Back to Search Start Over

Detailed evaluation of electric demand load shifting potential of heat pump water heaters in a hot humid climate.

Authors :
Fenaughty, Karen
Parker, Danny S.
Butzbaugh, Joshua
Colon, Carlos
Source :
Science & Technology for the Built Environment. 2023, Vol. 29 Issue 9, p905-926. 22p.
Publication Year :
2023

Abstract

Heat pump water heaters (HPWH) are a proven method of reducing water heating energy use over prevailing electric resistance systems (ERWH). Both technologies lend themselves to enhanced control for peak load reduction. Laboratory tests were conducted in Central Florida using the CTA-2045 standard to evaluate load shifting strategies with connected water heaters. Four HPWHs from three manufacturers, including two different tank volumes, were tested alongside an ERWH in a garage-like environment. Tests aimed to shift energy use away from utility peak load periods to off-peak times when excess renewable energy resources are often available. Two load-shifting strategies were shown effective, Shed and Critical Peak, with variation by manufacturer. Beyond draw volume, other factors influenced HPWH load shifting: Florida winter conditions, which increase the energy used per draw, provided the greatest challenges to complete load shift. Inlet water temperature had a large impact on the success of load reduction. Ground temperatures in which water pipes were buried largely determined inlet water temperatures. HPWH efficiency setting: Heat pump water heaters often default to a "hybrid" mode that may use some electric resistance heat to minimize risk of running out of hot water. Operational mode can impact load shifting potential. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
23744731
Volume :
29
Issue :
9
Database :
Academic Search Index
Journal :
Science & Technology for the Built Environment
Publication Type :
Academic Journal
Accession number :
173436931
Full Text :
https://doi.org/10.1080/23744731.2023.2261808