Using air and water to create a clean and efficient energy storage system

There is no doubt that renewable energies are the future. However, there is still a lack of cost-effective, sustainable electricity storage systems to make energy available around the clock.

Green-Y, a Swiss start-up founded in 2020, has developed a compressed air power storage unit that can heat and cool, combining the functions of a battery and a heat pump in a single device. Unlike batteries, the system does not rely on rare raw materials that are often harmful to the climate.

The Solar Impulse Foundation has awarded the Solar Impulse Efficient Solution Label to the young Bern-based company for its eco-innovative solution. The product's high potential is also backed up by a research study conducted by Global Market Insights, which claims that the market for energy storage systems will cross a valuation of USD 3.5 billion by 2032.

In a residential building, the Green-Y system stores the electricity from solar panels and provides heat for hot water and heating as well as cold for cooling. Thus, solar electricity is used efficiently, self-consumption increases and energy costs decrease. The principle behind it is based on a compressed air storage system. The compression of air allows electricity to be stored and generates heat at the same time. When electricity is generated, the filled compressed air tanks are relieved, creating cold. The combination of the electricity and heat sectors solves the problem of energy storage in an intelligent and sustainable way. For users, the company promises substantial savings in energy costs, which should mean that expenditure is recouped within five years.

The recently constructed Switzerland Innovation Park in Biel/Bienne was the first building to integrate Green-Y's compressed air storage technology in 2021. Boosting solar energy self-consumption and delivering renewable heat and cold has helped to increase the sustainability and profitability of the building.