The US National Team of HPT TCP arranged an interesting workshop at NIST, Gaithersburg in US on November 1 focusing on the latest news covering market, policy and research. Melissa Lapsa talked about the market development in the US and told that the market for heat pumps and AC has steadily grown since 2008. Interesting to note is the growing demand for ground source heat pumps. Heat pumps are installed in 40% of the new built houses in US. Half of the number of heat pumps sold goes to new homes and heat pumps represent about 10-15% of the whole heating market.
Several presentations during the day covered mapping and application of low GWP refrigerants. One barrier for implementation is the existing standards and building codes for A2L refrigerants (lightly flammable). Furthermore, there is a need to communicate and educate stakeholders about the environmental advantages with new refrigerants. AHRI (American Heating and Refrigeration Institute) with 320 members are working with the development of standards and certification programs. There is ongoing R&D including to support implementation of low GWP refrigerants including new models, increased knowledge about leakage and recommendation for charge for different types of flammable refrigerants to minimize risk. EPA (Environmental Protection Agency) authorizes the use of refrigerants and DOE (Deportment of Energy) is supporting R&D for implementation of new technoloies and new refrigerants.
Prof Eckard Groll from Purdue University made a presentation about ongoing R&D activities. Among other things he informed about hybrid-drive variable speed compressors, which is a retrofit solution to turn single capacity heat pumps to run at part load. The largest challenge is to ensure enough lubrication and a scroll compressor is more sensitive. Another topic was refrigerant injection compression by the application of economizer and several injection points. The theoretical improvement is 40 % .
Other presentations during the day were about the latest development for new innovative refrigeration technologies like elastocaloric refrigeration, magnetocaloric refrigeration and electrochemical compression.
All the presentations given during the day can be found here.