Technology Status - NET Nowak Energie & Technologie AG

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geothermal power with respect to total electric power installed is 10% or
more in the Philippines, El Salvador and Nicaragua.
● Environment
Table 40 summarises the probability and relative severity of the effects on
the environment of geothermal direct-use projects.
Table 40
Probability and Potential Severity of Environmental Impact of
Geothermal Direct-Use Projects
Impact Probability Severity
Air quality pollution L M
Surface water pollution M M
Underground pollution L M
Land subsidence L L-M
High noise levels H H-M
Well blowouts
Conflicts with cultural and
L L-M
archaeological features L-M M-H
Social-economic problems L L
Chemical or thermal pollution L M-H
Solid waste disposal M M-H
Source: Lunis and Breckenridge.
L = Low; M = Moderate; H = High.
Environmental concerns related to geothermal energy use include:
Pollutants: Geothermal energy produces non-condensable gaseous
pollutants, mainly carbon dioxide, hydrogen sulphide, sulphur dioxide and
methane. Carbon dioxide is a natural compound present in the fluids used in
geothermal power plants. However, the level of CO2 discharge from these
plants is much lower than from fossil-fuelled power stations. The condensed
geothermal fluid also contains dissolved silica, heavy metals, sodium and
potassium chlorides, and, sometimes, carbonates; but, modern emission
controls and re-injection techniques have reduced these impacts to a
minimum. Geothermal energy has a net positive impact on the environment
because it pollutes less than conventional energy.
GEOTHERMAL POWER X6