EarthBridge Energy has acquired acreage in West Texas for an energy storage project the Houston-based company plans to develop.
The company plans to deploy its GeoBattery energy storage technology as part of a hybrid energy development that would include onsite renewable resources.
The technology uses excess electricity from wind and solar farms to pump water into and out of underground reservoirs as a means of storing energy. The process can store energy for between 10 and 1,000 hours and has the potential to bring the installed cost of long duration energy storage to below $10 per kilowatt hour, enabling the deployment of 100 percent carbon oxide free energy at scale, the company said.
To charge, the system draws water from an underground reservoir via a well. At the surface, some of the water is heated and some is chilled by an electrical heat pump. The heated and chilled water are then stored in different zones of an underground reservoir or in different reservoirs.
To discharge, the system brings the heated and chilled water back to the surface where the heat pump system is reversed and used to drive a turbine that converts the thermal energy back to electricity. The outflow water is directed back to the source well.
“Because no geothermal resource is needed, the GeoBattery is highly scalable with global applicability,” the company said via email, adding that because it does not require hot geothermal sources, it can be deployed anywhere a well can be drilled for water. Major sedimentary basins are a sweet spot, EarthBridge said.
EarthBridge said it intends to mainly monetize its technology using price arbitrage in the wholesale energy market, adding that the technology can be deployed in front of the meter, like any generating facility, or behind-the-meter through a power purchase agreement with a wind or solar farm or as an asset sale with a development fee.
There has been growing interest in using the resources and expertise of Texas’ oil and gas industry to aid the transition to a less carbon dioxide intensive energy economy.
A recent study by the University Lands Office, the International Energy Agency and researchers at Texas universities found that almost 80 percent of oil and gas entities interviewed said they already have a geothermal strategy in place or in development.
And although Texas’ subsurface geothermal energy is not as robust as resources in regions with latent volcanic activity, such as California and Nevada where geothermal energy has been used for decades to power turbines, the report noted that Texas’ oil and gas industry is well equipped to drill to tap subsurface geothermal heat that could be used in a variety of novel technologies.
The report noted that Texas has several distinct zones with varying degrees of potential heat energy. Overall, the report found that the geothermal heat beneath the surface of Texas is approximately equal to 163,000 billion barrels of oil equivalent, or roughly half a million times its annual electricity generation of 500 million megawatt hours in geothermal energy potential, though the authors cautioned the estimates are of energy content, not extractable energy.
