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Calculator · Updated August 2026
Heat pump and solar load calculator
A heat pump can double your electricity use — in the season solar produces least.
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The calculator
What would a heat pump add to your electric load?
A rough estimate from square footage and climate. A Manual J load calculation is the real answer and any competent installer will do one.
This is an estimate, not a savings guarantee.
It uses published utility rates, NREL regional sun data and a standard system derate. It does not know your roof orientation, your shading, your usage pattern or what your utility will charge next year. No solar company can honestly guarantee savings, and any that does is describing a model rather than making a promise.
Electrifying heat changes your solar sizing completely
A heat pump can double a household's annual electricity consumption, and it does it in winter — exactly when a solar array produces least. In the Northeast, December production is often a third of June production while heating load peaks. An array sized to cover annual heat pump consumption will export heavily in summer and import heavily in winter.
That is fine where net metering is 1:1 at retail, because the summer surplus banks against the winter deficit. It is expensive where export credit is well below retail, because you sell low in July and buy high in January.
So the order of operations matters
If you are considering both, decide on the heat pump first and size the solar to the post-heat-pump load. Sizing to today's usage and adding panels later costs more per watt, and some utilities cap system size at a percentage of historical usage — which means your pre-heat-pump usage can limit the array you are allowed to build.
Whether it saves money depends on what you burn now
Against electric resistance heat, a heat pump typically uses around a third of the electricity, and the saving is unambiguous. Against fuel oil or propane it usually wins on running cost. Against natural gas it frequently does not at current prices, and honest advice here depends on your gas rate and your electricity rate, not on a general claim.
What does hold in every case: a heat pump moves load from a fuel you cannot generate to one you can. That is an argument about exposure and control rather than about immediate savings.
Cold-climate performance
Modern cold-climate heat pumps maintain useful output well below freezing, but efficiency falls as temperature does, and most installations retain backup heat for the coldest days. That backup is often electric resistance, which is where winter bills spike. Ask what the backup is and at what outdoor temperature it engages.
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Who you would be working with
SolarAmerica
We design your system and manage the project; installation is performed by vetted licensed partners in your area. SolarAmerica is not itself the installing contractor.
Questions
The things people actually ask
How much electricity does a heat pump use?
Roughly 3.6 kWh per square foot per year in a moderate climate, adjusted for how cold your winters are. A 2,000 square foot home in Pennsylvania lands around 7,200 kWh. A Manual J calculation is the accurate answer.
Will solar cover a heat pump?
Annually, often yes with 5–6 kW of additional array. Seasonally, no — production is lowest when heating load is highest, so it depends on your net metering structure carrying summer surplus into winter.
Is a heat pump cheaper than gas?
Frequently not at current gas prices. It is usually cheaper than oil, propane and electric resistance. The honest answer depends on your specific gas and electric rates.
Should I size solar before or after a heat pump?
After, or at least accounting for it. Some utilities cap system size at a percentage of historical usage, so installing solar first can limit the array you are permitted.
Get the number for your actual roof
About 60 seconds. No cost, no obligation, and we will tell you if solar does not make sense for your home.
Ranked #1 by Solar Power World · 20,000+ installations · Licensed installers