Recent research led by Bin Liu from the School of Electrical and Information Engineering at Northeast Petroleum University in China has explored the thermal performance of Enhanced Geothermal Systems (EGS) using two different working fluids: water (H2O) and carbon dioxide (CO2). This study, published in the journal “Unconventional Resources,” addresses key challenges in geothermal energy production, particularly issues related to thermal storage life and energy consumption.
The research focuses on a specific area in the Gonghe Basin of Qinghai, where a three-dimensional model was developed to simulate the thermal-hydraulic-mechanical interactions within the geothermal reservoir. Using advanced COMSOL software, the team conducted numerical simulations to compare the heat production capabilities of H2O-EGS and CO2-EGS under various injection and extraction scenarios.
One of the significant findings of this study is that while H2O-EGS initially offers a higher heat extraction rate, CO2-EGS demonstrates a longer duration of stable heat production and a more energy-efficient process overall. Liu noted, “Although CO2-EGS has a lower heat extraction rate in the early stage of thermal recovery than H2O-EGS, it has a longer stable heat production time and a more energy-efficient heat production process.” This suggests that CO2 could be a more sustainable option for geothermal energy in the long run.
The implications of this research are substantial for the geothermal energy sector and related industries. As the world shifts toward cleaner energy sources, the ability to optimize geothermal systems using CO2 can lead to reduced operational costs and increased efficiency. This transition could attract investment from energy companies looking to enhance their portfolios with renewable energy options, particularly in regions with suitable geothermal resources.
Furthermore, the findings may open new avenues for carbon capture and storage initiatives, as utilizing CO2 in geothermal systems not only enhances energy production but also provides a method for sequestering carbon dioxide. The dual benefits of energy generation and environmental protection could make CO2-EGS an attractive solution for governments and corporations aiming to meet climate goals.
Overall, Bin Liu’s research highlights the potential of CO2 as a viable alternative to water in geothermal systems, presenting both economic and social advantages that could reshape the landscape of renewable energy production. As the industry continues to evolve, studies like this will be critical in guiding the development of more efficient and sustainable geothermal technologies.
