16.4 oz. propane tanks are a common energy source for camping stoves and small portable propane heaters. Although they’re lightweight, convenient, and easy to use, these propane canisters frequently frustrate campers and hikers who can’t keep track of how much propane is left.
You can check how much propane is left in your tank in a couple of different ways. It’s essential to measure your current tank with one you know is full, though. If you want to keep track of your propane and avoid running out when you’re in the backcountry, understanding how long the tank lasts.
Read on to find out how much propane a 16.4 oz. tank holds, how long it lasts under certain conditions, and how you can make an educated guess about the amount left in your current tank!
1-pound vs 16.4 oz. propane tank
In case there’s any confusion: propane cylinders aren’t typically rated by the ounce, but rather by pounds. A 16.4 oz propane canister is more commonly referred to as a 1-pound propane tank. That ounce number is the net weight of the contents, so the propane inside the tank weighs about 16.4 ounces.
1-pound propane tanks are used to power camp stoves for grilling, frying, boiling, and pretty much anything else you could do on a conventional stovetop. You can also power portable heaters and propane lanterns with them.
How much propane is in a 1-pound propane tank?
Alright, so there’s 16.4 ounces of propane by weight inside one of these tanks, but how much is that? Thankfully, science is here to help us figure it out. Don’t worry, we won’t get into the complicated stuff.
The first thing you have to understand is a unit of measurement called BTUs, which stands for British Thermal Units. One BTU is the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. If that sounds familiar, it’s because this is the U.S. equivalent of the metric calorie, which is the amount of heat required to heat one gram of water by one degree Celsius. Although it’s kind of a historical relic as far as measurements go, the BTU is still used to measure the sale of natural gas in the USA.
Propane has a BTU per gallon of 91,500. One gallon weighs about 4.23 pounds, so if we divide these two numbers we should be able to find out the BTU of a one-pound propane tank.
- 91,500 / 4.23 = 21,631 BTU per 1-lb propane tank
Fantastic, you might be saying. But how does that BTU amount translate into burn time for a portable camping stove?
How long does 1 BTU of propane last?
Since the larger one-gallon tank has more BTUs and therefore more propane, it’s not rocket science to deduce that it lasts longer than the smaller tank. So what is the connection between BTUs and burn time?
Let’s try to find the most convenient way to connect the two. You can’t very well count backward from 21,631 to keep track of how much propane you have. What throws most people off is that the size of the grill greatly impacts how long the propane bottle will last.
Thankfully, camp stoves don’t burn propane gas as fast as a large grill. A medium gas grill can burn through a 20-pound propane tank in as little as 10 hours, but it usually lasts 18 – 20 hours. A 20-pound tank has 4.73 gallons of propane. From this information, we can try to calculate a rough estimate of a per-BTU burn rate:
- 91,500 * 4.73 = 432,795 BTUs per 20-pound propane tank
You can also take a shortcut: multiply the BTU of a 1-pound tank by 20 and you’re not far off. If you’re using a medium gas grill and it lasts 18 hours, you can divide 432,795 by 18 to discover that roughly 24,000 BTUs are burnt per hour.
Burn rate for different propane accessories
If you’re using a backpacking stove rather than a full-on propane grill, that tank won’t have the same burn rate. The medium grill might have a burn rate of 24,000 BTUs per hour, but the smaller portable tank doesn’t.
Even a larger camping stove will have a higher burn rate than a single-eye backpacking model. Understanding how long that tank will last depends on how you’re using it. Of course, we don’t need to figure out the burn rate of a specific stove down to the decimal point.
Burn rate for backpacking stoves
If we were to assume that a backpacking stove was as powerful, the 21,631 BTUs would last about 90% of one hour or 54 minutes. Generally speaking, though, your grill would have to be working pretty hard to burn the whole canister at that speed.
Your grill should have its own burn rate in the information that came with it. You can use that burn rate to find out how long the tank will last according to the manufacturer.
Campers who really want to understand their own equipment sometimes measure how long it takes to boil a fixed amount of water, say one liter. You can use this information to calculate how much fuel you’ll need once you know the burn rate.
Since these tanks aren’t that expensive, you can measure how long it takes to boil water and keep it cooking for the ten or 15 minutes needed to fully cook your meals, measure how many meals you get in before you run out, and then you’ll have a rough per-meal burn rate. You can also measure how long each meal takes to make if you want a more illustrative number.
How long do most 1-pound propane tanks last?
From our experience, you can expect these little tanks to keep working for between 1 and 2 hours of total burn time. The more you use high heat, the more propane you’ll burn and the less time it will survive before needing to be refilled.
Most backpacking stoves and small campsite cooking equipment will last right in the middle, around 1.5 hours, operating on a mid-high heat for boiling water and slightly reduced to cook it for 10 – 15 minutes. As a concrete example, this is right on the money for a Coleman propane tank used at medium heat for reasonable lengths of time.
Bear in mind that you don’t have to spend an hour on your camping meals. The tank isn’t going to go out after a single day on the trail. In most cases, freeze-dried meals and prepped meals that only need heating can be prepared in as little as 5 or 10 minutes, so you should be able to get at least 8 and as many as 18 meals out of one tank.
How can I make my propane last longer?
Reduce the amount of time your propane torch, grill, or heater is on a high or medium setting and you’ll be able to stretch out the life of the tank. Here are a few more tips to make your propane cylinder last:
- Use Fire When Possible: Depending on where you’re camping, it might be easy to bring a firestarter and build a small campfire for boiling water and staying warm. The propane tank can be used as a backup or for stops during the day when you’re on the move or can’t otherwise make a fire.
- Eat Freeze-Dried Meals: These meals take a very small amount of water. All you have to do is boil the water, add the contents of the packet, let it heat up for a few minutes, and you’re ready to chow down. If you don’t have the cash for tons of these meals, cheaper dehydrated veggies and other foods work the same way as these entire meals. Bring some packets of BBQ sauce if you’re worried about bland food.
- Go Easy On Hot Drinks: Everybody loves a hot cup of coffee on a cold morning, but if you can’t build a small fire to boil water for your coffee or carry a dedicated coffee machine, it would be best to try and avoid too many cups. Rather than skipping cups altogether, you can try other methods like leaving your water in the sun to warm up so the propane has less work to do. Instant cold brew and iced coffee that can be made with cold water is another option.
- Weather Conditions Have An Effect: Wind can blow the heat away from your stove. Low temperature lowers the volume of propane, and frigid temperatures might affect how well your propane fuel cylinder continues to work. Water boils faster at higher temperatures but food takes more time to absorb water.
- Boil Water at 85% Capacity: The full power output of a propane stove will cause lots of heat to escape the cylinder at once. Most of that is probably just going to dissipate without having any measurable effect. When you’re boiling water or trying to heat something quickly, set the dial about 15% lower than the full setting to get it working quickly without wasting too much fuel.
Does propane go bad?
Great news if you’re worried about using your propane before it disappears: propane doesn’t expire. If your tank has been sitting somewhere dry and relatively warm through the winter, it should be alright to use it whenever you want. In fact, the propane can probably last much longer than that. Steel tanks can rust through and allow propane to leak out through the side. If a tank shows rust, don’t use it. It could also be empty due to a leak, but testing it could be dangerous if the tank isn’t completely empty.
The most important thing you can do to keep your propane audible even if it’s going to be sitting around for a little while is to make sure you use any protective cap that came with the model when it isn’t in use. Ideally, these tanks should be stored outdoors and completely away from any water that could cause rust.
Can you refill propane tanks?
Some Coleman propane fuel cylinders and similar models from competing brands come in refillable models with a special adapter that allows them to take more propane. Even if you have a refillable tank, return it to a professional who can top it off for you.
There are many tips and tricks on the internet for refilling a disposable propane tank. Something about the small size of these tanks makes people think it’ll be alright to doctor them.
In some cases, that might be the case. But it’s a huge risk that’ll only save you a few bucks in the end. Plus, even if you do get the tank refilled without blowing yourself up, the law in many places makes it illegal to transport that tank on any public roadway. You’re better off with a brand new tank.
What should I do with old propane tanks?
Once the propane is out, these canisters are considered household hazardous waste and must be taken to an approved disposal center near you. A quick google search can tell you where that might be based on your location.
Don’t ever throw these things in the trash or leave them outside anywhere. They’re still pressurized and present a danger to people. Plus, it’s a pretty large piece of trash to just leave lying around.
How to measure how much propane is left
If you don’t know how much is left inside the canister and you really don’t want to burn the rest off, you can use one of the following tricks:
- Weigh Your Propane Tank & An Empty One: The difference should be the weight of the remaining propane. Weigh the tank when you first get it so you can see what percentage of the full weight you have. If you don’t have an empty tank, the ‘tare weight,’ which is the weight of the tank itself, should be written on the tank or in the information pamphlet. The difference between the tare weight and what you see on the scale should be the weight of the remaining propane.
- Place the Tank in Water: When a full tank is in water, it sinks lower down but it still floats. You can place your tank in water and watch how it floats to gauge how much propane is left. As the water line is lower on the tank (or the tank is higher in the water, however you want to look at it) you can see your propane supply decreasing. It might not give you a precise number, but it should give you a relative indication.
Safety tips for camping with propane tanks
The main safety tips we’ve already discussed is to never, ever try to refill a disposable propane tank and don’t throw them away in the trash can.
When you’re cooking with a small propane cooking stove, watch your sleeves, feet, sleeping bag, or anything else that might get burnt. The wind is another huge consideration. It’s probably not wise to leave a propane tank burning inside your tent unless it has the necessary safety features to do that without burning the whole place down.
If you’re in a tent with low ventilation, you might want to use the propane tank to heat up hand warmers or just take the edge off before your body heat can warm up the inside of your sleeping bag. Carbon monoxide is a byproduct of propane tanks and without the right escape route, those fumes can have some terrible effects.
Propane is a great power source for cooking, heating, or lighting your way through the backcountry. Many campers can only rely on guesswork to plan on when their propane tanks will run out, though.
A one-pound propane tank should last for 1.5 hours of burn time. How you use the tank and the environmental conditions will affect how long this time truly is. It might be 2 hours or only one hour.
Now that you know how you can stretch out the life of your propane tanks and how to dispose of them once the fuel has run out, you can start to enjoy coffee and hot meals on the hiking trail or at a campsite without building a fire. We recommend a trustworthy refillable one so you can create less waste.
Bonus tip: Cook these 5 easy backpacking meal recipes on your propane stove on your next camping trip!