Should You Choose a Propane or Natural Gas Generator?

Whole-home standby generators are run on either propane or natural gas. While some models accept liquid fuels, such as gasoline and diesel, they often provide a limited number of hours of operation when fueled that way.

Because fuel prices constantly fluctuate, choosing a supply that’s delivered to a home tank or piped in directly from a gas line is more cost-efficient. Additionally, natural gas and propane are both widely available for delivery and easier to store.

Propane and natural gas, while both gases, affect generator operation differently. Generators that run on only one of these fuel sources won’t operate correctly on the other, at least without conversion.

What’s the Difference Between Natural Gas & Propane?

Natural gas is light and delivered in its gaseous form, which means it’s piped directly from a main line at the street to your home. It’s as clean-burning as propane, but provides less heat density per unit than the other option.

Propane is heavier than air and is compressed into a liquid for delivery and storage. It’s pumped into a pressurized tank next to your home, which then supplies the generator with the necessary gas via a permanent line. Propane is also available in portable containers for use with smaller generators. Less propane is needed to provide the same power and run time as natural gas, but it also costs more per unit.

Questions to Ask Before Selecting

Do You Already Have a Gas Line?

Stick with the fuel you use for other home appliances. It’s rarely worth saving a few cents per unit of fuel to install a new gas line or propane tank.

If you don’t have a natural fuel source already connected to your home or business, figure out which is cheaper in your area. Installing a natural gas line could cost thousands of dollars, but if a gas line already runs along your street or to neighboring properties, the fees can run closer to a few hundred dollars.

Propane tanks can cost anywhere from $0 to $2,000 to install, depending on the deals your supplier offers. Free or low-cost tank installations typically come with monthly fees from the propane delivery company, which may make a natural gas line a better investment when it’s a nearby option.

How Many Watts Do You Need to Run Appliances?

In each cubic foot of propane, you’ll get 2,500 British Thermal Units (BTUs) of energy. That doesn’t just produce heat when burned, but also translates into the amount of watts it can produce. Natural gas only contains around 1,000 BTUs per cubic foot. With more than twice the energy density in the same volume of gas, you’re better off using propane for high-demand generator use. Generators just can’t provide the same wattage from natural gas as they can from propane, even when they’re designed to run on either fuel.

That’s also why you’ll find brands like Generac restrict their larger 6,000-watt-and-up generators to propane use only. Before assuming you can find a natural gas generator that fits your needs, add up the wattage you need to run essential appliances and see what manufacturers offer.

How Often Do You Experience Outages?

Propane is only delivered on certain days. During holidays and inclement weather periods, it can be challenging to schedule a delivery.

Since natural gas is delivered to your home through a buried and pressurized gas line, it’ll keep flowing steadily even during extended outages and frequent storm events. You won’t have to go outside to check how many gallons are left in a tank or worry about rising demand in the area adding delays to your delivery schedule. For that kind of peace of mind, it’s likely best to stick with natural gas for lower wattage demands that happen more frequently.

How Many Days of Runtime Do You Need During an Outage?

Your propane tank can only hold a limited number of gallons. Most hold between 300 and 1,000 lbs, and even the largest tanks will eventually run dry and need refilling. In areas that can experience power outages for weeks rather than days, getting a natural gas line installed eliminates the risk of running out of fuel. You will face a higher bill from your gas provider, of course, but you won’t need to call for an emergency delivery or go without power during a multi-day event.

Do You Need a Portable Solution?

Natural gas isn’t available in containers, while propane comes in every size from 1-lb tanks to 200-lb trailer-mounted options. You can grab a 20- or 30-lb propane tank with your portable generator for a short outage, a camping trip, or any other on-the-go power need. While most homeowners and business owners looking for whole-property power won’t need portable propane tanks, they’re the only option for travelers and RV owners who need to generate electricity without being tied to a permanent gas line.

Can Your Existing Meter Handle the Gas Demand of a Generator?

Generally, your home’s gas meter is sized to provide enough flow for the major appliances relying on it. Since a whole-home generator can need nearly as much gas as those appliances, you will likely need a gas meter that provides a much higher flow rate to prevent issues.

In homes with propane tanks, you’ll need to run a new line directly to it. If you’re concerned about running a propane furnace and generating electricity at the same time during winter storms and using up a smaller tank, consider upgrading to a larger propane tank along with the generator.

Need Help Deciding?

Every property is different. If you need help selecting and sizing a generator, our team at Budget Electric is here to help. We offer generator installation and maintenance services to homeowners and businesses across Southeast Michigan, including Wayne, Macomb, Oakland, Sanilac, and St. Clair counties.

Visit our website to learn more about our available options, or fill out our form to request a free installation quote.