Wind energy produces electricity by harnessing the power of the wind. When there is wind. As with other renewable energies, such as solar energy, the availability of wind energy is not continuous and its production is difficult to anticipate because it depends on the vagaries of the weather or the day-night cycle.
The obvious solution is to store the electricity produced by wind turbines in batteries when there is excess production and then use that electricity when electricity demand increases or when there is no wind. However, the cost of batteries is a major obstacle, and relatively modest battery installations, even domestic ones, currently have a high economic cost.
More common is to use electric pumps powered by wind or solar energy to pump water in a dam or reservoir located at high altitude. In this way, when electricity is needed, it can be produced by letting the water fall through a hydraulic turbine that converts it into electrical energy, as happens in a hydroelectric power station.
Electricity produced "by gravity
The proposal for Energy Vault is based on the same principle of converting kinetic energy, movement, into electricity. So using a series of cranes and concrete blocks, it takes advantage of moments of high wind or solar electricity production to lift up to 5,000 concrete blocks. Later (hours, days or even months later), when the demand for electricity increases or when there is no wind or sun, the same concrete blocks are lowered using gravity.
And when the concrete blocks are allowed to "fall" under the force of gravity, they move alternators as they descend, which, in a similar way to hydraulic turbines, produce clean electricity.
