Propane vs Electric Space Heater: Which is better?

Should you get a propane heater or an electric heater? Which one is better for you? In this article, I am going to introduce you to all the relevant differences between propane and electric heaters!

After reading this article, you will know exactly in which case you should prefer propane heaters over electric heaters and vice versa.

It’s actually quite simple.

Quick answer: Propane heaters are better than electric space heaters for rooms without a heat source or access to electricity. They are cheaper to run and can produce more heat. Meanwhile, electric space heaters don’t need refills and are usually safer.

Propane vs Electric space heaters: Summary of important differences

Running cost$35.28 (per million BTU)$87.98 (per million BTU)
Heat outputup to 30,000 BTU/hup to 5,100 BTU/h
Indoor safetyOKbetween OK (infrared heaters) and very safe (oil-filled radiators)
Running time14 daysindefinitely

Now that you know the key differences, let’s have a look at each of those in a bit more detail:

Propane heaters work without electricity

Let’s start with the simplest one first. Does the space you want to heat have access to electricity?

If the answer here is “no”, then your only choice is to use a heater with an independent energy source. In this case, it’s the propane heater.

Propane heaters are the best choice for heating off-grid spaces, such as cabins, RVs, or off-grid garages.

Also, propane heaters are a great backup heat source for electricity outages.

If you have access to electricity, then you can theoretically use either a propane heater or an electric heater.

Because even when you have access to electricity, electric space heaters aren’t necessarily the better choice.

Now that we covered the energy source, let’s check your heat requirements.

Which heater outputs more heat?

In general, electric space heaters produce up to 1,500W of heat. At least, that’s the case for 120V US heaters. In the UK and Europe, space heaters run on 230V outlets and can, therefore, draw more power (up to >3,000W).

Most electric space heaters, however, are 1,500W models, so that’s our baseline for the comparison.

The heat output of propane heaters is measured in BTU(British Thermal Units) per hour. 

1 BTU/h = 0.293W

You can convert from BTU/h to Watts by multiplying with 0.293. Conversely, you can convert from Watts to BTU/h by dividing by 0.293.

So, 1,500W corresponds to

1,500W / 0.293 ≈ 5,100 BTU/h

This means, an average electric space heater produces up to 5,100 BTU of heat per hour.

Indoor propane heaters can easily produce more heat than that.

A basic portable propane heater produces 9,000 BTU/h of heat. A slightly larger version produces 18,000 BTU/h.

The largest indoor propane heaters can output up to 30,000 BTU/h. There are even stronger models, but these are usually outdoor heaters such as patio heaters or industrial-grade torpedo heaters.

Room sizes you can heat with propane vs electric heaters

A common rule of thumb is that one square foot of your room needs 20 BTU/h of heating power.

So, let’s have a look at different room sizes and check whether propane heaters and electric heaters can heat them.

For this, I’ve assumed that an electric space heater produces 5,100 BTU/h of heat, whereas you can find propane heaters with up to 30,000 BTU/h of heating power.

Room size (in sq. ft.)Can propane heaters heat it?Can electric space heater heat it?
100 sq. ft.YesYes
150 sq. ft.YesYes
200 sq. ft.YesYes
250 sq. ft.YesYes
300 sq. ft.YesNo
350 sq. ft.YesNo
400 sq. ft.YesNo
450 sq. ft.YesNo
500 sq. ft.YesNo
600 sq. ft.YesNo
700 sq. ft.YesNo
800 sq. ft.YesNo
900 sq. ft.YesNo
1000 sq. ft.YesNo
1500 sq. ft.YesNo
2000 sq. ft.NoNo
3000 sq. ft.NoNo

Yes, the table above shows really large room sizes. Very few people have rooms 1000 sq. ft. and higher. But this gets the point across that you can find a propane heater for almost any common room size.

Heating rooms over 300 sq. ft. with electric space heaters is possible. However, they won’t be able to get you comfortably warm.

That’s why propane heaters are much better suited for heating large spaces.

Propane vs Electric space heater running cost comparison

Let’s have a look at the running cost of propane and electric space heaters. Which one is cheaper?

Electric space heaters

Electric space heaters are expensive to run. A 1,500W space heater consumes 1,500Wh (or 1.5kWh) of energy per hour.

With an average electricity rate in the US of 14 cents per kWh, running an electric space heater for one hour costs 21 cents.

However, due to inflation, these prices are rising quickly. The 14 cents per kWh are the latest official electricity rate. However, I suspect that running a space heater for one hour with the current prices can cost over 40 cents.

In the UK and Europe, it’s even worse. There a space heater hour is closer to 60 cents.

Propane heater

Running a propane heater is significantly cheaper than running an electric space heater. The cost of one million BTUs of heat energy from propane is $35.28.

This makes propane the second most cost-effective heat source after wood.

Meanwhile, the same amount of heat generated with electricity costs $87.98.

Accordingly, propane heat costs 60% less than electric heat.

That’s a significant advantage of heating using propane.

Please note that this calculation does not factor in the price of the propane tank or the cost to drive to a propane refill location.

But similarly, the cost of electricity does not factor in the price of installing wall outlets or building your home’s electric circuits in the first place.

It is a purely “cost per heat”-based comparison. You could account for all the minute details, but the result would be the same: Propane is always cheaper than electricity.

How long does a propane heater last?

So far, we’ve seen that propane heaters are both cheaper to run and hotter than electric space heaters.

One of the biggest disadvantages of propane heaters is, however, the energy source itself.

You will have to refill the propane.

Let’s assume that you run a propane heater on 5,100 BTU per hour. This is the same amount of heat that a 1,500W electric space heater outputs.

On a 100lb propane tank (which contains a total of 1,727,520 BTU) you can run such a propane heater for roughly 339 hours. That’s more than 14 days continuously!

Usually, you don’t run a propane heater continuously. Heating for 12 hours a day is more than enough.

So, you can run a propane heater for more than a month on a large 100lb tank.

Of course, the bigger the tank size, the longer it will last.

To conclude this: Yes, it can be annoying to refill your propane heater.

But you won’t have to do get a refill too often. Propane gas contains a lot of heat energy. So, even a small tank will last you for a while. Especially, when it’s not your main heat source.

Is electric heat safer than propane?

Which is safer? Electric or propane heat? To answer this question, we have to distinguish between two types of common electric heaters.

Here’s the quick answer:

The safest space heaters are electric oil-filled radiators. They don’t have exposed heating elements and only moderate surface temperatures. Oil-filled radiators are child and pet-safe.

Contrary, propane heaters and electric infrared heaters have exposed heating elements and can produce very hot temperatures.

The space right in front of propane and infrared heaters can get hot enough to burn plastic.

If your space heater has to be very safe, then propane is not an option for you. But also electric infrared heaters are not very safe.

I’d say that as long as you use your heater reasonably, nothing can happen. I am running my infrared heater almost every day, and nothing ever happened.

You really have to challenge your fate and place sensitive objects right in front of your propane or infrared heater to risk a fire.

As long as no kids or pets are around, all space heaters are safe. But as soon as dumb people (throwing toothpicks into the heating elements) are around, no space heater is safe.

So, it’s all about proper and reasonable usage.

Technically, electric space heaters can be safer than propane heaters as they usually have a built-in thermostat that keeps the heater at moderate temperatures.

When to use which heater? (Questions to help you decide)

I’ve tried to lay out this article in a way that helps you make the decision!

Here are some decision-guiding questions:

Do you have access to electricity? If not, then get a propane heater. Else, continue with the next question.

Is your living space larger than 300 square feet or do you need a strong heat source? If yes, then get a propane heater. Else, continue.

Do you want to save money (even though you have to refill gas occasionally)? If yes, get a propane heater. Else, continue.

Do you need a very safe space heater? If yes, get an electric oil-filled radiator. Else, get whichever propane or electric heater you prefer.

Recommended products: Best propane and electric space heaters

If you want to get an electric space heater, then I highly recommend getting this Pelonis oil-filled radiator (click to read my review).

If, on the other hand, you decide for a propane heater, then check out this favorite of mine: Mr. Heater Big Buddy propane heater (click to read my review).

Both are great heaters and will last you a long time! 


Propane heaters are great primary and independent heat sources. They output a lot of heat for just a fraction of the cost of electric heat.

However, propane heaters need occasional tank refills and are not as safe as some electric space heaters (oil-filled radiators).

In general, if you already have a central heat source at home and you just want supplementary heat, then electric space heaters are fine.

But if you want to heat a space that has no heat source and maybe even poor insulation, then propane heaters are your best bet!