ENERGY DEMOCRACY: Understanding our Alternatives?-?GEOTHERMAL ENERGY

Renewable energy technology is far from being totally exhausted. Every day we see new ways of tapping into Mother Nature to produce energy. So far, we have successfully explored many of these sources and have gone even further to develop them largely. Sadly not all these alternatives are being given the same attention. Of the many ‘Not so popular’ Renewable energy technologies, Geothermal Energy is one of them. First invented in 1904 by Prince Piero Ginori Conti at the Larderello dry steam field in Tuscany Italy, the geothermal technology has undergone different developments and has gone to contribute significantly to the growth of the Renewable Energy sector.

Geothermal Energy is simply the heat that comes from the sub-surface of the earth. It is contained in the rocks and fluids beneath the earth’s crust and can be found as far down to the earth’s hot molten rock, magma. Scientists have discovered that the temperature of the earth's inner core is about 10,800 degrees Fahrenheit (°F), which is as hot as the surface of the sun. Temperatures in the mantle range from about 392°F at the upper boundary with the earth's crust to approximately 7,230°F at the mantle-core boundary. Water and/or steam carry the geothermal energy to the Earth’s surface. Depending on its characteristics, geothermal energy can be used for heating and cooling purposes or be harnessed to generate clean electricity. However, for electricity generation, high or medium temperature resources are needed and they are usually located close to tectonically active regions.

Although the first effort to harness geothermal energy for industrial use came in 1818 in the Tuscan region of Italy where French engineer Fran?ois Jacques de Larderel pioneered a new way to extract boric acid from hot springs, it is postulated that Geothermal energy was one of the oldest types of power used by humans. Archaeological evidence suggests that the earliest direct use of geothermal power occurred at least 10,000 years ago in North America, where indigenous peoples were drawn to hot springs for both spiritual and practical reasons. Similarly, the peoples of ancient Greece and Rome viewed hot springs as places of healing imbued with sacred power and the Romans built shrines at hot springs, many of which yield archaeological evidence that people sought to communicate with the gods

To produce power from geothermal energy, wells are dug a mile deep into underground reservoirs to access the steam and hot water there. The hot water is pumped out of the deep subsoil and the heat is extracted using a heat exchanger and can be used for any purpose until it cools off. The cooled water is then pumped back and eventually heats up again because of the heat in the Earth. A geothermal installation therefore consists of at least two wells, one for the production of hot water, the production well, and one for the injection of cooled water, the injection well. The distance between these two wells in the deep subsoil is about 1 to 2 kilometres, and therefore they are partly drilled at an angle

Based on current geologic knowledge and technology, the Geothermal Energy Association (GEA) estimates that only 6.9 percent of total global potential has been tapped so far, while the IPCC reported geothermal power potential to be in the range of 35 GW to 2 TW. As of 2019, worldwide geothermal power capacity amounted to 15.4 gigawatts (GW), of which 23.86 percent or 3.68 GW was installed in the United States. Already a handful of countries have more than 15 percent of their electricity being generated from geothermal sources and they include; El Salvador, Kenya, the Philippines, Iceland, New Zealand and Costa Rica.

Being a renewable energy source, it is largely environment friendly, reliable and leaves little or no carbon footprint or noise pollution. But, asides its large upfront cost, another primary challenge with geothermal energy is that it runs the risk of triggering earthquakes. This is due to alterations in the Earth’s structure as a result of digging. However, since most geothermal plants are away from population centers (Location specific), the implications of these earthquakes are relatively minor. It is also difficult to sustain and in some situations geothermal energy sites are located further from the population, hence, requiring a vast network of distribution systems. This only adds up the overall cost of setting up a geothermal system.

Geothermal energy is largely untapped and if properly harnessed can go a very long way to helping reduce the number of homes yet to be connected to the grid while also take us a step closer to a cleaner safer environment.