From pv USA magazine

The gravity energy storage tower developed by Energy Vault has reached commercialization, with the company signing an agreement with DG Fuels to provide 1.6 GWh of energy storage.

The tower will be charged with solar photovoltaic energy. Distributed storage will support the creation of renewable hydrogen, biogenic-based synthetic aviation fuel and diesel fuel.

The deal is expected to provide Energy Vault with $ 520 million in revenue across three projects. The first, a 500 MWh storage tower in Louisiana, is expected to start up in mid-2022. Other projects are planned in British Columbia and Ohio.

Energy Vault’s design includes a six-arm crane tower that lifts composite blocks using an electric motor (solar powered). The raised blocks are stacked, which creates potential energy. As the blocks are lowered, energy is collected and sent for use.

The tower is controlled by computer systems and machine vision software that orchestrate the charge and discharge cycles. A storage time range of two to 12 hours or more is achievable, the company said.

Energy Vault said the design of the tower is based on the physics of storing pumped hydroelectric energy. However, as a solid “moving mass”, composite blocks do not lose storage capacity over time. The company said the tower has 85% round-trip efficiency and a technical lifespan of over 35 years.

Composite blocks can be made inexpensively, the company said, using earth excavated from the construction site, wastes such as mine tailings and coal ash, and even fiberglass from wind turbines. downgraded.

DG Fuels will deploy the storage systems to power its process of converting carbon into fuel. The company said it was aiming for a 93% carbon efficiency rating for its aviation fuel. It will also use the energy from the tower to power the electrolysis of water for the production of hydrogen and oxygen.