Geothermal energy is a little-known renewable source of energy. Some of the heat which occurs due to geological activities sometimes reaches the surface (for instance by thermal springs) in a depth of 20m to 2.000m, which means that it can be viably exploited.

In certain areas, where the groundwaters or steam is below of 150^oC, they can be used in agricultural applications (greenhouses, drying of wood and agricultural products etc.). In areas where the groundwater/steam is over 150^oC, the geothermal energy can be used to produce electricity. Although the source of energy in this case is renewable, it has a polluting effects to the local environment. Through the procedure of creating electricity, great quantities of salt are accumulated and hydrogen sulfide gas, between others, is emitted, and should either be removed from the area, or be neutralized.

A successful case of Geothermal Power Plant is Landerelloin Pisa, Italy. This plant produces 10% of the world's entire supply of geothermal electricity, amounting to 4,800 GWh per year and powering about a million Italian households!

Greece is located in an area where many earthquakes take place and therefore sources of geothermal energy can be found in many different places. However, these sources are tenuously exploited. The most valuable sources of geothermal energy, which contain water/steam of high temperature (300^oC) are found on two small islands of the Aegean Sea, with great ecological value. These islands are Nisyros and Milos.

In Nisyros the sources are located in the caldera of the dormant volcano which exploaded about 40.000 years ago.

On the island of Milos, in 1986, a factory was built, producing 2MW of electricity. However, in 1988, a big explosion caused it to emit large quantities of hydrogen sulfide which polluted all the nearby area: plants, animals, air and sea. As a result, the factory was abandoned.

On the island Nisyros, while the first project of electricity production by geothermy was inaugurated, in 1981, the geothermic substance in a few minutes surpassed the pressure and temperature expected. During the following hour, 40,000L of sea water had to be injected into the installation and a great quantity of salts were accumulated.

While the state company of electricity has new plan since 2013 to make another geothermical factory, the local societies were reserved with the idea of geothermic factory and its effect on their islands, being aware of the previous accidents made.

- In my opinion, we should take advantage of this renewable form of energy. However, the cursoriness in which the factories were built allows local people to rationally disapprove this project.

- On the same moment, after what we have been taught from the conflict with the local society on the gold mines in Chalkidiki, I believe that such projects, which affect an island, with such a fragile nature, at this grade, shall request the agreement of local inhabitants.

- In order to achieve this agreement, apart from the compensation, the local society should request a research which will recognise the possible dangers and threats of this project and prevent them. Lastly, such an enterprise should respect the other economic fields of the island such as tourism, agriculture and fishery.