Madeline Talebi

Water heating is one of the largest end-uses of natural gas in California, with a significant potential for increased gas savings and decarbonization using fuel-fired heat pump technology. Manufacturers have developed Gas Absorption Heat Pump (GAHP) systems that have entered the market following small-scale and pilot testing, but there is limited part load and transient system performance data that is publicly available for these units. Advantages of GAHP systems include significant reductions (~30%) in gas consumption relative to condensing technologies, which translates to lower utility bills, reduced emissions, zero GWP refrigerant, low electrical grid demand, and retrofit capability to existing underserved multifamily facilities.

The main purpose of this GAHP laboratory testing was to develop steady-state and dynamic performance curves that can be used with the newly developed air-cooled EnergyPlus GAHP model. Understanding both the steady state and transient part load can be useful in sizing the GAHP unit(s) relative to the load and helps to determine the need for any required backup heat supplies and/or storage.

The presentation of these resultant steady state and dynamic performance curves will supplement GAHP modeling capabilities within EnergyPlus that can be used to project energy savings and emissions reductions, and to evaluate GAHP for multiple applications including multifamily water and space heating, commercial laundromats, and various industrial processes.