Cemex R&D subsidiary sees the ups and downs of energy storage

Crane-suspended concrete segments, patterned like an enormous stave silo, power a commercial scale-ready system announced last month at Energy Storage North America in Pasadena, Calif. The technology is based on what Swiss developer Energy Vault describes as “the principles that underpin traditional gravity-based pumped hydro plants. The new technology combines conventional physics fundamentals of potential and kinetic energy with a proprietary, cloud-based software platform.”



Energy Vault’s method of storing and discharging energy is based on hydropower fundamentals, but replaces water with 35-ton segments cast from concrete bearing a variety of virgin or recycled materials, depending on country and market. The firm illustrates the 35-MWh storage system fully charged to fully discharged, proving the energy embodied in the transfer of thousands of tons of concrete.

The software operates a newly developed, fully automated six-arm crane and orchestrates positioning of the concrete segments that provide the basis for efficient electricity storage and discharge at wind farms. The use of low cost and environmentally-friendly concrete materials enables the system to achieve low cost per kilowatt-hour and high round trip efficiency while delivering a 30-40 year life without any degradation in storage capacity. Energy Vault figures that a properly configured system will be capable of reaching 100 percent of target power levels in 2.9 seconds.

Energy Vault unveiled plans for a charter crane and segment installation in India next year, plus initial agreements with customers on multiple continents. A new technology and commercial partnership with a Swiss subsidiary of Mexico-based Cemex S.A.B. de C.V. will focus on optimization of various concrete based materials conducive to system deployments at wind energy operations the world over.

“Energy Vault’s team has developed a disruptive platform, and we are enthusiastic to work with [them] to deploy an environmentally efficient and cost-effective energy storage solution that is highly viable,” says Cemex Global R&D and IP Head Dr. David Zampini. “We share a common commitment to enable a future where resources are used responsibly, which is paramount to Cemex’s strategy for sustainable development.”

“Innovation in energy storage represents the largest and most near term opportunity to accelerate renewable deployments and bring us closer to replacing fossil fuels as the primary source to meet the world’s continual growth in energy demand,” notes Bill Gross, Energy Vault co-founder and founder of the technology incubator, Idealab, from which the crane/concrete segment storage concept emerged.

“The world needs rapidly scalable and sustainable energy storage solutions to meet one of the most urgent challenges—the need to decarbonize our energy generation—and we’re thrilled to launch Energy Vault’s unique technology to help solve this problem,” adds Energy Vault CEO and co-founder Robert Piconi. “In addition to the vital environmental benefits it provides, the system’s radical reduction in $kWh and overall levelized cost of storage enables our customers to provide dispatchable and baseload power cheaper than fossil fuels for the very first time. We’re also excited to begin our important collaboration with Cemex whose innovation in material composite technologies and global footprint will help accelerate achieving our collective sustainability goals.”