3 ms·
>heat pumps are (effectively) more than 100% efficient The CoP of a heat pump is greatly dependent on the difference in temperature potential of the source and
by DINKDINK 9y ago
>heat pumps are (effectively) more than 100% efficient
The CoP of a heat pump is greatly dependent on the difference in temperature potential of the source and sink. If it's extremely cold outside, it's very hard to pump heat from colder air into a house. When the temperature potential between the two reservoirs is equal, sure the CoP beats out electric heating but when it's high (When your house is warm and the outside is below freezing) its extremely poor.
http://alliedthermaldesigns.com/wp-content/uploads/2012/10/TEC-Perf-COP-27C-12785.jpg http://alliedthermaldesigns.com/wp-content/uploads/2012/10/T...
- wlesieutre 9y agoVery true for air source heat pumps. Ground source is still an option for colder areas, but that's a much more involved installation.
- maxerickson 9y agoYour link is for Peltier coolers. This government study of an air source heat pump maintained a real world COP of ~3 in Connecticut: https://www.nrel.gov/docs/fy13osti/56393.pdf https://www.nrel.gov/docs/fy13osti/56393.pdf It would be pretty bad to design a heat pump that dropped much below 1, better to just install a big resistive element.
- DINKDINK 9y agoCool data. Appears the CoP vs outdoor temp plots are on page 14. Since the data doesn't provide temperature delta between the source and sink, you'd need to assume that the pump met the heat delivery requirements.