Solar panels can power a heat pump. Here’s how many solar panels you need to cover a heat pump’s power consumption. Additionally, you’ll get to know the cost of installing the solar panels as well as the heat pump.
Quick answer: Yes, you need 17 solar panels to run an average 3-ton heat pump. Depending on the unit size and efficiency of your heat pump, you will need anywhere between 5 to 32 solar panels. Check the table below to see how many solar panels you need to run your heat pump.
Stick out! In this article, we’re going to cover
- How we got to these results
- Tables with the exact number of solar panels you need to install to run your heat pump
- How much installing the solar panels and the heat pump will cost you
So, let’s start!
How much Power does a Heat Pump consume?
Heat pumps use anywhere between 545W and 4,286W of power depending on the unit size and SEER rating.
SEER is the Seasonal Energy Efficiency Rating. It describes how many BTUs (British Thermal Units) you get per Watt of input power.
Don’t worry, we’re not going into any calculations. Check the article on how to calculate heat pump power usage if you are interested in how to get to these results.
You can look up the SEER value of your heat pump in the specifications (a sticker somewhere on your heat pump, or just google it).
If you are too lazy to look up, then just assume your heat pump has a SEER of 16 or 18. That’s a reasonable assumption for most modern heat pumps.
In this article, I am going to hide the difficult stuff from you and just present you the numbers.
To find out how many solar panels you need to power a heat pump, we have to first find out how much electric energy a heat pump uses per year.
How much energy does a heat pump consume in a year?
A heat pump runs an average of 5475 hours a year. Small and efficient units use 2,984kWh and large, inefficient units use up to 14,076kWh a year.
The energy consumption of your heat pump (moderately sized and medium efficiency) is likely somewhere in the middle, between 6,500kWh and 8,000kWh.
Depending on your heat pump unit’s size and efficiency, this causes the following energy requirements:
| Unit size | 14 SEER | 16 SEER | 18 SEER | 20 SEER | 22 SEER |
|---|---|---|---|---|---|
| 1.0 tons | 4,692 kWh | 4,106 kWh | 3,652 kWh | 3,285 kWh | 2,984 kWh |
| 1.5 tons | 7,041 kWh | 6,159 kWh | 5,475 kWh | 4,928 kWh | 4,479 kWh |
| 2.0 tons | 9,384 kWh | 8,213 kWh | 7,298 kWh | 6,570 kWh | 5,973 kWh |
| 2.5 tons | 11,733 kWh | 10,266 kWh | 9,127 kWh | 8,213 kWh | 7,468 kWh |
| 3.0 tons | 14,076 kWh | 12,319 kWh | 10,950 kWh | 9,855 kWh | 8,957 kWh |
| 3.5 tons | 16,425 kWh | 14,372 kWh | 12,773 kWh | 11,498 kWh | 10,452 kWh |
| 4.0 tons | 18,774 kWh | 16,425 kWh | 14,602 kWh | 13,140 kWh | 11,946 kWh |
| 4.5 tons | 21,117 kWh | 18,478 kWh | 16,425 kWh | 14,783 kWh | 13,441 kWh |
| 5.0 tons | 23,466 kWh | 20,531 kWh | 18,248 kWh | 16,425 kWh | 14,930 kWh |
How much Power do Solar Panels produce?
Now we know how much energy a heat pump requires in a year. The only thing left to do is to find out how much energy an average solar panel produces in a given year.
I’ve already crunched the numbers in this article: Can solar panels heat a house?
Here’s the result:
An average solar panel generates 1.8kWh (Kilo-Watt hours) of energy per day. In 1 year, that’s 657kWh of electricity.
How many Solar Panels do you need to run a Heat Pump?
Now that we know how much power a heat pump uses, and how much power an average solar panel generates, we can calculate the number of solar panels you are going to need to power your heat pump.
The table below lists the required number of solar panels for different unit sizes and SEER ratings:
| Unit size | 14 SEER | 16 SEER | 18 SEER | 20 SEER | 22 SEER |
|---|---|---|---|---|---|
| 1.0 tons | 7 panels | 6 panels | 6 panels | 5 panels | 5 panels |
| 1.5 tons | 11 panels | 9 panels | 8 panels | 8 panels | 7 panels |
| 2.0 tons | 14 panels | 13 panels | 11 panels | 10 panels | 9 panels |
| 2.5 tons | 18 panels | 16 panels | 14 panels | 13 panels | 11 panels |
| 3.0 tons | 21 panels | 19 panels | 17 panels | 15 panels | 14 panels |
| 3.5 tons | 25 panels | 22 panels | 19 panels | 18 panels | 16 panels |
| 4.0 tons | 29 panels | 25 panels | 22 panels | 20 panels | 18 panels |
| 4.5 tons | 32 panels | 28 panels | 25 panels | 23 panels | 20 panels |
| 5.0 tons | 36 panels | 31 panels | 28 panels | 25 panels | 23 panels |
How much is the installation cost of solar panels for a heat pump?
“The average total cost to install a residential system for solar panels before tax credits or rebates is comparable to the price tag on a new car.”
Man, that’s a vague statement. Is it as expensive as a 10-year old used Toyota, or is it a new Benz? I hate meaningless statements. So, again, I crunched the numbers for you.
The installation cost of solar panels is between $2.20 and $2.80 per Watt.
One heat pump uses between 545W (22 SEER) and 857W (14 SEER) per ton.
To cover the cost of heat pumps, you will need to install between $1362.50 and $2142.5 worth of solar panels per ton of heating capacity.
This assumption leads to the following results:
| Heat pump size | Minimum solar panel system cost | Maximum solar panel system cost |
|---|---|---|
| 1 ton | $1,362.50 | $2,142.50 |
| 2 tons | $2,725.00 | $4,285.00 |
| 3 tons | $4,087.50 | $6,427.50 |
| 4 tons | $5,450.00 | $8,570.00 |
| 5 tons | $6,812.50 | $10,712.50 |
Additionally, you can add 30-50% on top for the installation. The exact installation cost is hard to tell. You should get your phone and call 2-3 companies to get a quote! (Always tell them you’ve already called their competitors, and they are cheaper!)
Anyways, installing solar panels is an expensive investment. Nevertheless, solar panels pay for themselves after 7 years. That’s a good return on investment here. After 7 years, you are profiting. I think it’s worth it.
Are Solar Panels compatible with a Heat Pump?
Yes, solar panels are compatible with a heat pump. Solar panels connect directly to your neighborhood’s electric grid and make use of net metering. Net metering is when you feed power into the electric grid and you are compensated for it on your electric bill.
This means the power you generate in the summertime when there’s lots of sunshine pays for your heating in the winter!
If you are using solar panels off-grid, you should get a large battery to store as much energy as possible.
However, in this situation, I think solar panels and heat pumps are not the right way to heat. Rather you should stick to wood-burning stoves. Heating using a stove is objectively the most cost-effective way to heat a room (backed up by data).
Solar Panels and Heat Pumps: Conclusion
Combining a heat pump with solar panels is a great way to heat a house!
Especially since the heat pump acts as leverage (it has an efficiency bigger than one), meaning it moves more heat into your home than it consumes. This reduces the number of solar panels you are going to need to heat your home as compared to other heating methods that rely on electricity.
You had a great idea and you’ve got my approval!
(Which is worth something, considering I am very critical when it comes to fancy heating methods)