Radiation Defrosting Technique

Oak Ridge National Laboratory will develop a novel, cost-effective and energy-efficient approach to enhance the defrost process for cold climate heat pumps and commercial refrigeration systems utilizing radiations.

Frost formation presents a challenge for both the heat pump and the refrigeration industry, in both residential and commercial applications. Frost buildup increases pressure drop (fan power) and decreases heat transfer, due to the reduced air flow area and thermal conductivity when compared to the base heat exchanger material.

The project team will evaluate the potential of radiation-based defrost (microwaves, UV, visible) processes for deployment in cold climate heat pumps and commercial refrigeration. Radiation defrost can provide a novel approach with significantly lower energy requirements, and can be accomplished continuously or intermittently. To evaluate impact, the team will characterize frost growth on various surfaces, as well as analyze various radiation sources for appropriateness for the proposed application.

Project Impact

The efficiency degradation due to frost growth, and the energy required to defrost, can account for 15-25% of the annual electric energy consumption by heat pumps. The development of effective frost mitigation and defrost technology can lead to more than 200TBtu/year of U.S. primary energy savings.