The Swiss Energy Vault pilot project successfully tested the prototype of its so-called gravity power plant and received additional funding from Japan’s venture capital project SoftBank Vision Fund in the amount of USD 110 million to launch a demonstration industrial project in northern Italy.
The gravity power plant consists of a 150-160-meter tower, a pulley and crane system operated by a special computer program and a large number of concrete blocks of special form that accumulate energy and transfer it back to the grid using the laws of gravity. According to the company’s estimations, the efficiency of such a station can reach 90%, which combined with the simplicity, duration of storage and versatility of application can make it a new leader in the accumulation systems.
The modular units can go up and down at the same time, which enables the station to respond quickly to balancing needs. The station can increase power in 1 second from zero to 1.3 MWt, up to 4 MWt – in 2.9 seconds, and provide a linear work schedule or adjust it flexibly in milliseconds. Block moving devices (motors, cranes and pulleys) are standard equipment widely available on the market. The software is tailored to each station based on the base version developed by the company. The units have a unique manufacturing technology, developed jointly with the CEMEX Research & Development Center of Mexico, one of the world’s leading construction materials manufacturers, and can use industrial waste, assisting in the disposal of materials previously shipped to landfills.
In Italy, the company plans to build a demonstration project as a universal solution for the energy market, namely a 35 MWt gravity power plant that will be able to provide a flexible accumulation or output schedule, allowing to effectively ensure a continuous WPP / SES balancing for 8-10 hours. Such characteristics make it competitive with gas power plants, which are used as a first-line reserve for balancing the grid.
Several industrial projects in conjunction with solar generation are already planned for 2020. The financing received from the Japanese fund will also allow the company to refine the software and provide a feasibility study for the specific conditions of use of such technology in different climates.
The estimated cost of the project, in the range of USD 30-40 per 1 MWt per hour, can make the Energy Vault gravity power station an attractive element for SES / WPP projects by managing the amount of electricity that will be supplied to the grid. The combination of RES and such technology can significantly reduce the need for additional high maneuverability.