Electricity Storage, Heating and Cooling in One Device

Increase Profit

Amortized within 5 years* due to combined approach and energy costs reductions: Peak-shaving, increase of PV own consumption, optimized energy management & energy trading.

Reduce Emissions

Integrates renewable electricity (e.g. PV and wind) and replaces fossil fuels. Save yearly 94t CO2eq* by replacing e.g. a oil heating.

Become Green

Works with air and water only and is 100% recyclable. Save 81t CO2eq* by replacing the refrigerant of a heat pump and additionally avoid hazardous waste of a battery.

*Example calculation: 150kWel Green-Y device, peak-shaving in an office building

Do you want to save money and become green?

Get your Green-Y device with the following steps:

1. Consultancy by experts

2. Individual use case analysis

3. Free offer

Patented Compressed Air Technology

How Green-Y works: Compressing air creates heat and consumes electricity. Expanding air creates cold and generates electricity. These two main steps are performed separately in time. Therefore, Green-Y unifies the functionalities of a heat pump and a battery by storing electricity and generating heat and cold. The compressed air is stored in commercial pressure tanks which is a durable and inexpensive solution to store electricity.


Innovation: We essentially advanced the well-known compressed air energy storage technology by increasing the energy density by a factor of three and double the heat & cold extraction. This reduces the required storage volume by a factor of three and makes the decentralized application possible. Further, efficient heating and cooling is enabled directly in the building where the thermal energy is needed. The heat energy can be used to provide e.g. hot water for domestic use and room heating and the cold for e.g. cooling the building.

Technology Benefits


Working fluids: Water & air

100% recyclable


60% electrical efficiency

COP of 4


More than 20'000 cycles

Lifetime >50 years


Electricity storage far below 1 ct/kWhel