How Long Does A Standard Propane Tank Last?

Summer may conjure images of long afternoons spent outdoors, cold beer in hand, and the aroma of grilled meat and vegetables wafting up to the heavens. Yet this daydream can come crashing down if your propane tank runs out. To keep the backyard BBQ running smoothly, you should be tuned into how long your propane lasts and be ready to replace the tank when needed. The answer depends on the size of the tank and how often it's used.

The standard propane tank found on most gas grills holds about 20 pounds of propane, which translates to roughly 4.7 gallons of fuel. According to Weber, a full 20-pound tank typically provides about 18 to 20 hours of grilling time. For someone who grills once or twice a week, that could mean a tank lasts several months. Those who plan on barbecuing all summer long may need to refill or exchange tanks much more frequently.

You can even calculate the life of a tank. Start by converting its weight from pounds to gallons (subtract the weight of the actual tank, indicated as "TW" on the handle). One gallon of propane is equal to 4.24 pounds and contains 92,000 BTUs of energy. You'll need to divide the gallons' total BTUs by the hourly burn rate of your grill (the number of BTUs your grill burns per hour should be printed somewhere on the unit). If your propane grill burns 60,000 BTUs per hour, one gallon of propane will last about 1.5 hours.

Before you turn on the grill, you can quickly check how much propane is left in the tank by pouring hot water over one side and feeling for cold spots. Where the coldness starts signals the level of propane.

One of the easiest ways to extend a propane tank's lifespan is to avoid running the grill or other appliances at maximum heat. This is one of the common mistakes when grilling with propane, as high heat is probably unnecessary most of the time. Keeping the grill lid closed traps the heat and maximizes fuel efficiency. Also, a closed grill lid ensures even cooking for foods like chicken. When you're no longer using the tank, always turn the propane valve off to prevent leakage. The valve connection can be checked for leaks by pouring soapy water over it and turning it on (without lighting the grill). If bubbles start to form, there is a leak that is wasting fuel (and creating an unsafe grilling environment).

Propane does not degrade over time like gasoline, so unused fuel can last for years when stored properly. You may choose to keep a spare propane tank on hand so you don't run out in the middle of a BBQ. Storing a few extra propane tanks is considered safe, but they should always be kept outdoors or in a space like a shed that is away from your living area. Keep tanks upright, out of direct sunlight, and in a well-ventilated area.