Generators are an essential backup power source, but knowing how long your propane generator will run is vital to keeping your family safe during an outage.

A propane generator run time calculator can help you determine how long your generator will last on a tank of propane. Just enter the size of your tank and the wattage of your generator, and this calculator does the rest.

With this handy-dandy propane generator run time calculator, you’ll be able to estimate your generator’s runtime before even leaving for the store. So please sit back, relax, and let me show you how it’s done.

## Propane Generator Run Time Calculator

A propane generator can provide fuel for your outdoor adventures with the right equipment. Propane generators come equipped either as 20-pound portable tanks or large Situ ones that must be filled at home but offer endless amounts of power.

As you might expect, propane is a popular choice for backup generators. However, it’s always good to be prepared and know how much of your fuel source will get used if the worst happens.

So how much gas do you need? The answer will vary depending on a few different factors, like the size of your generator. Other factors include:

- The load you are giving your generator
- The efficiency of the generator
- The model of the generator
- How long you are running your generator daily

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### Simple Calculation

To figure out how much propane you need for your generator, first find the fuel consumption rate for each hour. Multiply this by time spent using it and add some extra just in case.

- Total propane= (Propane you use per hour x hours) + contingency.

To do this right, you need to know how to calculate how much propane your generator uses per hour. If you want to know how much propane your generator will use per hour, all you need are some numbers.

For your calculations, you will need to make some basic assumptions about the efficiency of a typical generator. With a two-horsepower generator, you can produce up to 1000 watts of electrical output. It takes 10,000 BTU per hour of fuel to produce one horsepower. It takes 10,000 BTU per hour of fuel to produce one horsepower of energy.

Propane has a weight of 4.2 pounds per gallon, and its fuel value is 92,000 BTU per gallon.

#### Step One

You will first know the amount of horsepower you are using by calculating:

Horsepower= (watts/1000) x 2

For instance, you would require six horsepower if you have a 3000- watt baseload.

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#### Step Two

You are now required to understand how horsepower relates to BTU.

BTU= Horsepower x 1000

The scenario above will produce 60,000 BTU per hour for the 3000-watt load.

#### Step Three

After knowing all that, you can now determine how much propane it all equates to through calculations.

Gallons of propane= BTU/ 92,000

This will mean that you can run your generator with a 3000-watt load per hour with 0.65 (60,000/92,000) gallons of propane.

### Combining All The Calculations

I’m going to show you how combining these calculations can form one equation.

Gallons of propane used per hour= (watts/3000) x 0.65

You will find that 0.65 gallons of propane can weigh approximately 2.73 pounds. Therefore, a 20-pound cylinder can contain 0.65 x 20/2.73= 4.76 gallons. This generally means that your 3000-watt load generator can run for at least seven hours.

The calculations shown above are just an estimate and do not consider the efficiency of individual generators. However, it provides a useful starting point to work out how much propane your generator will use.

The most important thing to remember about your generator’s fuel is that it’s better to have some left than run out.

### Realistic Calculation

The amount of power you’re drawing from the generator may change depending on what’s happening in your home. You might have a baseload for refrigerators, sump pumps, and freezers, but then higher demands at night when using appliances like microwaves or washing machines.

The best way to calculate your propane usage is by considering both the baseload and peak hours. During these times, the amount you’ll need will be separate from one another but can still ultimately total up for an accurate prediction of what might happen with fuel consumption.

Therefore, you can opt for this calculation:

Total propane= (hours x propane use per hour peak load) + (hours x propane use per hour base load) + contingency.

## Frequently Asked Questions on Propane Generators

### How Long Will a Propane Generator Run On a 20 LB Tank?

Generators typically operate for five hours with 20 pounds of propane. The weight carried by your generator will determine how long it lasts before running out.

### How Many Hours Will a Generator Run on Propane?

You can expect your gasoline-powered portable generator to run for about 7.5- 12 hours continuously. Still, propane is the way forward if you want it running longer than that as they are more efficient. A typical portable natural gas unit will stay powered up for three weeks at a time with no need for refueling.

### Is It Cheaper To Run a Generator on Propane or Gas?

Propane generators are a popular choice for those who want to save money on their generator costs. Propane usually has lower prices than natural gas units, but you must consider how much fuel will cost before making this decision.

So, there you have it. A simple way to calculate how long your propane generator will run and a more realistic estimation of what that might be. Of course, this is just an estimate based on averages, and your results may vary, but now you at least have a starting point.

And remember, if you’re ever unsure or need help figuring out exactly what you need for your specific situation, you can always seek help. Stay safe, and don’t forget to stockpile those propane tanks.

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