- [Voiceover] We know that the interior of the earth is hotter, we know that there is energy released from the reactions that are happening in the interior of the earth, this energy is transferred towards the surface of the earth and that's the kind of energy that we are taking advantage of in geothermal energy power. The thermal value of the earth, the average value is between 25 and Celsius degrees per kilometer however there are areas of the earth that have a higher geothermal gradient and higher heat flow, usually those areas are located at subduction zones, rift basins and hot spots. Obviously there are systems that have been exploited where the hydrothermal systems where the shallow heat causes thermal fluid convection. These hot hydrothermal fluids can be extracted from the earth and can produce electrical energy and that's the kind of plants that we can see all over the world. It is clear that in areas where we have hot springs those were and fumaroles those were the very first targets for the thermal exploitation. However, things have changed through the years and nowadays we have other systems that we are targeting and that seem very very promising and that can solve a lot of our energy problems. If we look at the history of geothermal energy we can see that the very first place where geothermal energy was exploited was in Larderello, Italy, they have there a dry steam field and the very first production of electrical energy from these fields was on July 4th 1904, in other words more than 100 years ago, the electricity that they produced was able to power only five light bulbs however later developments were that they were able to install a powerplant, the very first powerplant that produced 250 kilowatts of energy and since then Italy has been one of the places in the world where we have a great exploitation of geothermal energy. You can see geothermal energy production in Italy is really one of the greatest. However since that time geothermal energy exploitation has spread all around the world and right now we have more than 20 countries that are exploiting geothermal energy. This is, I tried to represent the 100% of the geothermal expected and collected geothermal energy around the world and we can see that the United States is the country that produce more, the greatest fraction of geothermal energy in the world, with almost 30% of the energy, Philippines is second and then Mexico and we have any other countries that are also producing geothermal energy but one thing that really is important to notice is that many of this is more countries like Costa Rica, El Salvador, the fraction of the electrical energy that they are generating from geothermal resources it can be up to 25% of the total energy, electrical energy of these countries. So geothermal energies have been really a great resource to reduce the consumption of oil and oil fossil fuels with the generation of geothermal energies in those countries.