The Use of Geothermal Energy in Europe
Today, geothermal power plants exist on every continent, at any place where reservoirs of steam or hot water can be found. There are, with conventional technology, around 1,000 MW of electric power installed in the EU, around the clock. In some regions of Europe, geothermal power plants already substantially contribute to an environmentally friendly and sustainable energy source, using existing technologies of exploiting steam and hot water reservoirs. This is, for example, the case of Italy, the Azores, and other islands of volcanic origin in Europe including, last but not least, Iceland4 and Turkey, among others. In Southeast Europe, Turkey, and the Caucasian region, reservoirs may contribute to a sustainable energy supply. The status of geothermal power production is presented in Table 6.1.
Among the initiatives dedicated especially to the promotion of wider geother- mal development for hearing within the EU, one should mention “The Kistelek Declaration” adopted in 2005. It points out good geothermal resources in many regions, which can provide a considerable share in the heating sector. The declaration indicates that to achieve such a goal the EU shall foster its member states to adopt a coherent legislation and economic system to ease geothermal use. Following the Kistelek Declaration, an EU-funded project GTR–H (Geothermal Regulation—Heat) is being carried out. It aims to propose the legal framework that would facilitate the development of the geothermal heating sector. In the European countries, geothermal research, research and development, and investment projects can be supported by the public sources (national budget or specialized funds) devoted for the sector of renewables, environmental protection, infrastructure, etc. Some countries like France and Germany have special guarantee funds to limit the risks connected with drilling the first geothermal wells or limit the results of worsening exploitation parameters with time. Support comes also from the EU budget in the form of various funds and programs oriented at renewable energy sources and other sectors (Ke˛pin´ska 2008).
Undoubtedly, geothermal energy is an ecological and efficient type of energy sources for the generation of electricity and an important source for the reduction of energy costs. In addition, geothermal energy, according to the European Renewable Energy Council:
1. Is a renewable energy source:
• An energy resource nearly infinite, delivering heat and power 24 h a day throughout the year, and available all over the world;
• A secure energy supply by making use of the immense internal heat of the
earth, and of the large thermal storage capacity of the ground;
• Friendly for the environment: contribution to the reduction of CO2;
• Very low visual impact—most of the infrastructure can be hidden beneath
the ground.
2. Is a safe and controlled technology:
• Not depending on climatic conditions;
• Proven and controlled technically: design and drillings;
• Defined components (power plants, district heating, and heat pumps);
• Excellent feedback from leading countries.
3. Is energy adaptable with high performance:
• An answer to different energy needs: electric power, heating, cooling, and hot water;
• Modulated according to type of resource, to the size and nature of equipment’s,
and in order to meet demand;
• For the heating sector: Adaptable to old or new buildings, large or small, individual or district heating.
4. An economically sustainable energy:
• Large reduction of energy invoice;
• Long-term durability of installations;
• Not sensitive to conventional energy prices—the Earth will not send an invoice.
There are many advantages in the use of geothermal energy source for the generation of electricity. It can be extracted without burning a fossil fuel such as coal, gas, or oil; in other words, geothermal power plants do not have to use an intermediate technology to produce steam to power the turbine generators. Once you have built a geothermal power plant, the energy is almost free. It may need a little energy to run a pump, but this can be taken from the energy being generated. The land needed for geothermal power plants is smaller per megawatt than for almost any other type of power plant. Geothermal fields produce only about one-sixth of the carbon dioxide that a relatively clean natural-gas-fueled power plant produces. Binary plants release essentially no emissions. Unlike solar and wind energy, geothermal energy is always available, 365 days a year, and additional units can be installed as necessary. It is also relatively inexpensive; savings from direct use can be as much as 80 % over fossil fuels.
But it has some environmental problems. The main concern is the release of hydrogen sulfide, a gas that smells like rotten egg at low concentrations. Another concern is the disposal of some geothermal fluids, which may contain low levels of toxic materials. Although geothermal sites are capable of providing heat for many decades, eventually specific locations may cool down. Geothermal energy can only be used in areas where the Earth’s crust is thin and the steam or hot water sources are close to the surface.
Summing up the following can be stated:
• Geothermal energy has been around since the Earth formed, and humans have used hot springs heated by geothermal activity for thousands of years;
• The process of extracting geothermal energy has been in existence for over a hundred years. Electricity from this energy source was first generated in 1903 in Italy;
• Geothermal power is seen as clean, efficient, and cost-effective yet can only be produced in particular areas;
• Iceland has the world’s most efficient geothermal power plants and contributes a
large percentage of global geothermal electricity production levels;
• The placement of geothermal power plants is very difficult as they have to be placed in an area of high geological activity to be highly efficient;
• Geothermal energy is greater along fault lines in the Earth’s crust, and volcanic
regions as liquid rock (magma) can be found closer to the Earth’s surface, thus providing more geothermal heat;
• Geothermal energy can also be used to provide heating for homes. This technique makes use of ground-source heat instead of the geothermal energy described above.