Newly developed and patent-pending air-cycle 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. Our unique technology yields a game changing high energy density which makes a decentralized application possible. As a result, Green-Y can be installed locally where electricity, heat and cold are needed. Transportation losses and the need of costly infrastrucutre are minimized. The heat energy can be used to provide e.g. hot water for domestic use and the cold for cooling down e.g. the building. The compressed air is stored in commercial pressure tanks which is a durable and inexpensive solution to store electricity.


Our highly efficient tri-generation energy storage system aims for an electrical round-trip efficiency of 65%* while extracting heat and cold with a combined COP of 4.6*


* current estimate


Excess electricity is used to fill the compressed air electricity storage. The compression generates heat which is stored in the thermal energy storage


During electricity demand the expansion of the air drives a generator and produces cold



Air & water as working fluids

High combined efficiency

65% electrical efficiency

COP of 4.6

High durability

More than 50'000 cycles

Low costs

Electricity storage far below

1 ct/kWhel