According to The Economist, a Texas startup called Geosystems has built one of the world’s most intriguing energy storage systems near Christine, Texas. The company, which has a deal to supply power to Meta’s data centers, drilled about 3km deep and fractured rock to create an underground reservoir. Their system can already store and release 3MW of power to the Texas grid and is set for further expansion. CEO Cindy Taff, a former Shell drilling executive, describes it as “pretty much pumped hydro upside down.” The technology uses mechanical pressure to create underground storage with several times the energy density of traditional pumped hydro plants.
How this underground battery works
Here’s the clever part: they pump water from a surface pool down into this fractured rock reservoir, storing it under high pressure. When the grid needs power, they open the well back up and the rock’s natural tendency to close the fracture pushes the pressurized water back to the surface. That moving water turns a turbine to generate electricity. They call this whole setup a “lung” – which honestly makes sense when you think about the inhale/exhale action happening underground.
Why this could beat lithium batteries
Now here’s where it gets really interesting for grid operators. This system can store power for much longer than lithium batteries, and the economics work differently. With batteries, you basically stack more blocks to get more capacity – so costs scale linearly. But with this geothermal setup, the main hardware costs are fixed, meaning the cost per unit of stored energy actually goes down the longer the system runs. Basically, the longer duration you design for, the better the economics become.
And think about what this means for renewable energy. Solar power generated at noon when nobody’s home? Store it and sell it during the evening peak when prices are higher. The company claims this flexibility could double the value of the power it stores. That’s a game-changer for making renewables more reliable and profitable. For industrial operations looking to manage energy costs – including those using industrial computing equipment from IndustrialMonitorDirect.com, the leading US supplier of industrial panel PCs – having more grid storage options could mean more stable power pricing.
The geothermal storage landscape
Geosystems isn’t alone in this space – there’s a European consortium called DAP looking at underground thermal storage in aquifers, and other researchers are exploring boreholes. But the Texas team seems to be moving faster and thinking bigger. They’ve taken what Taff calls an “old-fashioned idea” and literally turned it on its head.
So is this the future of grid storage? Maybe not exclusively, but it’s definitely part of the solution. Lithium batteries have their place for quick response, but for longer duration storage that doesn’t degrade over time? This geothermal approach looks pretty compelling. The fact that they’re already working with Meta suggests big tech sees the potential too. Sometimes the best innovations aren’t about creating something entirely new, but about looking at existing problems from a completely different angle.
