Geothermal Energy Production: Not the Most Sustainable Option

I learned a lot about geothermal energy production through my mini-term to New Zealand. There, geothermal energy is ideal because of New Zealand’s geographic location, which is located near where two tectonic plates meet. Geothermal energy production works via using the heat and thus energy from inside the Earth to make power. This works by pumping geothermal fluid out of the ground, converting the heat into steam, and having this steam go through turbines and turn the turbines so create energy. This is done on a large scale in New Zealand to create electricity, but there is also smaller-scale geothermal energy that people can use to heat their homes. The New Zealand geothermal practices are so successful due to the location near tectonic plates that have heat closer to the Earth’s surface, which means that other locations are much less ideal for geothermal energy production and make this practice less efficient. Geothermal energy production can be quite problematic due to the geothermal fluid itself–prior to the late 1990s, geothermal fluid was dumped into rivers after the fluid was used to create steam. This ended up polluting a lot of rivers and raising the river temperature as well as allowing for harmful, poisonous bacteria and algae to grow in rivers, killing off the wildlife. The Resource Management Act has thus put restrictions on how geothermal fluid is dealt with after the energy production process. Fluid is now pumped back into the ground after the fluid is used, to attempt to recycle the geothermal fluid. This is still quite problematic because the fluid can build up in certain locations and erupt out of the ground. Another problem that occurs is the shifting levels of the ground. When the geothermal fluid is placed back in the ground, this can also contaminate the ground water and thus our crops, since the crops are now interacting with harmful, toxic materials. Pumping the fluid back into the ground can get quite expensive, and the cleanup of the rivers in New Zealand that have been previously destroyed by this practice is extremely expensive. This is definitely not a widely commercialized practice, and I really don’t think it should be (alternatives such as solar and wind power are much better for the environment with fewer negative drawbacks). In terms of long-term sustainability, I don’t see this practice being incredibly sustainable due to the negative environmental drawbacks. However, the fluid can keep being re-used, which is a slight positive when compared to things such as coal burning or fossil fuel usage.