Five U.S. companies that are developing CO2 (R744)-based heat pumps are among the 25 organizations in 17 states selected by the U.S. Department of Energy (DOE) to receive $38.8 million in funding to research and develop high-impact building technologies, including next-generation retrofits for the building envelope, lighting, and heating, ventilation and air conditioning (HVAC).
One of the CO2 projects also employs propane (R290); two projects involving only propane are also being funded by the DOE.
The research is aimed at “decarbonizing, reducing peak demand on the electric grid, enhancing resilience, and lowering energy costs,” said the DOE in the announcement on September 17. Funding comes from the DOE’s Buildings Energy Efficiency Frontiers & Innovation Technologies (BENEFIT) opportunity.
The companies developing CO2 heat pumps include:
Ecotope, Seattle, Washington, will demonstrate the viability of a simple plug-and-play approach to replacing commercial fossil fuel boilers with electric heat pumps using CO2 and R290 refrigerants. The project will demonstrate the replacement of fossil fuel boilers in two low-and-moderate income (LMI) affordable multifamily buildings. These packaged or “monoblock” air-to-water heat pumps provide heating, cooling, and service hot water from a single fully packaged product utilizing a single electrical circuit. The award amount is $1.3 million. Ecotope published a white paper in January called “Roadmap for Overcoming Barriers to Using Natural Refrigerants in the United States.”
NETenergy, Chicago, Illinois, seeks to develop, model, validate and test a high-efficiency closed-loop hybrid CO2 heat pump-thermochemical system that can replace existing gas boilers without replacing the existing hydronic distribution system. The proposed concept avoids costly replacement of hydronic distribution systems and offers manufacturers a drop-in replacement for the central gas boiler system in multifamily, commercial buildings, and district systems, said the DOE. The award amount is $2 million.
GTI Energy, Des Plaines, Illinois is designing and developing a novel oil-free CO2 compressor/expander. The success of the project can significantly advance CO2 heat pump technology and in turn, improve market adoption of natural refrigerant equipment, said the DOE. The award amount is $2 million.
Effecterra, Reno, Nevada, will build a working proof-of-concept 25TR commercial rooftop unit (RTU) heat pump that uses a CO2 refrigerant. This demonstration highlights the market application potential for ultra-low global warming CO2 refrigerants in RTU heat pumps, which can exceed the performance operation of the current best-in-class commercially available equipment, said the DOE. The award amount is $1.2 million.
Harvest Thermal, Kensington, California is developing a market-ready integrated packaged CO2 refrigerant heat pump system that provides a high-performance combined heating and hot water system at a lower cost for residential applications, said the DOE. The award amount is $2 million.
R290 projects
The two R290 projects receiving funding are:
Evari, Peterborough, New Hampshire, will develop commercially viable and cost-effective residential cold climate heat pumps that use propane as its working fluid, said the DOE. This project uses novel microturbine compressor technology that yields a coefficient of performance twice that of the current best-in-class products in the coldest conditions, the agency added. The award amount is $1.7 million.
The AHRI, based in Arlington, Virginia, has been selected to receive $2.5 million from the U.S. Department of Energy (DOE) as part of a collaborative effort to address “performance and safety concerns” for implementing air-to-water heat pumps in the U.S. market that use flammable (A3) refrigerants such as propane. The research will support the efforts of ASHRAE to evaluate a proposal to raise the charge limit of R290 in its safety standards for residential outdoor (indirect) heat pumps and air conditioners in the U.S. to 4.9kg (10.9lbs), comparable to what is allowed in Europe.
In addition, Syracuse University Center of Excellence in Environmental and Energy Systems, Hydronic Shell Technologies and Cycle Retrotech will collaborate to develop and demonstrate the patented Hydronic Shell (HS) retrofit solution. The HydroBox addresses challenges of building retrofits by delivering heating, cooling and ventilation through hydronic piping and ventilation ductwork, efficiently integrated into a building’s facade with minimal disruption to tenants, the DOE said. The award amount is $1.9 million.
