How Much Does a Heat Pump Save Vs. Portable Electric Heaters?

You may be surprised how dramatically a heat pump can reduce your winter electric bill when compared to plug-in room heaters.


We’ve all used small electric heaters to take the edge off in a small office, bathroom, or even the kitchen. They’re inexpensive, relatively safe, presuming they turn off automatically when knocked over, and cost nothing to install. 

You may be tempted to just use some of these, rather than absorb the cost of installing an electric heat pump. But you’ll be wasting a lot of money and producing unnecessary carbon pollution.

Heat pumps use every watt more efficiently to produce heat. To illustrate this, let’s do the math. To produce the same heat as a 12,000 Btu heat pump, you’re going to end up running a bunch of small electric heaters.

I’ll use my home’s heat pump as a baseline. It’s a 12,000 Btu unit with a heating HSPF rating of 10. In temperatures down to single digits (Fahrenheit), it operates in heating mode at about 900 watts. That means that each watt produces about 13.3 Btu.

Let’s say we want to produce the same 12,000 Btu using plug-in heaters. Each 1,500 watt device produces 5,100 Btu, so we’re going to need about two and half electric heaters to produce 12,000 Btu. But that’s not the whole story. Because the heat pump is so much more efficient, it’s going to cut our electric consumption to one fourth of the cost to produce the same heat as those portable heaters.

Maybe an easier way to understand this is to look at your electric bill.

A Whopping Waste of Energy

Let’s say your utility just hiked grid power costs to 25 cents for a kilowatt of energy in your region. Using 2.5 electric heaters for a month, 24 hours a day at 1,500 watts each, you would chock up a whopping 2,700 kilowatt hours of energy use per month.

Cost before distribution fees: $684.45

To produce the same 12,000 Btu with a heat pump operating 24/7 would require 648 kilowatt hours of energy, at a total cost of $164.27 (before other fees). That’s an almost ridiculous savings of $520.18 per month, or $6,242.16 per year.

Admittedly, this is an extreme scenario, where you’re running heat constantly (probably a very poorly insulated house), but it illustrates why the investment in heat pumps is one of the best “after-the-fact” energy upgrades a homeowner can make. In this scenario, you could easily pay for the installation of two heat pumps in energy savings over a single year.

The real-world numbers are probably a bit more conservative. You’ll have annual maintenance costs to consider for the heat pumps, and your heating needs will only apply in the winter. But here’s the flip side of that caveat: In the summer, your heat pumps typically work even more efficiently at cooling your home, using a little more than half the energy required for heating, replacing inefficient air conditioners.

Electric Heater Myths and Misconceptions

Size Doesn’t Matter. Electric heaters only produce their rated output, no matter how big or small they are. A big 1500-watt unit produces the same heat as a small 1500-watt unit.

Wiring Has Limits. The reason most electric heaters only hit 1500 watts is because a 15 amp circuit (typical in most homes) can only handle 1800 watts. If you plug anything else into that circuit, you trigger the breaker. The heater alone uses 12.5 of those 15 amps.ext