Open Competition 3 - Chemistry and Materials
Active Magnetic Regenerator Refrigerator
Design, build, and test a magnetic refrigerator that is energy efficient, cost effective, and environmentally safe.
Sponsor: Astronautics Corporation of America4115 N. Teutonia Avenue
Milwaukee, WI 53209
Current refrigeration systems use century-old vapor compression technology, and only marginal improvements in efficiency are possible for this mature technology. Astronautics Corporation of America will design, build, and test a magnetic refrigerator that is energy efficient, cost effective, and environmentally safe. Magnetic refrigeration-based appliances also will run more quietly and weigh less than those with current refrigeration systems. This technology could be used in a wide variety of products with cooling loads ranging from10 to 5,000 watts including refrigerators, dehumidifiers, and air conditioners. A key feature of this technology will be a high-performance active magnetic regenerator (AMR) matrix made of advanced magnetocaloric materials (MCMs), such as gadolinium metal and gadolinium alloys. Segments of a wheel carrying the matrix rotate into a magnetic field generated by a permanent magnet, alternately magnetizing and demagnetizing the MCM refrigerant, thus raising and lowering its temperature. Rotating the wheel while pumping a fluid such as water through the matrix and through heat exchangers establishes the refrigeration cycle. The aim of this three-year project is to validate this rotary design incorporating an advanced AMR matrix for a magnetic refrigerator. Developing a high-performance matrix is the primary risk. This task requires finding suitable materials; fabricating these materials into a suitable geometry and joining the materials; and laminating the plates into a strong, monolithic matrix that has minimal volume and allows optimal fluid flow with low pumping power. Ceramatec (Salt Lake City, UT) will be subcontracted to develop fabrication methods for constructing AMRs from brittle materials, and Ames Laboratory (Ames, IA) will be subcontracted to characterize magnetocaloric materials. Astronautics cannot invest at the rate needed to bring this technology rapidly to market. Refrigeration and air conditioning companies find the technical risks to be too high, and the funds needed exceed their R&D budgets. ATP funding would accelerate development and reduce time to market by three to five years. Current refrigeration systems account for 25 percent of residential electricity usage and over 15 percent of commercial electric demand. When fully commercialized, magnetic refrigeration could reduce residential energy usage by $5 billion annually.