The Utilization of Underground Water has the Potential to Become a Significant Renewable Energy Source

A recent study published in the journal Applied Energy has found that Aquifer Thermal Energy Storage (ATES) has the potential to reduce natural gas and electricity consumption in the heating and cooling sector of the United States by up to 40%. The study also highlighted that ATES has the ability to prevent blackouts caused by high power demand during extreme weather events.

“We need storage to absorb the fluctuating energy from solar and wind, and most people are interested in batteries and other kinds of electrical storage. But we were wondering whether there’s any opportunity to use geothermal energy storage because heating and cooling is such a predominant part of the energy demand for buildings,” said study first author A.T.D Perera. “We found that, with ATES, a huge amount of energy can be stored, and it can be stored for a long period of time.”

ATES functions by extracting water from pre-existing underground reservoirs and heating it on the surface during summers using environmental heat or surplus solar energy. It can also be heated using wind energy throughout the year. The water is subsequently returned to the underground reservoir for use in warming buildings during winter or cooling them during hot summer months.

The Earth acts as a good insulator, allowing the water to maintain its temperature even after months of storage. “It’s a way of storing energy as temperature underground,” said Peter Nico, the individual who leads the Resilient Energy, Water and Infrastructure Domain and holds the position of deputy director at Berkeley Lab’s Energy Geosciences Division.

Although ATES systems are not extensively utilized in the United States, they have gained global recognition, particularly in the Netherlands. One key advantage of these systems is that they acquire cost-free thermal energy from variations in temperature throughout the year, which can be reinforced by electrically generated heating and cooling.

The researchers created a scenario to determine the potential benefits of utilizing ATES, which involved a computational model of a neighborhood in Chicago made up of 58 two-story, single-family buildings. This was done to analyze the practicality and durability of the ATES system in the face of changing climate conditions.

The team conducted a test on the efficiency of ATES by analyzing future climate projections to determine the proportion of the neighborhood’s total energy budget that is being consumed by heating and cooling requirements, and how these requirements could evolve in the future. They developed a microgrid simulation for the neighborhood that integrated renewable energy technologies and ATES to assess its effectiveness. According to the findings, the utilization of ATES in the power network could result in a decline of up to 40 percent in the usage of fossil fuels.

Although ATES is more expensive than current energy storage technologies by 15 to 20 percent, the experts are optimistic that its efficiency would compensate for the higher costs after a few years of development. “But, on the other hand, energy storage technologies are having sharp cost reductions, and after just a few years of developing ATES, we could easily break even. That’s why it’s quite important that we start to invest in this research and start building real-world prototype systems,” said study co-author Professor Rizwan-uddin Perera.

ATES offers several benefits compared to above-ground water or ice storage systems. It requires less space and is highly efficient, making it suitable for large-scale heating or cooling in a community.

ATES has an additional advantage in that it can enhance its efficiency with the worsening weather conditions due to climate change. Although the extreme hot summers and severe winters anticipated by the top climate models will have numerous negative consequences, they could also amplify the quantity of cost-free thermal energy that ATES can accumulate.

Leave a Comment