3 ms·
This appears to be the minimum for geothermal. The vast majority of heat pump installs would be air source, and while these can often get 3+ it’s highly depende
by ericpauley 4y ago
This appears to be the minimum for geothermal. The vast majority of heat pump installs would be air source, and while these can often get 3+ it’s highly dependent on climate and local grid efficiency.
It also depends on local prices. In Madison, WI our implied (not actual) electric grid efficiency based on prices is under 20%.
- xxpor 4y agoThe energy.gov page has more details, it's 3.3 for air source at 47 deg F and a reasonable size: https://www.energy.gov/eere/femp/incorporate-minimum-efficiency-requirements-heating-and-cooling-products-federal#airsource https://www.energy.gov/eere/femp/incorporate-minimum-efficie...