The future of our planet depends on how much renewable energy we can generate. Everything that humans do requires some form of energy. Many years ago that energy only came in the form of work done by the people themselves and when they got creative they started using horses. Throughout the ages certain geniuses have figured out new ways to harness ever larger quantities of energy. All of this energy has been generated from multiple energy sources. Of course us mere humans can’t create energy, we can only change its form into something useful.
I’ve been working for a large geothermal company for the last eight years as a mechanical engineer. This experience has taught me the ins and outs of the energy world. I have seen projections of how our energy demand is going to keep increasing into the foreseeable future. There is no one solution to our energy future. It is going to take a combination of energy sources including several existing technologies as well as some new technologies which have not been developed yet. In this blog I will discuss the current state of renewable energy technology, track where these technologies are trending, and explore some cutting edge technologies which are still in their infancy.
To start you all off, I will discuss a form of renewable energy that is near and dear to my heart. GEOTHERMAL. It always shocks me how little if anything at all people actually know about geothermal power. The basics are geo = earth and thermal = heat so geothermal power is literally taking heat out of the center of the earth. That heat is transported out of the earth by means of either water of steam. Geothermal power plants require two key ingredients. 1. A geological structure which has a lot of water underground, and 2. An area where high temperatures can be found near the surface of the earth. You can often tell there is a geothermal resource in the area where there are naturally occurring hot springs.
There are two categories of geothermal power plants. First, there are the old school plants that take steam straight out of the ground and send that steam directly through a steam turbine to spin a generator and create electricity. Second, there are some plants that pull hot water out of the ground and through a series of heat exchangers and a process called the Rankine Cycle, the heat is extracted from the earth, and used to boil a secondary fluid which spins a turbine/ generator and creates electricity.
The future of the geothermal industry which will make it much more accessible around the globe is called enhanced geothermal systems (EGS) a.k.a hot dry rock. In these systems, people will create their own cracks underground, and pump water into the ground which was previously dry. This will create a geothermal system that can be used to generate electricity. It is basically a human made geothermal system and the advantage is that it can be done in significantly more locations than geothermal systems naturally occur.