Quidnet Energy recently secured a $10-million equity investment from Hunt Energy Network (HEN) to scale up its geopressured energy storage concept and create 300 MW of geomechanical energy storage projects across Texas.
Founded in 2013, Houston-based Quidnet has developed a method that relies on existing oil and gas drilling technologies alongside hydropower equipment to store excess energy from power plants or renewable systems. This stored energy can be returned to the grid during periods of peak demand.
The process involves drilling into a target reservoir, such as shallow, thermally immature shale formations, and hydraulically fracturing it to create a storage space. Water is injected into the open fracture network and pressurized by rock deformation and overburden stresses. When the pressurized water is flowed back to the surface, it is run through a turbine to generate power.
Over the past several years, Quidnet has tested its technology in various locations in the US and Canada. Based on this prior work, some details of which were shared in a 2023 conference paper (SPE 212347), the company believes it can achieve power outputs of 1 to 10 MW for 10 hours or longer from a single storage well.
Quidnet’s push to commercialize comes amid a battery boom in places like Texas, which went from virtually no battery storage in 2020 to more than 4,000 MW of capacity at the start of the year. That figure is expected to rise to more than 10,000 MW, or over 10 GW, by the end of the year, making Texas the US leader in installed battery capacity over California.
Joe Zhou, CEO of Quidnet, remains undaunted by such projections, noting that most grid-scale batteries have durations of about an hour. He said this highlights a significant opportunity for long-duration storage systems.
“Despite the decades and half a trillion dollars that’s gone into it, lithium ion is just not going to get us there in terms of the extensive storage needs that we have,” Zhou, who previously worked in the industrial battery sector, told JPT. “We need something radically different from a cost and scale perspective and that’s ultimately the role that we’re going to fill here.”
Zhou shared that the newly announced 300 MW target may result in up to 100 storage wells drilled in Texas where officials are seeking solutions to alleviate the strain on the state’s electric grid.
Quidnet is pursuing a similar path as Sage Geosystems, another Houston-based firm. In February, Sage Geosystems secured $17 million in equity funding to build a 3-MW geomechanical energy storage system in Texas and is also conducting a separate feasibility study for the US Department of Defense.
One of the biggest challenges Quidnet faces in reaching such numbers involves its ability to maintain an adequate storage volume and pressure within a given geologic formation.
The concern is not so much about fluids leaking off into the matrix but at the fracture tips, which Zhou described as the critical “weak point” within the reservoir. “What we've been spending a lot of time on is to control for that because, at least from what we see in the field, the [fracture] tips themselves are not going to hold back the pressure,” he added.
The company’s mitigation efforts are shared in its recent SPE paper which speaks to the testing of a viscous sealing slurry made from a mixture of bentonite and friction reducer. In one case, the slurry reduced leakoff rates by 80%, while more than 85% of the initial post-injection pressure was retained for a 24-hour period, compared to less than 30% in untreated rock.
The deal between Quidnet and HEN is what’s known as a build-and-transfer partnership. Quidnet will design the projects and then hand them off to HEN, which will provide the capital to build and own the storage sites.
Among the projects they will collaborate on is an agreement with utility CPS Energy which selected Quidnet in 2022 to provide up to 15 MW of storage capacity around San Antonio, Texas.
Launched in 2018, Dallas-based HEN is part of Hunt Consolidated, the parent company of industry stalwart Hunt Energy, and brings experience in developing energy storage projects. Zhou said this background will be crucial for Quidnet’s commercialization efforts in the power sector, which is defined by nuances and permitting processes that can take years to navigate, even for the most-seasoned firms.
“It’s one thing to get the wells to work but it’s actually another business and another set of competencies entirely to bring those wells online and tie them into the grid,” he said, adding that HEN holds “a lot of latent knowledge that they can teach us.”
As part of the agreement, Todd Benson, chief innovation officer of Hunt Energy, has joined Quidnet's board of directors. Benson previously held an executive role at the drilling contractor Helmerich & Payne following its acquisition of Motive Drilling Technologies in 2017, a software firm he founded and led as CEO.
The new funding from HEN brings Quidnet’s total to $45 million in private capital raised along with $20 million in government contracts.
For Further Reading
SPE 212347 Geomechanical Pumped Storage in Hydraulic Fractures by H. Schmidt, S. Wright, C. Mauroner, H. Lau, B. Hill, and J. Zhou, Quidnet Energy; and A. Bunger, University of Pittsburgh.
