Energy Vault is the first off the blocks and funded via a SPAC lto build gravity blocks with heavy blocks. These heavy blocks weigh 30 tonnes. Blocks can be recycled. Local waste mining materials are locally sourced. Gravity and kenetic energy provides the underlying technology. The physics is similar in concept to pumped hydro but has lower capital cost and more operational automation.
Energy Vault completed the mechanical construction of the first of its kind, grid-scale unit located in Switzerland (Ticino). This commercial-scale system is a 1:4 scale pilot system . Validation of building with all core technology elements occurred in 2018. The project connects to the Swiss national utility grid and is undergoing testing and software commissioning.
Warning: Much hype. (See AFR) The potential for Energy Vault’s gravity-based, building block storage technology has attracted some of the world’s biggest participants in the decarbonisation journey – Saudi Aramco, BHP and now Korea Zinc. The Swiss company says they have a potential of $US32 billion ($44.6 billion) of projects using the technology. Deployment may take five-10 years.
Gravity Batteries in Large Sites
Interesting Engineering reports in April 2023 that Energy Vault is now completing two such units, which are situated near Shanghai in China and Texas in the United States.
- Energy Vault batteries are proprietary and made from ultra-low-cost materials such as cement/polymer-based composites.
- These materials include soil, mine tailings, coal ash, incinerated city waste, and other remediation materials.
- The density of the materials is up to 2 times greater than water.
- The project is with China Tianying, a waste management and recycling company, and is designed to have an energy storage capacity of 100 MWh.
The gravity battery pilot for Texas is for energy firm Enel with a 460-foot-tall structure. The total capacity of the project will stand at 36MWh.
|Company||Stage||Web Site, more information|
|Energy Vault||First Commercial, building first 100MWh plant||Energy Vault|
|Gravitricity||Pilot. Crowd funding During 2021 successfully constructed, commissioned, and operated a 250kW, grid-connected demonstration project using a 15 metre high rig at the Port of Leith, Edinburgh.|
The demonstrator uses two 25-tonnes weights suspended by steel cables.
Scoping out disused mines that have deep shafts
|Gravity Power||Gravity Power is just a small step away from pumped hydro. They dig a deep shaft, using standard technology from the mining industry, then build a piston of reinforced rock in the shaft. They add water and cap it, creating a closed loop system, with no additional water required. It uses renewable energy to pump water under a heavy piston and lift it. When power is needed, the piston weight is released, forcing the water through a hydroelectric generator.|
Watch their video here. https://www.gravitypower.net/
|New Energy Let’s Go||They use hydraulic lifting of a large rock mass. Using electrical pumps, as already used today in pumped storage power plants, water is pumped beneath a movable rock piston, thereby lifting the rock mass. During times of insufficient generation of renewable power, the water which is under high pressure from the rock mass, is routed to a turbine, as in conventional hydroelectric plants, and generates electricity using a generator.|
The company is looking for a buy – the inventor Heindl Energy GmbH ran out of money.
Cost of Gravity Batteries
Gravimetric did a report in 2019 that showed construction, running costs, and maintenance were :
- Gravity storage = for 25-year project, estimated = $171 MWh
- Lifetime cost for lithium-ion batteries = $367
- Flow batteries = $274 MWh (for more on flow batteries, click here)