Environmental aspects of geothermal energy
Any type of energy production will have some impact on the environment, but the degree or extent of this impact will depend on the technology used. Disguising or even concealing of environmental effects is penalizing and can bring whole industry branches into discredit, through loss of confidence of authorities, financial circles as well as of the public (example: nuclear industry). Although geothermal energy is generally praised as being environmentally friendly, the environmental aspects of geothermal development are receiving increasing attention with the shift
in attitudes towards the world’s natural resources. Not only is there greater awareness of the effect of geothermal development on the surrounding ecosystems and landscape, but there is also a growing appreciation of the need for efficient and wise use of all natural resources. Protection of the environment is one of our most important obligations, whose goals were defined during the United Nations Summits in Rio (1992), Kyoto (1997) and Johannisburg (2002). Both of the principal geothermal applications (power generation, direct use) can have certain environmental effects. These need to be identified, quantified and, if necessary, reduced/minimized, at the very
least in order to comply with environmental regulation. Clear energy and environmental policies and regulations are of paramount importance for the development of renewable energy sources. The institutional framework, legislation and legal constraints are borderlines to delimit development, especially in view of environmental protection.
Within these limits there should be unequivocal administration of law. Besides the environmental effect on ecosystems also the social implications need to be considered. Whereas geothermal development can bring about local benefits (e.g. jobs, community taxes) there is potential for negative socio-economic consequences (e.g. increase of traffic), which needs to be clearly communicated towards those who could be involved. Local acceptance can become crucial for the acceptance of a development project. In order to cover the mentioned issues and implications, first the possible environmental effects are briefly described and subsequently the legal, institutional and social aspects.
Environmental issues
Geothermal energy utilization generally has a well-deserved image of an environmentally friendly energy source when compared with fossil fuels and nuclear energy; a comparison with other technologies clearly proves this. Nevertheless, both of the main geothermal applications, power generation and direct use, can have certain effects, which will be described and discussed in detail below. Mitigation/remediation measures will also be identified. Power generations will be treated first. For all kinds of the technology used for geothermal energy utilization (which mainly depend on the subsurface conditions and the properties of the fluids produced) the main phases of development are basically the same:
• exploration (incl. some drilling);
• production drilling and testing;
• construction of surface facilities;
• operation.
Of these, only the operation phase is accompanied by incessant effects. The environmental effects of these phases may be temporary or lasting, reversible or irreversible and include
• changes to natural features, landscape, land use;
• noise;
• emissions into the atmosphere, surface and subsurface waters;
• land subsidence, seismicity;
• waste heat and solid waste.
Reference :
Rybach, L. (2003): Geothermal energy: sustainability and the environment. Geothermics
Tags: clear energy, Environmental aspects, environmental issues, environmental policies, environmental protection, geothermal applications, Geothermal Energy, type of energy production