Can Geothermal Energy Solve Climate Change ?

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Yellowstone National Park, Wyoming. Photo credit: Jim Stimac

Climate change has had an enormous impact on our planet and is continuing to affect our earth daily. While climate science is fairly complicated; the majority of the world’s climate scientists are in agreement that carbon emissions are changing the climate in ways that are changing global temperatures. In 2019 alone, the world has released around 37 billion tons more. That’s 50% more than the world emissions in the year 2000 and almost three times emissions as much as 50 years ago. As we look into the future, the world’s population, according to the World Bank, will reach 10 billion by 2050. These projections mean that the world’s energy consumption is only going to be higher and consequently carbon emissions will keep rising despite the need to be reduced to zero. One promising solution that can help meet the world’s growing energy needs while having low emissions is Geothermal Energy.

Geothermal energy is thermal energy that is stored in the deep layers of the earth. The earth’s core is believed to be made of molten iron, and the heat from this molten core dissipates towards the outer solid crust. This heat can then be extracted from deep earth and be used to heat water to produce steam that spins a turbine to produce renewable low carbon electricity. One advantage to geothermal is that it is capable of producing reliable and secure renewable electricity that contributes to energy resiliency.

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Geothermal Electricity Production — Image by DOE

The good news is that Geothermal energy emits a minimal amount of carbon and carbon equivalent emissions (mainly sulphur dioxide and hydrogen sulphide) due to the nature of the geothermal basins where some of the gasses present in the basins of the geothermal wells vent to the atmosphere.

The catch with geothermal energy is that while earth’s this energy is abundant, geothermal energy, similar to hydro power, has geographical limitations where energy projects would be feasible. Specifically, locations where higher tectonic plate activity is present, for example see below where western US has more abundant (red) thermal energy per square meter compared to the east (blue).

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Geothermal Heat flow map of the continental U.S in 2011 by SMU Geothermal Laboratory and Dr. Blackwell, Temperature at 7 km Depth

The catch with geothermal energy is that while earth’s Geothermal energy is abundant, it has geographical limitations.

The State of Geothermal

In 2019, the world added almost 0.8 GW of geothermal power. This is the highest level ever recorded. Thanks to Turkey, Indonesia, and Kenya, who were by far the largest contributors to this increase, together accounting for three-quarters of the global increase. These three countries are also expected to continue leading geothermal power growth until 2021. Overall, the outlook for global additions of geothermal power is promising but nowhere near where it needs to be.

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Indonesian Geothermal Plant — KS Orka Renewables

Low carbon energy transition and the future of geothermal energy

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Electricity Generation Plant by footprint comparison

There is tremendous opportunity for the fossil fuel industry to provide technology and expertise that make geothermal energy economically attractive for all energy users around the globe.

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Renewable power produced for same capacity for various sources

The costs of a geothermal energy system depend on the system size, and how long it will last. The larger the system, the larger the investment required, and the lower the electricity prices. Despite the reliability, availability, and lower footprint requirements, Geothermal energy is poised to have strong competition with Solar PV and Wind in terms of cost of electricity production in the next 30 years. Unless Geothermal technology has multiple breakthroughs (which is not uncommon), solar and PV may have better running cost of electricity compared to geothermal energy. Nevertheless, the cost premium to using geothermal energy will materialize for applications where high reliability, availability, and high temperatures are required. As well as other economic considerations such as the cost of adding energy storage to solar and wind project to match the equivalent of geothermal project.

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Projected cost of electricity from Different Sources over the next 30 years, DOE Estimates

An exciting opportunity for geothermal energy is utilizing energy that has relatively lower temperatures. One can use this energy to build thermal loops (open or closed) that provide thermal energy for distributed energy, district energy and for medium scale commercial and residential applications. Such advanced geothermal systems present a striking opportunity for consumers to tap into reliable continuous renewable power.

Perhaps the most exciting opportunity for geothermal energy is that it can help solve a global problem while we aim for low carbon energy systems by 2050. This is integrating the fossil fuel (oil and gas) industry into a low carbon future. The geothermal industry and the oil and gas industry use similar steps and technologies to locate and drill resources that are then used to produce energy. Geothermal projects require technology that facilitates drilling and maintaining geothermal basins for every project. Numerous advancements in geothermal technologies have been supported by adapting oil and gas technologies to requirements beyond traditional limits. There is tremendous opportunity for the fossil fuel industry to provide technology and expertise that make geothermal energy economically attractive for all energy users around the globe. Geothermal projects proved to create multiple times more long-term jobs compared to wind and solar. If players in this industry are able to achieve this, they will become an essential part of the transition without being left out.

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Long-term jobs Created per 1000 Homes powered, California Based, DOE