KRYOGRID

Resume

KRYOGRID is a comprehensive energy system that in principle includes HVAC technology (heating, cooling and ventilation of a building) in combination with high-capacity energy storage in the form of heat and liquefied air/nitrogen.

The proposed system includes an innovative liquid air engine that uses various types of energy for its own propulsion. Thanks to a balanced system of energy consumption, production and storage (either in the form of heat or in the form of liquefied air/nitrogen), KRYOGRID offers flexible local energy solutions for buildings, including possible profits based on co-production of cryofluids or electricity.

KRYOGRID will enable more efficient use of decentralized energy sources and optimization or overall reduction of local energy consumption for heating and cooling.

With the KRYOGRID system, we can meet our energy needs more cleanly, efficiently and economically.

Working principle

The basis of the heat or cold supply system is a highly efficient air compressor and two water tanks used to accumulate heat or cold. The air compressor is driven by an innovative engine that uses the expansion of liquefied air during its reheating. The air source is mainly waste air from the building.

The system can be set to two basic modes using valves: summer, when the water tank inside the building is cooled and the heat removed from it is stored in a water tank outside the building, and winter, when, on the contrary, heat is pumped from the external water tank and supplied to the internal water tank. In both modes, the exhaust air from the building serves as a flow medium. Before entering the compressor, the air first bubbles through a layer of water in one of the water tanks (depending on the mode), which saturates it with water vapor. It is then compressed in the compressor, which heats it. The compression heat is transferred to the water tank that is heated according to the operating mode via a heat exchanger. The cooled compressed air is fed into the condensate separator and then compressed to high pressure by means of a pressure intensifier. The resulting compression heat is again transferred to the heated water tank.

The high-pressure air, freed from water condensate, is fed into the liquefier. The liquefied air is stored in insulated containers and reused as a working medium to drive the motor, which forms the drive unit of the air compressor. The heat required to reheat the liquefied air and perform the necessary work by means of the motor is obtained, for example, by electric heating during times of cheap electricity prices from the grid or a local source (photovoltaics, wind power plant), by heating using fuel combustion (phytomas, biomethane, bioethanol), or by heating using a thermosolar or geothermal collector.

The system can be supplemented with an electric generator, also driven by a liquefied air motor. By connecting an electric generator, it is possible to supply electrical energy to the grid in the event of sufficient supply of liquefied air and high electricity prices. Furthermore, the liquefied air can be further processed and used, for example, to produce liquefied nitrogen, which can be supplied to local consumers.