What Is the Best Fuel for a Home Generator?

What Is the Best Fuel for a Home Generator?

Deciding what is the best fuel for a home generator is an important consideration during the purchase of a residential standby generator.

Here are some of the key attributes of the four most-commonly used fuels for residential standby generators:

Natural gas

Natural gas is a clean burning fuel and generally the choice of most residential standby generators in homes that already have a natural gas connection for heating and cooking. You can purchase the fuel from your local gas distribution companies. They will typically add a new meter and regulator (and often pipeline) for the generator. This does not involve the homeowner having to transport the fuel or fuel up your generator’s tank.


Propane has properties that are very similar to natural gas and it is relatively clean-burning. Unlike natural gas, which is available to households through gas pipelines, propane is available in compressed gas cylinders, similar to the ones widely used for cooking and heating. Residential standby generators that are fueled by propane are connected to these cylinders. Propane has a long shelf life and the propane cylinders are generally widely available and easily transportable.


Because diesel engines work by compressing air to ignite the fuel in the engine, starting diesel generators in cold weather can be problematic. Most manufacturers recommend including a glow wire or block heater with a diesel generator if the generator is expected to be operated at or under 32 degrees Fahrenheit. Diesel generators burn less cleanly, compared to propane or natural gas generators, and are generally considered to be noisier than their natural gas or propane counterparts. Diesel also degrades due oxidation and exposure to oxygen, high temperatures, moisture, certain metals and alloys, dust and dirt which can lead to soot deposits and clogged filters in the generator engine. Various additives are typically added to diesel to prevent the degradation and gelling of diesel when diesel fuel is stored for an extended period of time in a fuel tank.


Most portable residential generators are designed to run on gasoline. While gasoline is widely available, it has a shorter shelf life, is highly flammable and degrades over time, making storage a little challenging. Gasoline engines are less efficient, per unit of electrical energy produced, compared with diesel engines. During times of natural disasters, especially those that necessitate wide-spread evacuation, gasoline fuel for a portable generator might be difficult to come by.

Once you have decided upon your choice of fuel for your residential standby generator, visit our generator sizing calculator for a personalized assessment of you home power needs and for the right standby generator that will help you remain comfortable during the next power outage. Don't get left in the dark, contact AlltimePower™ today!

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