Electric space heaters run on electricity, and electricity is not exactly cheap. For sake of the environment as well as your wallet, it makes sense to get the most energy-efficient space heater you can find.
What are the most energy-efficient space heaters?
Well, they are simply units that:
- Provide us with as much heating output as possible.
- For the lowest electricity expenditure.
Now, first of all, we need to be aware that using electricity for heating is not the most cost-effective option. However, it’s by far the most convenient one (safe to use indoors, no gas piping, no installation costs, and so forth).
Here’s what the Department Of Energy says about the effectiveness of electric space heaters:
“Electric space heaters are generally more expensive to operate than combustion space heaters, but they are the only unvented space heaters that are safe to operate inside your home.” (US Department Of Energy On Electric Space Heaters)
If you need to heat up indoor spaces safely and effectively, buying one of the most energy-efficient space heaters makes a whole lot of sense.

To help you out, we have prepared a list of the 5 most energy-efficient electric space heaters, complete with a comparison table and reviews of each heater (and its energy efficiency). You can skip to the whole list of the energy-efficient space heaters here:
Skip To List Of 5 Most Energy Efficient Space Heaters Here
But before you pick your heaters, let’s look at the few key consideration and specifications. We’ll go through some interesting aspects when it comes to electric room heaters and energy efficiency, namely:
- How difficult it actually is to pinpoint exactly which space heater is the most energy-efficient.
- What technologies help increase the energy efficiency of electric space heaters?
- What is the maximum cost you’re likely to pay for a running hour of a space heater (efficient and non-efficient)?
- Wattage and heating coverage area of electric space heaters.
For your understanding, it’s quite useful to go through all these considerations. If you just need to get the most efficient heater, you can skip to the comparison table below.
How To Tell Which Space Heater Is The Most Energy-Efficient?
How to tell if an electric space heater is actually energy efficient?
With a lot of HVAC appliances such as air conditioners, furnaces, and so forth, you can just look at the energy efficiency ratings like SEER, AFUE, HSPF. The most efficient unit is the one with the highest SEER rating, for example.
Unfortunately, there is no such energy-efficient rating for electric space heaters. Most of them have a maximum power input of 1,500W. This pretty much equates to 1,500W or a good 5,000 BTU/hr heating output since electrical energy is converted to heat at nearly 100% efficiency. It costs about $0.20 per hour to run an electric space heater at the full heating output.
The second best thing to look for when checking which unit is energy-efficient is an Energy Star label. Units with the Energy Star label are among the top 10% or 20% of the most energy-efficient units in their category.
However, you won’t find an Energy Star rated electric space heater simply because EPA doesn’t use this label for space heaters:
“EPA does not currently label space heaters as an ENERGY STAR qualified product.” (Energy Star On Space Heaters)
As you can see, figuring out which space heater is the most energy-efficient is not all that easy. Electricity is converted to heat at nearly 100% efficiency in all electric space heaters (no differences there). All you can compare are the input wattage, right?
Now:
It is a fact that some electric space heaters are more energy-efficient than others. What are the mechanisms by which these more efficient electric space heaters conserve energy? Let’s check some of them out:
What Technologies Make Space Heater More Energy Efficient? (Efficiency Boosters)
Electricity cannot be used more effectively for heating. It’s already near 100%; you can’t make it to be more effective.
To make electric space heaters more energy-efficient, you can basically do one thing:
Correlate the heating needs as close as possible with the heater heating output.
You can do that automatically (via thermostat) or manually (via switching between different electricity inputs). Thermostats are rarely in use in the case of electric space heaters; these devices are too small for thermostats to be needed.
Having different temperature settings (or wattage inputs) is very useful if you want to achieve energy-efficient heating. In most cases, electric space heaters have only two settings:
- High setting: 1,500W of electrical input.
- Low setting: 750W of electrical input.
Based on these main settings, energy-efficient electric space heaters can achieve a different number of temperature modes. The #1 Dr Infrared Heater (check the list below) is not the most energy-efficient electric space heater due to its high quality and reliable design; it is so energy efficient precisely because it can offer you ECO auto energy savings mode.
Switching between those you can correlate the heater output exactly to your heating needs, making the space heater burn fewer kilowatt-hours worth of electricity to warm you and the room you’re in.
Other energy-efficiency units may employ technologies that automatically adjust the heating output to the heating needs. These technologies or temperature modes go by different names because every producer just wants a unique name to the eco temperature mode (but basically mean the same thing).
Here are some names used for eco-friendly energy-efficient electric space heater temperature modes:
- Smart ECO mode.
- EcoEnergy mode. Check #3 De’Longhi SlimStyle.
- EcoSmart mode.
- EcoEfficient mode.
Money-saving space heaters use thermostats that adjust the heating output. This prevents you from needlessly wasting electricity.
If you want to pick the most energy-efficient electric space heater, it makes sense to look for these eco-friendly (in translation: energy-saving) temperature modes.
Types Of Electric Space Heaters
Now, ‘electric space heater’ is quite a broad term for a number of different types of space heaters that run on electricity.
In the table below, we have gathered the most energy-efficient space heaters by type as well. As you can see, you can choose between:
- Classic electric space heaters (up to 1,500W units).
- Oil-filled radiator heaters (power by electricity, even have some residual heat effect due to high energy capacity of oil).
- Convection panels (safest to use; have a large area where the generated heat can be easily transferred to the air).
- Wall-mounted electric heaters (great space savers, rather easy to install as well).
- Infrared heaters (these use harmless infrared radiation to heat a person near them).
Each of these subtypes of electric space heaters have their most energy-efficient and least energy-efficient units. You can check the most efficient ones in the table below.
Coverage Area Of Efficient Electric Space Heaters (Depends Solely On Input Wattage)
One deceptive marketing tactic of producers trying to depict their electric space heater as energy efficient is this:
“Our space heater uses 50% less electricity than similar heaters.”,
or
“Our space heater uses only 1p worth of electricity per hour.”
Now, if an electric space heater uses 50% less electricity, it also produces 50% lower heating output. If it uses only 1p ($0.01) electricity per hour, it will only produce 1p worth of heating output (which isn’t a lot).
It is vital to understand that the heating output, and thereby the coverage area, of electric space heaters, depends solemnly on input wattage. The more electricity you will give it, the more heat it will produce.
Here is a reference table with rough estimates of how big an area can electric space heaters cover (for common space heater electricity inputs). Keep in mind that these heaters primarily provide supplemental heating, and are not meant to be used as central heating units:
Heating Input (Wattage): | Supplemental Heating Area: | Central Heating Area: |
400 W | Up to 270 sq ft | 40 sq ft |
500 W | Up to 330 sq ft | 50 sq ft |
750 W | Up to 500 sq ft | 75 sq ft |
1,000 W | Up to 670 sq ft | 100 sq ft |
1,200 W | Up to 800 sq ft | 120 sq ft |
1,500 W | Up to 1,000 sq ft | 150 sq ft |
As you can see, the input wattage is the main and only determining factor of how big a room can an efficient electric space heater heat up.
Be mindful of these wattage numbers whenever you see that a certain electric space heater uses ‘less electricity than comparable units’.
With all this in mind, let’s check which are the most energy-efficient electric space heaters currently on the market:
List Of 5 Most Efficient Space Heaters
- Most Energy Efficient Space Heater: Dr Infrared Heater DR968 (Auto Energy Savings Model)
- Most Efficient Oil Filled Heater: DeLonghi KH390715CB5 (Quietest Space Heater)
- Most Efficient Convection Panel Heater: DeLonghi SlimStyle (EcoEnergy Mode)
- Best Low Wattage Low Amp Space Heater: EconoHome Heater (Lowest Wattage)
- Efficient Infrared Space Heater: Costway Tower Heater (Tower Design)
Energy Efficient Heater: | #1 Dr Heater DR968 | #2 DeLonghi KH390715 | #3 DeLonghi SlimStyle | #4 EconoHome Heater | #5 Costway Tower |
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Heating Capacity: | 1,500 W / 5,000 BTU | 1,500 W / 5,000 BTU | 1,500 W / 5,000 BTU | 400 W / 1,400 BTU | 1,200 W / 4,100 BTU |
Supplemental Heating Area: | Up to 1,000 sq ft | Up to 1,000 sq ft | Up to 1,000 sq ft | Up to 270 sq ft | Up to 800 sq ft |
Efficiency Booster: | Auto Energy Savings | Thermostat + Quiet | EcoEnergy Mode | Low Wattage | Tower Design |
Max. Cost Per Hour: | $0.20 per hour | $0.20 per hour | $0.20 per hour | $0.05 per hour | $0.16 per hour |
Price: | $$$$ | $$$$ | $$$$ | $$$$ | $$$$ |
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Availability: | Check Price | Check Price | Check Price | Check Price | Check Price |
1. Most Energy Efficient Space Heater: Dr Infrared Heater DR968 (Auto Energy Savings Model)

Heating Capacity: | 1,500 W / 5,000 BTU |
Supplemental Heating Area: | Up to 1,000 sq ft |
Efficiency Booster: | ECO Auto Energy Savings |
Max. Cost Per Hour: | $0.20 per hour |
Dimensions (LxWxH): | 13 x 11 x 16 inches |
Weight: | 19 lbs |
Price: | $$$$ |
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As we have seen, the sheer number of available temperature modes an electric space heater can be set to be the main factor in increasing energy efficiency. Dr Infrared Heater DR968 doesn’t only have copper PCT and a wide 50°F to 85°F temperature range; it, even more importantly, has ECO auto energy savings mode. That makes the Dr Infrared Heater DR968 the most energy-efficient space heater that runs on electricity.
The Dr Infrared Heater DR968 has two main input wattage settings: 1,500W high setting and 1,000W low setting. Both settings are quite high; that’s why Dr Infrared Heater DR968 has a high heating output. In fact, when used as a supplemental heating unit, it can provide supplemental heat to up to 1,000 sq ft spaces.
The key to energy efficiency is the ECO auto energy savings program. This program automatically correlates the heating output of Dr Infrared Heater DR968 with the heating needs very effectively. In turn, this will help you to burn less electricity to adequately heat up the space you put the Dr Infrared Heater DR968 in.
When you run it at 100% heating output, it will cost you at most $0.20 per hour. This is calculated by knowing that a 1,500W heater requires 1.5 kWh per hour and using the national average price of electricity ($0.1319 per kWh).
All in all, Dr Infrared Heater DR968 is one of the best and most reliable space heaters in general. With ECO auto energy savings mode, it is also the most energy-efficient electric space heater currently on the market:
2. Most Efficient Oil Filled Heater: DeLonghi KH390715CB5 (Quietest Space Heater)

Heating Capacity: | 1,500 W / 5,000 BTU |
Supplemental Heating Area: | Up to 1,000 sq ft |
Efficiency Booster: | Thermostat + Quiet |
Max. Cost Per Hour: | $0.20 per hour |
Dimensions (LxWxH): | 5.9 x 13.8 x 24.8 inches |
Weight: | 26.1 lbs |
Price: | $$$$ |
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Oil-filled radiator heaters are both safe to use and cheap to buy. As far as the energy efficiency is concerned, they have an edge over standard electric heaters because the oil does hold some residual heat; metals less so. DeLonghi KH390715CB5 is one of the most popular and definitely the most energy-efficient oil-filled radiator heat.
First of all, DeLonghi KH390715CB5 has not 2 but 6 main heating settings, namely 600W (Low), 900W (Mid), and 1,500W (High); these are the main setting. That gives it extra flexibility when it needs to satisfy the heating needs exactly. Using exactly the right amount of electricity to adequately heat a room is the name of the game when the energy efficiency of electric space heaters is concerned.
On top of that, DeLonghi KH390715CB5 comes with an energy-saving thermostat. This is a specific heating output mode that is concerned with reducing electricity bills. It works by DeLonghi KH390715CB5 automatically adjusting the heating output (via the combination of 6 different heating settings) to match the heating needs and reduce the energy expenditure in the process.
This is also one of the few energy-efficient space heaters you can get for less than $100. It is, however, not built out of very solid metals (copper, iron, nickel) as most of the high-end classic space heaters.
Because it doesn’t use a forced air heating method, it is also running very quietly for a space heater and can be used in bedrooms.
All in all, the DeLonghi KH390715CB5 is the best price-performance space heating on the market. Its an energy-efficient oil-filled radiator heater that can provide supplemental heat to up to 1,000 sq ft at a minimum cost of the unit and minimum electricity costs:
3. Most Efficient Convection Panel Heater: De’Longhi SlimStyle (EcoEnergy Mode)

Heating Capacity: | 1,500 W / 5,000 BTU |
Supplemental Heating Area: | Up to 1,000 sq ft |
Efficiency Booster: | EcoEnergy Mode |
Max. Cost Per Hour: | $0.20 per hour |
Dimensions (LxWxH): | 26.9 x 3.5 x 18.1 inches |
Weight: | 18.3 lbs |
Price: | $$$$ |
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Convection panel heaters are becoming increasingly more popular. This is because they are pretty much the safest space heater to use indoors and are notoriously easy to install; just plug them into a 120V standard outlet, and press ‘On’.
By far the best and most energy-efficient convection panel heater is the De’Longhi SlimStyle. This is a superbly designed heater, and that doesn’t only mean the visual aspects (which are pretty sleek given the slim design).
This is one of the few 1,500W heaters with dual fans. Every heater needs a fan (powered by a motor) that distributed the heat evenly across the room. De’Longhi SlimStyle has 2 fans; that helps it to more evenly distribute the hot air, and do so faster than comparable units.
For energy efficiency, you have an EcoEnergy mode that ‘automatically saves energy’. That ‘automatically’ means that the heating output of this convection panel is precisely correlated to the heating needs. You don’t waste any more energy than you need to.
It’s also powerful enough (with 1,500W max. input) to heat up larger rooms (as a supplemental heating unit).
The cons of De’Longhi SlimStyle are few; most of them have to do with the elongated design. This convectional panel heater is about 27 inches long, does take some space, and can easily fall down if you hit it with force (or if your dog jumps into it or cat jumps on top of it).
In short, De’Longhi SlimStyle is one of the safest and most aesthetic space heaters. The EcoEnergy mode also makes it the most efficient convection panel heaters and De’Longhi is a well-known and reliable brand:
4. Best Low Amp Space Heater: EconoHome Heater (Lowest Wattage)

Heating Capacity: | 400 W / 1,400 BTU |
Supplemental Heating Area: | Up to 270 sq ft |
Efficiency Booster: | Low Wattage |
Max. Cost Per Hour: | $0.05 per hour |
Dimensions (LxWxH): | 29.3 x 3 x 26 inches |
Weight: | 17.8 lbs |
Price: | $$$$ |
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EconoHome wall-mount space heater is a space heater well-known for its energy efficiency. It’s one of the few space heaters that can be mounted on the wall and it does cost a max. $0.05 per hour to run. It costs less to run the EconoHome heater than it costs to run most other space heaters.
In fact, you might see that the EconoHome “Save up to 50% of heating costs”. As we have written in our short guide before the comparison table, you do need to be careful when looking at such statements.
EconoHome costs dollars to run and reduces the electricity bills because it’s max. electricity input is only 400W. Most space heaters are powered by 1,500W and require about 3 times more energy input and expenditure. However, they also generate 3 times more heating output. This is a low amp space heater that draws 3.3 amps when operating at 100% output. In short, you can put 3 or even 4 of these low amp space heaters on the same outlet (15A breaker).
EconoHome is a very fine heater for supplemental heating for smaller rooms. It will require a minimal amount of electricity to run, that’s true. But you can’t really get a lot of heat from a 400W; this is the main con of this small efficient electric space heater.
All in all, EconoHome can be mounted on the wall and does spend only 0.4 kWh to run per hour (at 100% heating output). The problem is that it generates way less heat than standard 1,500W space heaters:
5. Efficient Infrared Space Heater: Costway Tower Heater (Tower Design)

Heating Capacity: | 1,200 W / 4,100 BTU |
Supplemental Heating Area: | Up to 800 sq ft |
Efficiency Booster: | Tower Design |
Max. Cost Per Hour: | $0.16 per hour |
Dimensions (LxWxH): | 11 x 6.7 x 22.4 inches |
Weight: | 6.7 lbs |
Price: | $$$$ |
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Infrared space heaters are not generally considered very energy-efficient. That’s because electricity needs to be used to generate infrared radiation, and that’s not a 100% efficient process. However, if you consider that the generated heating output serves solemnly to heat a person (not the whole room), you can say that you get some kind of energy efficiency from these infrared space heaters.
Of course, some infrared heaters are more energy-efficient than others. Costway, for example, is probably the most energy-efficient infrared space heater, primarily due to its striking tower design.
Infrared heaters are used to heat a person. To improve energy efficiency, you need a heater that will direct as much of the infrared radiation (generated by the electricity we invest) onto the body of a person. The tower design is a good way to do that; the prolonged heater will radiate a higher percentage of its infrared warming radiation onto the body of a person and heat him or her.
However, we do need to keep in mind that using electricity to generate infrared radiation is not a 100% efficient process. Using electricity to create heat, for example, is a very efficient (nearly 100% efficient) process. That means that infrared space heaters are not as energy efficient as traditional electric space heaters.
If you do want an infrared heater that is as efficient as infrared heaters can be, you should look no further than the Costway infrared heater. With its tower design, you will get the most heat for your buck:
These were some considerations about picking the most energy-efficient space heaters, powered by electricity. It’s comparatively hard to use pure specifications to tell which space heater is more efficient than others; the key are the eco-friendly heating modes. Hope all of this helps a bit.
thanks alot of information
Great overview. Is there a recommendation for which of the space heaters can be plugged into a battery pack vs. a standard 110-120 wall outlet? I have a Yeti 3000X and need something to heat one room during power outages.
Hi Shirl, all of these space heaters can be run with a Yeti 3000X. The more energy efficient they are, the longer they will last; so the #1 Dr Heater DR968 is the obvious choice here. Hope this helps.