20 Alternative Heat Sources for Power Outages

When the power goes out in the winter, furnaces, baseboard heating, and electric space heaters are no longer an option. For most, the only way to stay warm is by using an alternative heat source. But many common options are not optimal, or even remotely safe, for indoor use.

In this article, we look at 20 alternative heat sources for power outages. Many of these must be planned for or purchased ahead of time. But others can be thrown together in the moment if a power failure catches you off guard.

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Alternative Heat Sources To Use in a Power Outage

Non-electric heat sources come in two main categories: those that run on alternative power or fuel and those that use existing heat sources or non-fueled heat to increase the warmth of a space.

We recommend having one or more of both types on hand for possible emergencies. These, along with extra food and water, can be the difference between life and disaster in a long-term power outage.

1. Wood Burning Stove

wood burning stove and firewood

One of the most effective methods for heating a home without electricity is the same one our ancestors used for hundreds of years. Wood-burning stoves require only wood to produce heat and can be used to warm large spaces with minimal work.

Many older homes feature wood-burning fireplaces. While these work in much the same way as a wood-burning stove, they do not give off as much heat. Most of the warmth they create is lost to the outside, either through the wall or the chimney.

Wood-burning stoves, on the other hand, sit away from the wall, allowing heat to radiate from all sides. If power outages are a likely problem and your climate is known to get cold, it is worth replacing your traditional fireplace with a wood-burning stove. But either will work in an emergency to provide heat.

Considerations for using a wood-burning stove in an emergency:

  • Must have a large supply of wood to keep it running
  • Occasional maintenance and cleaning are needed to assure safe operation
  • Must be in place before the power outage occurs to be useful

2. Masonry Heater

Masonry heater
Waroomniet, CC BY-SA 3.0, via Wikimedia Commons

A masonry heater looks similar to a traditional wood-burning fireplace, but with a few key differences that make it far more effective for providing warmth.

Like a regular fireplace or wood-burning stove, a masonry heater features an opening where the fuel, usually wood, is burned. But unlike these more familiar wood burners, a masonry fireplace is surrounded by materials with a high thermal mass. Typically, they are made with large stones, tile, concrete, or brick.

These heat-retaining materials surround the fireplace on all sides and run along the chimney vent to the ceiling. Much of the heat produced by the fire is captured in this casing and slowly dissipated to the surrounding room.

Masonry heaters are much slower to warm a space than wood stoves, but they produce heat for much longer, even if the fire goes out. Most importantly, far less heat is lost to the outside using this setup. These factors make this heating option highly effective at preserving fuel during an emergent situation.

Considerations for using a masonry heater in an emergency:

  • Requires a large supply of wood
  • Occasional maintenance and cleaning are needed to assure safe operation
  • Must be in place before the power outage occurs to be useful
  • Different types of masonry heaters can run on different kinds of fuel, including natural gas and pellets

3. Pellet Stove Heating

Modern domestic pellet stove

Pellet stoves function by burning compressed wood or biomass pellets at high temperatures to create heat. Because the fuel is highly compressed, it burns at a higher temperature and for longer periods than wood logs.

Most modern pellet stoves feature a hopper that automatically feeds pellets into the burner for continuous heat with little need for tending. But keep in mind, many of these features require electricity to work. If you plan to use a pellet stove for emergency heat, be sure the feeder can be operated manually and there is a way to light the pellets outside of an electric ignition.

One big advantage of pellet stoves as an emergency heat source is that the compressed pellets require less room to store than wood.

Considerations for using a pellet stove in an emergency:

  • Must have pellets on hand
  • Occasional maintenance and cleaning are needed to assure safe operation
  • Some pellet stoves require electricity to operate (battery backup is available)

4. Catalytic Gas Heater

Catalytic gas heaters are specialized heating appliances typically used in industry. They create heat by combining fuel (usually propane or natural gas), a preheated catalyst (usually a platinum-coated plate), and oxygen. These three materials come together to produce a chemical reaction that gives off heat. You can learn more about how these function here.

This type of heating is used most often in situations where an open flame would create a hazard.

Catalytic heaters are highly efficient, which means even a small unit is powerful enough to heat large spaces. And because they do not have an open flame, they are safe to use indoors in most situations. You can find catalytic gas heaters in portable or mounted options.

Considerations for using a catalytic gas heater in an emergency:

  • Are harder to find, so be sure to purchase ahead of time
  • Must have the right fuel on hand
  • Can get very hot to the touch, so caution should be used around children and pets

5. Rocket Mass Heater

cob style rocket mass heater
Derrick Parker, CC0, via Wikimedia Commons

A rocket mass heater, or rocket stove mass heater, works similarly to a masonry heater but with additions that make them highly fuel efficient. There are many ways to build a rocket mass heater, but all consist of an insulated combustion chamber and an extended exhaust vent that is surrounded by high thermal mass material.

Combustion inside a rocket mass heater is nearly complete, which means they require 90% less fuel material than traditional wood-burning stoves. In an emergency, this can make a huge difference. Additionally, the thermal mass surrounding the venting claims enough heat to stay warm for days following use.

These innovative heating systems can be built into the home or created as large portable units. You can purchase premade rocket heaters or build your own. They require wood for burning, but you’ll need much less of it on hand compared to a traditional fireplace.

Considerations for using a rocket mass heater in an emergency:

  • Must be in place or on hand before the emergency
  • Require wood for fuel

6. Gas Fireplace

In many homes, gas fireplaces have replaced traditional wood-burning fireplaces. While these don’t put out nearly as much heat as wood burners (especially when the electric blower is off) they can be used for heat in an emergency.

Gas fireplaces run off propane or natural gas. Most feature electrical components, such as an electric ignitor, digital control panel, and blower. But many options are built with battery backups or manual overrides that allow you to use them even when the power is out.

One of the benefits of using a gas fireplace for emergency heat is that these units are typically tapped into the home’s gas system. This means you do not need to store emergency fuel in most cases.

Considerations for using a gas heater in an emergency:

  • Must be installed before an emergency
  • The unit must have a battery backup or manual overrides

7. Solar Air Heater

Solar air heaters work in much the same way as solar water heating systems. This ingenious technology cycles air from your home (or outside) through a large black solar sheet attached to your roof or outer wall. As the sun heats the solar sheet, the cycling air warms before being pushed back into the house.

To be effective in an emergency, the fans in your solar air system need to run off solar energy. You can find systems like this on Amazon or build them yourself.

While these systems are not likely to create enough heat to warm your whole house, they can be very helpful during power outages. These systems should be placed in the room or rooms you plan to spend the most time in during these kinds of emergencies.

Considerations for using a solar air heater in an emergency:

  • Useful for heating small spaces
  • Requires sunlight to operate
  • Best for south-facing properties with plenty of sunshine

8. Generate Your Own Electricity

portable generator

One of the most useful items to have in a power outage is a generator. These machines create electricity by using fuel to create an electrical current. Residential and portable types typically run on gasoline, but you can also find diesel, propane, and natural gas-powered generators.

Generators allow you to plug standard home devices into them. In order to use a generator to create heat, you’d also need to have an electric heater on hand.

Because they run on combustion, generators should never be used inside the home. In fact, it is recommended they be placed a minimum of 20 feet away from structures. You’ll need an extension cord to feed the electricity into the home to run your electric heater.

Considerations for using a generator in an emergency:

  • Must have plenty of fuel on hand
  • Requires a compatible electric heater
  • Must be used according to guidelines to assure safe use

Portable generators are available on Amazon.

9. Kerosene Space Heaters

Kerosene heater

Kerosene space heaters are an option for emergency heating, though they are not the first one that should be considered.

These portable heaters work by burning kerosene to create heat. Indoor-safe units are ventless, which prevents many of the toxic fumes associated with burning this kind of fuel from being released. However, when burned in low-oxygen environments, they can put out deadly carbon monoxide.

While kerosene is more expensive than propane and harder to find, it does have the benefit of being safe to store indoors. For those with limited emergency storage space, this might be one reason to consider a kerosene space heater over the alternatives.

Considerations for using a kerosene heater in an emergency:

  • Easy to store for emergency use
  • Requires kerosene fuel to be kept on hand
  • Even indoor safe models come with major safety risks

10. Propane Heaters

indoor safe propane heater

Propane heaters are very similar to kerosene heaters but come with a few advantages.

For one, propane fuel is typically inexpensive and easy to get. It is also safer to use in an indoor environment so long as the model is rated for that use. These units come with low-oxygen shut-off features and are much less likely to put off toxins compared to kerosene.

You can learn more about the differences between propane and kerosene heaters in our comparison guide.

Like other fueled space heater options, you’ll need to have plenty of fuel on hand to use a propane space heater in an emergency.

Considerations for using a propane heater in an emergency:

  • Easy to store for emergency use
  • Requires propane fuel to be kept on hand
  • Propane must be stored outdoors

11. Ethanol Fireplaces

modern ethanol fireplace

Ethanol fireplaces, also known as bio fireplaces, create real flames by burning ethanol. This clean burning fuel releases no fumes or smoke and does not require ventilation.

Typically, bio fireplaces are used as a visual design feature inside the home. While they do create some heat, it is far less than what you get from a gas or wood-burning fireplace. But, in an emergency, they can be used to warm the surroundings or help keep an enclosed room more comfortable.

One benefit of these kinds of fireplaces is that some models are portable. This means you can place them on counters or tables and move them as needed. But, because they use an open flame, caution should always be used around these units.

Considerations for using an ethanol fireplace in an emergency:

  • Requires a large supply of fuel (1 quart of ethanol burns for up to 5 hours)
  • The open flame can be a safety hazard
  • Do not put out a ton of heat

12. Alcohol Gel Fireplaces

Alcohol gel fireplaces are very similar to ethanol fireplaces with a few key differences.

These fireplaces burn alcohol gel to create real flames. Like ethanol, this product burns cleanly without releasing toxins or smoke. Therefore, no ventilation is needed.

But, instead of relying on a fuel tray that must be constantly refilled, these utilize pre-filled canisters for operation. These canisters do not last as long as an ethanol reservoir and the flames created put out even less heat.

Like bio fireplaces, these are typically used as a design element. But in an emergency, they can be useful for generating some heat. The portability of some models makes them easy to use, just be mindful of the open flame.

Considerations for using an alcohol gel fireplace in an emergency:

  • Requires a large supply of fuel (1 canister burns for up to 3 hours)
  • The open flame can be a safety hazard
  • Do not put out a ton of heat

13. Canned Heat

canned heat

Canned heat, also known as Sternos, chafing dish warmers, and cooking fuel wicks, are self-contained containers of ethanol or alcohol gel that are lit like candles. They are most often used to heat large pans of food at buffets. But they make great emergency heat creators to have on hand.

A single canister of canned heat won’t put out much warmth by itself. But, you can combine these with thermal mass materials or specialty stoves to increase their heating potential. The Vesta Self-Powered Heater is a great example of the latter.

Canned heat canisters don’t release toxins or smoke and are easy to store. This makes them a great option for those preparing for the possibility of a short-lived winter power outage.

Considerations for using canned heat in an emergency:

  • Need to keep plenty on hand (one canister lasts 2 to 6 hours)
  • Easy to store
  • Puts out the most heat when used in conjunction with thermal mass material

14. Candles and Terracotta Pots

DIY terracotta pot heater

One simple way to create heat during a power outage using household items is with a candle and terracotta pot.

Like bricks, stone, and tile, terracotta has a high thermal mass. This means it absorbs heat and slowly releases it with time. By placing an inverted terracotta pot above a lit candle, you can capture the heat from the flame to warm the air.

These homemade heaters get very hot, so watch them carefully. And make sure the surface under the candles is heat resistant.

To create this homemade heating system:

  1. Prop up an upside-down pot using bricks, ceramic coasters, trivets, or other heat-resistant material. 
  2. Cover the hole in the pot using tin foil or another heat-resistant item. 
  3. Place a lit candle under the pot.

Considerations for using a propane heater in an emergency:

  • Can use tea lights or regular candles
  • Terracotta works well, but any heat-resistant basin with thermal mass can be used

15. Soapstone Blocks

Soapstone has a very high thermal mass. This makes soapstone blocks valuable for retaining heat when heat is hard to come by.

During power outages, these blocks can be placed near working heat sources like wood burners, to collect heat. Once the fire is out, they will continue to expel heat for hours. Alternatively, they can be heated and then moved into other areas to extend the heating radius.

Soapstone blocks are also great for collecting solar heat. By placing them in a sunny window or outside on a sunny day, you can collect heat to keep your space warmer at night.

Considerations for using soapstone blocks in an emergency:

  • These are items you’ll want to have on hand in your emergency storage
  • Soapstone requires an external heat source (sun, fire, infrared propane heater) to collect heat from
  • Warmed soapstone is best used in small, insulated spaces

16. Water Barrels

Like soapstone, water has a high thermal mass. Large jugs or barrels of water can be used to capture heat from emergency heat sources or from the sun.

Because of the difficulty associated with moving large barrels of water around, one of the best ways to use them is to set them up near the windows in a south-facing room. The barrels will collect heat all day, then slowly release it into the room overnight.

Alternatively, you can set the water up near your heat source to capture and slowly release heat into the room. Just be sure the plastic doesn’t get so hot that it melts.

Considerations for using water barrels in an emergency:

  • Requires having large barrels on hand
  • Consuming water after heating it in plastic barrels is not recommended

17. Mylar Thermal Blankets

mylar blanket

Thermal blankets may seem a little simple, but they can make a big difference during long-term outages. These “space blankets” work by reflecting your body’s heat, allowing you to warm yourself.

Mylar blankets are easy to keep on hand for emergencies and can be especially helpful overnight. By using these blankets when you are stationary, you can conserve your other emergency heating methods so you don’t run out of fuel.

Considerations for using mylar thermal blankets in an emergency:

  • Compact, affordable, and easy to store
  • Can also be used over windows at night to prevent heat loss

18. Indoor Tent

It may seem thin and flimsy, but tent material is designed to capture heat. That’s why tents are so good at keeping us warm even when camping in the thin mountain air.

Staking up your tent inside during a power outage gives you an extra layer of insulation against the cold. They make an especially good place for the family to sleep. The not-so-breathable material easily captures body heat.

While many heat sources are not safe for use inside a tent due to the risk of fire, there are some things you can do to warm your tent, including:

  • Place warmed water or soapstone inside
  • Put your generator-run electric heater inside
  • Vent your solar air heater into the tent
  • Use thermal blankets and sleeping bags

Considerations for using a tent in an emergency:

  • Compact options are easy to store
  • Zip up all vents and put on the rain fly to trap as much warm air as possible
  • Open the door flap to the tent as little as possible
  • Small, short tents work best for emergency warmth

19. Hand Warmers

If the weather outside is especially cold, you may be tempted to overuse your emergency heat source in order to stay comfortable. Unless you’re certain of when the power outage will end, this is never a good idea.

One way to make yourself feel warmer so you can rely less on fueled heat sources is to use hand warmers.

Hand warmers in gloves, shoes, pockets, and on the back of the neck, can go a long way to making you feel warmer. These are especially helpful during the day when staying close to your best heat source is not possible.

20. Body Heat

When a power outage and cold weather have your house feeling frosty, it is best to have everyone stay together in the same room. Not only does this conserve your heating fuels by allowing you to use fewer heaters at once, but it also adds heat through body heat.

The smaller and better insulated the room you choose to gather in, the more you’ll notice the warming effect bodies can have on the air.

Beware of The Dangers of Emergency Heat Sources 

Almost all fuel-based heat sources come with some risk when used indoors. To keep yourself and your family safe, be sure to follow these general guidelines:

  • Only use heaters inside that are specifically advertised for indoor use.
  • Read all product instructions carefully and follow them precisely, especially in terms of venting and airflow.
  • If you have small children or pets, use gates, cages, or similar items to enclose the heater so no one gets burned.
  • Make sure heaters with an open flame are placed away from fabrics, furniture, and walls.
  • Be sure you have a working, battery-operated CO and fire detector in the same room as your heater.
  • Have your fire extinguisher on hand at all times.
  • When possible, opt for products that have safety features like tip-over switches and oxygen sensors.
  • Clean and maintain your emergency heating devices throughout the year, even when they are not being used.
  • Most emergency fuels have a shelf life, so be sure to check them periodically and refresh as needed.
  • Some heating products must be supervised during use and are not safe for overnight use; check your user guide for more information.

While it is possible to succumb to the cold during an emergency power outage, it is just as likely to suffer a disaster from improperly used emergency heating. Following these guidelines and staying vigilant can help avoid any problems.

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Author
Aaron Green
Aaron is the founder of and Essential Home and Garden. He likes to spend his spare time with his family, and doing DIY projects in the home and garden.

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