Propane tanks come in many different shapes and sizes. They are listed in both pounds or gallons. The listed weight of a tank is the weight of the fuel in the tank and does not include the tank itself. Different size tanks are used for different applications with different appliances, and the amount of time each lasts depends on how often they are used and how much fuel the appliance requires.
These are the small, hand-held canisters that can be purchased at many types of stores. These 0.454kg. canisters are designed for use in small appliances like portable camping stoves and lanterns. They don't contain their own valves and connect easily to their appliances, usually using a threaded fitting.
20 to 40 Pounds
Smaller tanks in the range of 20 to 40lbs. are primarily designed for use on barbecue grills and other large yet portable camping/cooking appliances. They can also be hooked up to RVs. Twenty pound tanks hold around 4 gallons, 13.6kg. tanks hold 3.18 and 18.1kg. tanks hold 10. These are the most common of the larger size tanks and can last for 8 to 40 hours, depending on the number of burners and BTU output of the grill.
60 to 100 Pounds
These size tanks are noticeable taller than the stocky-shaped 20- to 18.1kg. tanks. The tank and gas combined can weigh up to 77.1kg. when filled. Tanks containing 27.2kg. of propane usually equals 15 gallons, and 45.4kg. tanks hold 25. Their BTU output can be more than 2 million. Along with cooking and heating, these tanks can be used for tools like acetylene torches.
Large Home Tanks
The largest propane tanks are designed to provide full-time fuel for homes and other buildings. They contain from 250 to 1,000 gallons of propane. They can resemble oil and gas cars on freight trains, often need to be transported by a vehicle and should be installed by a professional. The amount of time these last can vary, especially depending on the home's size and insulation; they can last anywhere from a few weeks to months.