US research projects to cut AC energy consumption

The 15 projects selected by Advanced Research Projects Agency-Energy (ARPA-E) – within the Building Energy Efficiency Through Innovative Thermodevices (BEETIT) are developing new approaches and technologies for building cooling equipment and air conditioners.
The 15 projects selected by Advanced Research Projects Agency-Energy (ARPA-E) – within the Building Energy Efficiency Through Innovative Thermodevices (BEETIT) are developing new approaches and technologies for building cooling equipment and air conditioners. These projects – funded USD 30.3 million by the US Department of Energy – aim to improve the energy efficiency of HVAC systems by at least 50% at a cost comparable to current technologies.
- United Technologies Research Center is developing an air-conditioning system that is optimized for use in warm and humid climates. UTRC’s air-conditioning system integrates a liquid drying agent or desiccant and a traditional vapour-compression system. The desiccant reduces the humidity in the air before it is cooled, using less energy. The technology uses a membrane as a barrier between the air and the liquid salt stream allowing only water vapour to pass through and not the salt molecules. If successful, UTRC claims this system would be 50% more efficient than conventional air conditioning.
-  Infinia is developing a compact air conditioner based on the Stirling engine, where a motor with a piston removes heat to the outside atmosphere using helium as a refrigerant. Infinia is using chip cooling technology from the computer industry to make improvements to the heat exchanger and improve system performance.
 -  University of Notre Dame is developing an air-conditioning system with a new fluid comprising CO2 and ionic liquid that will allow CO2 to be used at far lower pressures than is possible currently and will enable use in existing equipment, which could open up a wider air-conditioning market using of CO2.
- University of Maryland  is working in the area of thermoelastic cooling systems that use a solid-state material – an elastic shape memory metal alloy –  as a refrigerant and a solid to solid phase transformation to absorb or release heat.
The other projects concern: membrane dehumidification, energy-efficient building ventilation systems, magnetic refrigeration, cascade reverse osmosis air-conditioning system, innovative miniaturized heat pumps for buildings, phononic heat pump, high efficiency adsorption chiller, helium-based soundwave chiller, high-efficiency solid state cooling technologies, compact solid state cooling systems, membrane-based absorption refrigeration systems.