths of bore holes are up to 3 - 5 km; deeper (>10 km) ones are now exceptional

geothermal capacity of the Earth: all consumption of energy (past and future) should cause decrease of the mean temperature of the Earth only one degree in 40 milion years.....

1 - hydro-geological source 2 - “hot dry rock” source

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Classification of geothermal sources according the utilization potential

In 1904 emerging steam was used to turn a small turbine which powered five light bulbs - the first ever demonstration of geothermal electricity generation. (Larderello, Italy) - - - - - - - - - - - - - - - - - - >

The world's first geothermal power station was

built in 1911 in Larderello, in Southern Tuscany, Italy and later …

< - - - - - - - - - - - - - - - - - - - - -

(in 1913) a 250kW power station had been built which provided power for the Italian electric

railway system.

Typical production of electric power

Husavik, nordth Island; 2MW – 80 percent of town electricity consumption (~2000 inhabitants)

120 ˚C – 80 ˚C; 90 kg/s; Kalina cycle technology

Kalina cycle – process diagram, Husavik

Production well

Reinjection well

Pump

Regenerator

Turbine

Warming-up

Separator

Binary cycle application regions in Slovakia(minimal required depth distributions)

Classic cycle application regions in Slovakia(minimal required depth distributions)