The 5th working meeting of IEA HPT Annex 49 was held at the National Institute of Standards and Technologies (NIST) in Gaithersburg, Maryland in the United States from Wednesday, Nov. 7 to Friday, Nov. 9. The meeting was attended by experts of the seven countries AT, CH, DE, EE, NO, SE and the USA.

The meeting was dedicated to the presentation and discussion of the current state of the national project contributions of the participating countries in Annex 49. As introduction, the research departments and projects at NIST and the research programme of the US Department of Energy on heat pumps and high performance buildings was presented. Besides the current results in the research project, also the implementation of nZEB on the national level were presented, since from the deadline of January 1, 2019, nZEB requirements are introduced in EU member states for all new public buildings.

Moreover, the coordination of work and the work planning as well as the deliverables of the Annex task on the heat pump integration in Task 2, the monitoring in Task 3 and the design and control in Task 4 were discussed and related to current developments in the national project contributions to the Annex 49. Furthermore, a common simulation study has been updated and methodologies to compare nZEB ambition level in the different countries have been discussed.

The meeting was accompanied by visits and technical tours to NIST and the University of Maryland.
At NIST, the intelligent building agents lab and the testing facilities for refrigerant testing and HVAC component testing have been visited, and a tour in the Net Zero Energy Residential Testing Facility (NZERTF) for the testing of dedicated Net Zero Energy Home Equipment has been offered.
At the University of Maryland, the lab for Refrigerant Flammability Experiments at the Fire Protection Department has been visited and the elastocaloric materials research at the Materials Engineering Department has been presented.
At the Center for Environmental Energy Engineering (CEEE) participants have been introduced to recent developments in heat exchangers and the roving comforter (RoCo) personal cooling device and software developments for heat exchanger design and refrigerant cycle calculation and design have been presented and demonstrated.

Photo above:
Participants of IEA HPT Annex 49 under the Newton apple tree at NIST , a direct descendant of the apple tree, which inspired Isaac Newton to his theory of gravitational forces.