The Half-Tank Rule Explained
Most people know that fuel is a key limiting factor during disasters or emergencies. Gas crises alone can cause cars to line up around the block. Add other disaster situations into the mix, and you have a mess. This is exactly why the half-tank rule is important.
Keeping your car or truck above the halfway point is one of the easiest ways to stay prepared. Oddly enough, many people choose to risk running out of fuel by driving all the way until the light comes on before looking to refuel. This reactionary refilling can cause big problems if there is any sudden delay or shortage of fuel.
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What is the Half-Tank Rule?
Always keep the tank in your vehicle at least half-full.
It is that simple. We will go further into the benefits and the drawbacks below, but this one rule can help you out tremendously in almost any emergency, disaster, or SHTF situation.
Benefits
Have you ever run out of gas? Most people have at some point. Hopefully, it was an easy remedy: have someone meet you with a jug of gas or hoof it down to the closest gas station. It ended up as an inconvenience that cost you some time.
Realistically, this is the best outcome. Running out of gas during a gas crisis would be worse. Running out of gas during a regional disaster while trying to evacuate can be dangerous. Running out of gas during SHTF can be life-threatening. All of these are risks of varying degrees, and they are all related to your gas tank. Keeping the tank at least half full helps mitigate these risks and can make disasters and emergencies have a lesser impact on you.
Another practical benefit of the half-tank rule is that you will never run out of gas again. Playing the game of chicken with the gas light in your vehicle means that just a few small problems can leave you stranded. With a reserve of half a tank rather than a gallon, you have a lot more cushion to absorb any problems with getting gas in everyday situations, not just emergencies. This can make you more reliable and timely, with fewer road incidents.
Drawbacks
Sure, there are some drawbacks to keeping half a tank of gas in your vehicle. For starters, you need to fill up twice as often. This eats up extra time often and can be inconvenient.
It is best to see this drawback as more of an investment. You are investing extra time now to be perpetually better prepared, and possibly save time in an emergency. In this light, the inconvenience does not seem so steep.
Sticking to the Rule
The half-tank rule is just that- a rule and not a law. Feel free to break the rule if you really must. I would prefer you keep driving rather than stop to top off with half a tank left in the bad part of town at 2 am.
Common sense and situational awareness should always prevail over any arbitrary rule you read about online. The rule is there to help guide your general preparedness and is not a sticking point to follow in every situation.
Bending the Rule
If your gas tank is small or if you are on the road a lot, you may have some issues sticking to the rule, regardless of what you do. One of the best ways to improve your gas preparedness on the road is with a simple gas can.
By keeping a full gas can with you, you can always have gas reserves and expand your resources. You will have to be cognizant of gas degradation, heat, and fumes, so you’ll want a quality gas can and some fuel stabilizer.
We’d recommend a Jerry can- but feel free to check out our entire gas can review roundup.
Half-Charge Rule
Electric vehicles (EVs) are slowly taking over the roads, but have an even larger issue when stranded without energy. Charging takes significantly longer than fueling up and can make getting stranded a nightmare.
Most EVs have smart navigation that will notify you well in advance if you attempt a trip that will come within 20% energy left. Murphy’s law is always hiding behind corners out there, and you can run out of energy just like gas if you get caught in traffic or surprised with other delays.
With home chargers, it can be easy to keep a charge full regularly, but on road trips and travel, you’ll need to make the call on when you charge. I like to look at the mileage remaining rather than the battery percentage level and make sure I have a considerable amount of miles to travel to the chargers.
One setting I suggest avoiding is the ‘scheduled charging’ most EVs have, which delays charging until non-peak energy hours to assist the grid and have lower energy costs. This sounds ideal until you need your EV for an emergency and find it not charged.
Running Out of Energy in an EV
You can’t simply walk up to a gas station and tote back a loaner gas can, and getting a charge isn’t as simple as jumping a traditional car when the battery is dead.
You’ll need to get a tow or get creative if you want to actually charge. To give you an idea of just how much energy you’ll need, a top-line Anker SOLIX Power Station holds 2048 Wh of energy- enough to get my Tesla Model 3 only 10 miles and would take several hours to transfer that energy.
You can also charge the battery using regenerative braking, which isn’t practical without another vehicle, but is still impressive with the efficiency of the system:
The Final Word
Fuel is a resource that will be scarce in almost every scenario we look at in our Threat List. If you are properly prepared for emergencies, you know that your vehicle is a huge asset, and keeping it prepared is a priority.
Knowledge and following a few self-imposed rules can be just as important as your emergency car kit. The simple half-tank rule can keep you on the road and ready to tackle the next obstacle.
Here are some more guides our subscribers have found helpful:
- Best Gas Cans for Prepping and Survival
- Best Fuel Stabilizers for Long-Term Storage
- Car Emergency Kit List | 23 Essential Items
Keep exploring, stay prepared, and be safe.
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I find the half full rule too inconvenient to be practical. So here is my way around it:
Daily driver: driven more miles, has a much bigger tank.
The BOV: driven weekly, smaller tank
As long as I do not let the BOV fall below 3/4 at the same time that the Daily Driver is below 1/2, I’m good.
Also BOV doesn’t go below 1/4 like ever, which is good for up to 100 miles on city mileage.
It takes about 10 minutes to direct siphon fuel from vehicle 1 to 2. 10 minutes can be a long time, but I reckon if 10 minutes or 100 miles isn’t doing it, I’m probably facing bigger problems.