Chillers, Hydro-Fluoro-Olefins (HFOs), HFC-134a, Low GWP, TEWI
The performance of XP10, a new refrigerant with a reduced GWP, in a centrifugal chiller designed for HFC-134a with a cooling capacity of 1969.44 kW (560 tons) was measured under full and part load conditions and compared to performance with HFC-134a. Measured chiller energy efficiencies with XP10 were comparable to those with HFC- 134a. They resulted in 0.6% higher energy consumption for XP10 when integrated over a representative profile of partial loads as described by AHRI Standard 550/590. Based on the measured chiller performance, XP10 could be considered a near drop-in replacement for HFC-134a in centrifugal chillers. It could replace HFC-134a in existing chillers or enable optimized new chiller designs without extensive equipment and no flammability code modifications. The Total Equivalent Warming Impact (TEWI) of a chiller with XP10 was estimated under representative scenarios and compared to TEWI with HFC-134a. Use of XP10 could significantly reduce chiller global warming impact relative to HFC-134a, when chiller refrigerant losses are unavoidably high or when electricity is generated with low GHG emissions. XP10 has the potential to be a more environmentally sustainable future option for medium pressure centrifugal chillers.