Here, we’ll look at several emergency sources of light and heat you can cheaply acquire, easily store, and effortlessly put together. Then, we’ll gauge their practicality, measure their efficiency, and dispel a few myths along the way. I’ll tell you which we think are the safest and which can turn your disaster into a more significant crisis. You won’t want to skip through this content, especially if you are going to rely upon one of the heating or lighting methods discussed in this video as your primary backup after a disaster. The truth about their risks and actual capabilities might surprise you.
When the lights and heat go out during the winter, you must understand how to create your own from things you may already have around the house or can be cheaply acquired, easily stored, and effortlessly put together after a disaster. These first two can provide light but won’t give you much heat beyond keeping your fingers warm. To read about any of the sources of light covered here, visit cityprepping.com/heaters.
OIL LAMPS
An oil-based lamp is easy to make. Oil lamps, the oldest form of candles, have been used since the 2nd century BC, evolving from clay and stone to bronze and glass until the advent of electricity in the late 19th century. Various oils like whale, olive, coconut, and fish oil were used, each with different flammability levels. While a single oil lamp provides only a small flame, it can keep fingers warm, heat liquid, or be combined with others for more warmth. Its primary purpose is just to have a long burning source of light to see by.
To make an oil lamp, you need a container, a wick, and the oil. That’s it. Here, I use a single-serving stainless steel teapot, a single strand of a cotton mop, and some grape seed oil. Simply dip the wick in oil, insert it into the spout of the teapot, then fill the teapot halfway with oil. Once the wick is lit, it will keep burning but can easily be extinguished. I found that this design would stay lit with a very small flame for about 10 minutes without wick adjustments. The flame was too small to see by. Missing from my design was a wick holder or what’s called a wick trimmer. This is a bead that the wick is threaded through at the top to keep it from falling into the oil or burning too rapidly, as it does here.
A modern take on the oil lamp can be accomplished with simply a can of Crisco or a jar of tallow and the same cotton strand of a mop. Any rendered fat will work with this method. Here, I put it into the can of Crisco vegetable shortening and moistened the top of the wick with the oil. It lights easily and stays lit for hours and hours. I went about my business and came back to it later, and it was still lit. As a light source, it is sufficient. As a heat source, it’s useless.
FLOWER POT HEATER
To test these heat sources, we will use the upside-down flower pot heater you may have seen popularized online. These do and don’t work, as I will explain here. It’s a simple design. You only need a terra cotta flower pot and two bricks to elevate it. I can use a few pennies stacked on top to warm a cup of water. I also use a ceramic tile under this as an added layer of protection and safety.
In theory, the heat source, when placed underneath, warms the air inside the pot. It pulls in cold air from the bottom and funnels hot air out the small hole on the top. A combination of radiant heat and convection air heats the area immediately around the flower pot. The terra cot clay absorbs some of the heat and radiates it gently into the environment. To test these various methods for heating, we’ll measure temperatures along the way with an infrared thermometer and a kitchen thermometer.
TEA CANDLE HEATER
You typically see these flower pot heaters combined with tea candles clustered together. Tea candles are also great for emergencies, but we think they are better for light than as a heat source, so if you are relying upon them for heat, you may be disappointed.
First, a candle only puts out 75-85 BTUs (British Thermal Units, the units by which we measure heat). To raise the temperature of a 10×10-foot room with an 8-foot ceiling by 1°F, you would need at least one candle burning for 11 hours, assuming perfect conditions with no heat loss and even distribution. That said, you need proper ventilation, so a window cracked even ¼ of an inch or a slight draft would easily negate the candle’s heating power.
So they are often coupled for this flower pot heater, as I do here. That cranks up the heat, and yes, I do gain some radiant heat increases from this. The problem is I have eight open flames burning in close proximity to each other, and most people don’t try to contain them as I do here with this aluminum tray. The second problem is that all of that concentrated heat completely liquifies the tea candle wax, resulting in it burning faster. It can also lead to the wax igniting. When multiple tea candles are grouped in a confined space like a flower pot heater, the increased heat can raise the temperature of the wax, potentially leading to it reaching its flash point and igniting. While it’s not guaranteed to happen, it’s a safety concern worth being cautious about. This is also a good spot to mention that you should have a fire extinguisher or fire blanket handy any time you are working with open flames.
Tea candles are good for light and comfort, and they provide enough heat to keep fingers warmer. While you can use several tea candles in your flower pot heater, understand that the temperature gains are marginal and the safety concerns are higher. You will get some radiant heat, but it will be confined to the flower pot itself. A more efficient method is Chafing fuel cans.
CHAFING FUEL CANS
If you’ve ever worked in catering or food services, you’re likely familiar with chafing fuel cans. These cans can get extremely hot, as they’re designed to keep food warm. From an emergency fuel source perspective, they’re ideal. They have a long shelf life. They are completely self-contained and portable, making them ideal for bug-out bags or camping.
Depending upon the type and size, Chafing fuel cans will generate between 890 and 1630 BTUs per hour. Compare that to the candle’s paltry 75-85 BTUs. In the same ten-by-ten room with an 8-foot ceiling, it would take about an hour to raise the temperature one degree in perfect conditions. That’s still not enough to make an area livable, but it might make a small area bearable and keep it from getting deadly cold.
The fuel inside is either liquid or a semi-solid gel, and the cans seal tightly to prevent spillage or evaporation. They burn for between 4 and 6 hours. This fuel can I picked up for around $10 and has an attachment on top for cooking, so I wanted to see how hot it actually would get. After 20 minutes, it managed to raise the temperature of 8 ounces of water to around 175 degrees. That’s far short of boiling and uses too much of your fuel source to be called efficient. It’s perfect for tea or hot beverages to keep you warm. The same type of chafing fuel can under the flower pot only raised the water temperature to 125, this is because the cup is much further from the heat source. So, you can’t solely rely on this for all your heating and cooking needs. That is hot enough to pasteurize water to make it safe from biological contaminants to drink. It’s hot enough to cook an egg over. This isn’t a long-term solution, but we are looking for efficiencies in a post-disaster environment, and this works for that.
I added a second chafing can under the pot, and with some slight reconfigurations, I could probably fit three under there. Unlike the basic tea candles, I don’t risk the wax spontaneously igniting with these. Two or three of these under our flower pot heater are going to create a relatively safe radiant heat source on par with a small radiator. It offers localized warmth and is ideal for small, well-ventilated spaces. One chafing fuel can under our flower pot heater produced a gentle, radiant heat source. With two cans, a cup of water was heated to 148°F in 5 minutes, sufficient for pasteurization but not boiling. It probably would never boil because of the distance from the actual flame to the cup of water. It also was an effective radiant heat source. The pot reached temperatures above 300 to 400 degrees°F, creating gentle, localized radiant heat. It would not be efficient to raise the temperature in a room larger than 10 feet by 10 feet. However, if you had this within a tent environment, you could create a warm microclimate for yourself in just a few minutes.
I also have to acknowledge the safety factor of these. They have a very hot flame that is easily extinguished just by putting a lid on top. If this is all you have to keep warm with, it’s more reliable than a fire, portable, and could prevent you from getting frostbite or your core temperature dropping too much, especially if you couple it with layers, hot water bottles, or a smaller microclimate area. I recommend having a few of these in your winter prepping supplies and maybe even one or two in your bug-out bag.
PAINT CAN HEATER
By far, the most dangerously large hot flame is generated by this paint or coffee can heater, which you may have seen in other places on the internet. You know we had to test it out. To make it is a simple process. You only need an all-metal, unlined paint or coffee can, 70% isopropyl alcohol available at most stores, and a roll of toilet paper. Use an all-metal can like an unlined paint can or coffee can. Here, I use a coffee can. I remove the label so it doesn’t melt or burn. Jam a roll of toilet paper into it by scrunching it down and working it into the can. Remove the cardboard inner roll, and jam more toilet paper into the center.
Once it is all tightly packed in there, pour in 70% isopropyl rubbing alcohol. You want to continue to add until the toilet paper is completely saturated, but not to the point where alcohol sits on top of the paper. The toilet paper serves two functions with this heating unit. First, it wicks the alcohol up to the combusting surface. That’s not its main function, however, because this alcohol is very flammable on its own. Its main function is to protect you from accidental spills. If this is knocked over, the toilet paper prevents flaming alcohol from spilling out.
I fitted this with the cooking top from the emergency chafing fuel can cooker and was able to get water to boil in just eight minutes. This burns very hot and for a long period of time. It cranks out a lot of heat, too. It is a bit of an unruly flame, and it doesn’t burn 100% clean, though I don’t think toxic fumes are as much of a concern with alcohol of this nature. Technically, it’s considered clean burning. The large flame is more of a safety concern. Fortunately, with this design, it is easy to extinguish simply by placing a flat object over the top.
As for the heating capabilities of this, sixteen ounces of 70% Isopropyl Alcohol will generate 13,000 BTUs. A coffee can heater burning isopropyl alcohol with a 6-inch diameter can produce around 812.5 BTUs per hour. Raising the temperature of a 10x10x8 room by 1°F would take just a couple of minutes, assuming perfect conditions with no heat loss. Sixteen ounces of isopropyl alcohol will take between 4-6 hours to burn off. Don’t try to put all 16 ounces in a container that won’t accommodate it easily. Remember, you only want to fill the toilet paper to the saturation point and not where you can see liquid pooling on top. Second, never refill a container while it is lit or immediately after extinguishing it.
This improvised heater is highly efficient, providing substantial heat for its simplicity and low cost. However, its exposed, extremely hot flame presents significant safety risks. While the base of the can may remain cool to the touch, moving it while lit is extremely dangerous and should be avoided. This type of open flame can quickly turn a difficult situation into a disaster if not handled carefully, so use it with caution and never leave it unattended. Fortunately, the materials needed for this heater are compact and may already be part of your emergency supplies. Many preppers find it a useful, temporary heat source—but always prioritize safety to prevent accidents.
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A disaster can easily be made magnitudes worse when you introduce open flames to it. In the aftermath of a disaster, though, you’ll need both light and heat. If you need the kind of heat that will keep you from freezing to death, then consider the emergency alcohol can heater. If you want a combination of light and heat, consider the chafing fuel cans. It’s our opinion that the chafing cans are the safest and the tea candles probably even more dangerous than the high heat generating alcohol burner. If you only need a little light, tea candles or even a basic oil lamp might be your easiest solution. Whichever you choose, use an abundance of caution and couple your method with our other Winter Survival Tips videos I’ll link to below. The first is 9 Survival Tips For A Winter Power Outage, and the second is 30 Affordable Winter Survival Items to Get Now. Coupling the heat and light solutions discussed here with the solutions and items discussed in those two videos to watch next will ensure you have what you need when the lights are out, and the temperature is dropping so you can see and keep warm.
As always, stay safe out there.
LINKS:
9 Survival Tips For A Winter Power Outage – https://youtu.be/vAHyJrmzINs?si=IYfQE6OM83Yxbroh30 Affordable Winter Survival Items to Get Now – https://youtu.be/OzEyrahA8Q0?si=GoCIQ0ver4sSLCYY