After explaining geothermal energy, which is one of the clean energy sources, we will explain the new generation geothermal energy, which theoretically opens the door to our endless energy source.
The only real problem the world is facing is global warming. Due to carbon emissions, deforestation and so on, the earth is warming by 1.5 degrees Celsius every year. It is stated that if measures are not taken, this degree will rise to 2 degrees Celsius in fifteen or twenty years, and then to 2.5 and 3 degrees Celsius.
Another degree Celsius of warming on our planet means the extinction of many species, the shrinking of the remaining habitats, and people having to live in worse conditions. It is estimated that a warming of 3 – 4 degrees Celsius will turn the world into a difficult place to live, even for us.
For this reason, global organizations are calling on the world to urgently gather for the solution of this crisis. In 2015, 191 countries party to the Paris Climate Agreement agreed to keep warming below at least 2 degrees Celsius. The world needs to reduce its carbon emissions to zero as soon as possible and stop global warming.
One of the main ways to do this is to get rid of fossil fuels. However, it is not that easy. It is necessary to completely change the engineering perspective that has been going on since the industrial revolution and to find new unconsidered solutions. New technologies for clean energy are not immediately accepted because they are expensive, and more investment is needed to make them cheaper.
When it becomes difficult for private enterprises to meet their profitability targets, governments need to invest in clean energy sources with funds. Monopolies enriched with fossil fuels need to invest the money they earn in this field into clean energy, which is the future of the world.
That’s what they do.
This article is about the future of clean energy. On the combination of an energy form that has not been talked about much before in the field of clean energy with a revolutionary technology.
What we are talking about is not solar or wind energy. What we will talk about is a renewable energy source that has been used for 200 years. New generation Geothermal.
Geothermal Energy is Preparing For a Big Explosion
A few next-generation startups may have found a scalable and easy way to provide 100% clean energy to everyone on the planet. Geothermal energy, which has been used in private areas until today, may soon appear as a new and general energy type for the whole world.
In order to better understand the revolutionary idea that geothermal energy meets, we need to talk a little about geothermal energy first.
What is Geothermal Energy?
Magma, the core of the earth, has a temperature at least as high as the surface of the sun. We encounter a temperature ranging from 6 thousand degrees Celsius to 10 thousand degrees Celsius, 4 thousand kilometers under the ground on which we step.
The energy here is so great that even taking advantage of it for a moment can meet the energy needs of all humanity twice. There are studies showing that only one thousandth of the world’s heat core will be enough to meet the energy needed by humanity for 2 million years. Considering that the core of the earth will remain hot as long as the earth exists, it is possible to say that we have an energy source that will last until the end of the earth, that is, a theoretically infinite energy source.
There are a few engineering challenges that need to be overcome just to harness this energy, and they mature over time and are overcome one by one.
In some parts of the world, we see that some of this heat can be transported to or near the earth’s surface thanks to the permeable layers. Even when we are only a few kilometers down from the earth’s crust, we can encounter enough heat to provide energy.
Until now, we have been using geothermal energy only in regions with these special permeable layers. In other words, it was used either in areas where there was a fault rupture or in areas where the water gushing out to the earth (geysers) was dense, as it could not withstand the pressure it was exposed to with the heat coming from under it.
Let’s go even older. Even primitive peoples used this energy for bathing. However, it started to be used in the 1860s to produce heat and electrical energy as we know it today. Since the 1960s, commercial initiatives have emerged to convert heat into electricity and they continue to exist today.
There are four basic methods to obtain energy from underground heat.
Four Basic Geothermal Energy Facilities
1) Traditional Geothermal Energy Facilities
These are located close to areas of volcanism or fault ruptures and are generally used for heating purposes. There are hot springs around. They work with the geothermal energy that comes to the surface spontaneously and are common. However, unless very specific areas are discovered – which is a difficult and expensive process to explore – they are not an efficient option for generating electricity, as high temperatures are required to generate electricity.
They generally have a temperature between 24 degrees and 370 degrees. For more warmth, it is necessary to go underground. When it goes underground, the liquid taken from these places is cooled and pumped back to the place where it is taken through an injection box to maintain the pressure.
Most facilities operating today are like this. To obtain energy, special locations have to be found. Therefore, traditional geothermal power plants are a difficult and expensive solution depending on geography. However, it is still used where it is profitable.
In 2019, the electricity capacity produced from geothermal energy has reached 15.4 GW worldwide.
2) Advanced Geothermal Energy Facilities
As explained above, traditional geothermal energy could be used in geographically limited areas. However, the situation is different in advanced geothermal power plants. For the establishment of these facilities, engineers go underground and create their own geothermal energy resources.
For this, they inject water into a large underground rock and increase the temperature and pressure of the water in this rock with the temperature underground, allowing it to rise to the surface. After obtaining electricity and heat energy from this hot water, they inject it into the rock again. However, although this method removes the geographical limitation, it is not yet scalable and as the source gets deeper, accessing and drilling the rock becomes a challenging task.
Despite everything, funding support was provided by the US government during the Obama era in the 2010s for these energy facilities, which could theoretically be installed anywhere in the world.
It is estimated that a temperature of at least 150 degrees Celsius is reached when descending to an average depth of 6 kilometers, and only the geothermal energy sources in the USA have an electrical capacity of 5 GW. If you try to use these facilities only for heating, it is predicted that 15 million terawatts of energy can be provided, and that residential and commercial spaces in the USA can be heated for 8500 years.
3) Super Rock Geothermal Energy Facilities
When you dig deeper and find larger rocks and warmer ground, the rewards are greater despite the tough engineering challenges. Here we are talking about a water temperature exceeding 373 degrees Celsius and a pressure of 220 bar. Water exposed to this pressure and temperature transitions into a form called supercritical. This situation changes the chemistry of the water and can cause it to behave outside of its usual behavior. To date, there are only a few concrete examples where water has passed into the supercritical stage. Chemists are working on it.
The key advantage of super rock geothermal plants is that they are twice as efficient as advanced geothermal power plants in converting high heat into energy. Below you can see the costs per Mw of energy types produced.
Here’s what has been experienced so far: The higher the depth and temperature you reach, the more yield you get.
4) Advanced Technology Geothermal Facilites
Here, the revolutionary technology that is the subject of our article, will be in these facilities, dear reader. I say in these facilities because it has not yet been fully implemented in a concrete way, except for the trial projects that a few small initiatives have set up with government support to try out.
The basic principle on which the method is based is as follows: You send the water you take from nature down with your special drilling system that can go down 20 kilometers below the ground. Since the water that literally boils like crazy there, cannot withstand the pressure brought by the boiling and water is pumped from above, it starts to rise from the other side by itself, and at the end of the adventure, this water is sent down again after heat and electrical energy is produced. This cycle can last until the magma cools, that is, theoretically, indefinitely for us.
No liquid is taken from nature or given to it. A closed loop is established. This cycle has zero carbon emissions. As powerful as fossil fuels. It does not take up as much space as solar power plants. It is not dependent on natural conditions like wind energy. It does not interfere with the balance of nature. It can even be said that with increasing humidity, the plant increases the forests around it and supports wildlife.
Below you can see the promotional video of an startup called Quiase, which is trying to implement this idea.
In fact, this technology has been around for decades, but with the huge companies from fossil fuels investing in this field, it has only been in the trial phase.
Of course, there are unbelievably big engineering problems in front of this business. Drilling 20 kilometers underground is very, very difficult. In some areas it is almost impossible to do with today’s technology.
It remains unclear how alloys or elements that can withstand water, temperature and pressure in the supercritical phase, whose behavior cannot be fully predicted 20 kilometers underground, will be processed and how long they will be able to function undamaged.
Problems and Uncertainties
First of all, it should be noted: It has been discussed for a long time whether the seismic activity of geothermal energy initiatives, and as a result, the movement of faults will cause an earthquake. This is very feared, but the data show us that the probability is higher in the extraction of the fossil fuels oil and natural gas. However, the terms of the specifications for the opening of geothermal plants are more difficult than those of fossil fuels. This is a good thing. If we are going to produce clean energy, we need to do it in the cleanest and safest way.
Second, alloys or elements based on high temperature and pressure need to be processed or strengthened. I don’t know which element or alloy to use for this. For example, the melting temperature of iron is 1540 degrees Celsius, but how much pressure can it withstand? Platinum melts at 1768 degrees. Tungsten, on the other hand, withstands 3422 degrees Celsius and is relatively inexpensive, but what will tungsten do when it sees that much pressure? It is unclear how water that has reached the supercritical stage will behave with tungsten.
Third, even if these methods are found, drilling to go down to a depth of 20 kilometers will be a very costly drilling. As the rock type gets harder and the depth increases, there must be a drilling process in which brand new methods are discovered where diamond bits are not enough.
However, it is possible to see that humanity has overcome these problems theoretically and can make them perfect in practice with a little research.
Can we think that the energy crisis and the injustices and wars caused by this crisis will come to an end when this is done? Or that people can escape from poverty and bad conditions?
We do not know if other sociological processes will be involved, but we want to continue to produce content related to these developments so that we can look at the future of the world with some hope.
Let me also point out that I made great use of a summary translation from a work published in Vox to compose the article.