THE DEFINITIVE GUIDE
Propane. Stored energy you can count on.
Tank types, BTU math, fire-code placement, regulator matching, refill economics, appliance options, and safety. Six in-depth guides covering everything a household needs to know.
By Dan Whelan, founder of New World Survival
Researched from government agencies, university extension services, and other published sources. See our sources
WHY IT MATTERS
A fuel that waits until you need it.
Gasoline degrades in weeks without stabilizer. Diesel grows algae in months. Propane is chemically stable indefinitely. A tank filled today burns identically in five years, ten years, or thirty, provided the tank itself is sound. For a household building energy resilience, that stability changes the math.
But "the fuel lasts forever" is only half the sentence. The tank does not. Steel corrodes. Valves seize. O-rings degrade. A propane strategy means understanding both the fuel and the container, and maintaining the container so it matches the fuel's patience.
Chemically stable
Propane does not oxidize, gel, grow microbes, or lose energy density in storage. It does not gum carburetors. The fuel is as good as the day it was refined, as long as the tank is maintained.
Works below freezing
Propane boils at -44 °F (-42 °C), so it still turns to vapor on a freezing winter day. How well a tank keeps up in deep cold is its own question, covered in How Long Propane Lasts.
One fuel, many uses
Camp stoves, indoor-rated heaters, whole-home furnaces, water heaters, clothes dryers, generators, and propane lighting all run on the same fuel from the same tank. That simplicity matters when you are managing a disruption.
THE BASICS
What you need to know before you go deeper.
Liquid in the tank, gas at the burner
Propane sits in your tank as a liquid under pressure, with a layer of vapor above it. When you open a valve, the vapor flows to your appliance. As vapor leaves, the liquid boils to replace it. No pump is needed. A regulator steps the pressure down to a safe, steady flow.
Heavier than air
Propane vapor is roughly 1.5 times heavier than air. If a leak occurs, the vapor sinks rather than dispersing upward. It pools at floor level, in basements, in crawlspaces. This single fact drives most propane safety rules: store outdoors, never in enclosed spaces.
The 80% rule
Tanks are never filled to 100%. The top 20% is left as vapor space so the liquid has room to expand as temperature rises. Without that cushion, thermal expansion could raise the pressure enough to open the relief valve and release gas.
Two kinds of tanks
DOT cylinders are the portable tanks you carry or move (1-lb to 100-lb). ASME tanks are the stationary tanks permanently installed at a home (120 gal to 1,000+ gal). Different regulations, different inspection cycles, different filling procedures.
The BTU formula
One gallon of propane holds about 91,500 BTUs. Every appliance has a BTU-per-hour rating. Divide the tank's total BTUs by the appliance rating and you know how many hours of runtime you have. That is how you plan.
Safety is straightforward
Store spare cylinders upright and outdoors, never indoors. Check connections with soapy water. Know the smell: suppliers add a strong odorant so a leak can be noticed. Never use a camp stove or other outdoor appliance indoors. Install a battery-powered or battery-backup CO detector. The rules are simple. Following them is the whole job.
EVERYTHING YOU NEED TO KNOW
Six guides. One complete propane education.
Each guide goes deep on one topic. Start wherever your question is, or read them in order for the full picture.
Tank Types and Sizes
DOT cylinders vs. ASME tanks. OPD valves. Tare weight. The size range from 1-pound camp canisters through 500-gallon residential tanks, with capacity and use cases for each.
Read the full guide
How Long Propane Lasts
The BTU formula, a runtime reference table for common appliances, the 80% fill rule explained, cold weather effects on vapor pressure, and how to calculate your own household fuel needs.
Read the full guide
Storage and Safety
NFPA 58 placement distances. Tank elevation and rust prevention. Transport rules. Leak detection. Carbon monoxide prevention. Fire safety. Cylinder requalification dates.
Read the full guide
Getting Propane
Refill vs. exchange vs. bulk delivery. The real cost math (including exchange underfilling). Refillable 1-pound canisters. Seasonal pricing. Delivery contracts, minimum fills, and keep-full programs.
Read the full guide
Regulators and Connections
Single-stage, two-stage, and high-pressure regulators. Changeover valves for dual-tank setups. Natural gas to propane conversion. Matching the regulator to the appliance.
Read the full guide
Propane Appliances
Every appliance propane can power: cooking, heating, water heating, generators, clothes drying, lighting, and outdoor living. What works during outages, what does not, and what to look for.
Read the full guide
CONNECTED GUIDES
Propane connects to the rest of your energy plan.
Heating During Outages
Using propane and other safe options when the power goes out. Which heaters are rated for indoor use and how to run them safely.
Generators
Dual-fuel and tri-fuel generators that run on propane. How propane eliminates carburetor gumming at a modest power tradeoff.
Wood Heat
A complementary heat source that uses no propane and no electricity. Together, propane and wood cover the full heating spectrum.
Passive Heating and Cooling
Reduce the load on any fuel source. Insulation, thermal mass, and air sealing make every BTU of propane go further.
Power Outage Action Plan
The step-by-step protocol for what to do when the power goes out. Propane appliances are part of the plan, not a substitute for one.
Energy Hub
The full Energy Preparedness section. Solar, battery systems, generators, heating, cooling, lighting, and the Energy Ladder framework.
Sources and standards
Safety claims, clearance distances, and regulatory requirements throughout these guides trace to primary sources:
- NFPA 58 (Liquefied Petroleum Gas Code): tank siting, placement distances, safety requirements
- 49 CFR Part 180 (DOT): cylinder requalification intervals and procedures
- CDC: carbon monoxide poisoning prevention data
- CPSC: generator safety, portable heater safety, CO fatality data
- DOE: propane energy density, combustion characteristics
- Ready.gov: backup fuel source recommendations for power outages