Buying a Portable Generator – Features to Look For

Whether you're looking for emergency power, looking for a place to work, or considering recreational use, there are many factors to consider when purchasing a portable generator. To help you choose from the plethora of options, we've put together a list of what our team of professionals look for when they're in the market for a new product.

Buy a portable generator with enough power and outlets

When choosing the best generator for your needs, the first thing you need to know is the size of generator you want to buy. This means you need to understand how much power you need. Your refrigerator may only need 700 watts to run, but what happens when it needs 2100 watts to start? Note the starting watts required to run the equipment you intend to connect to the generator, and the "running watts" required once everything is working.

The other side of buying a portable generator involves what type of outlet you need. Smaller inverter generators usually have several 120V AC outlets and possibly a few USB ports. Once you get to 4000 watts, you'll start seeing 240V plugs pop up along with more 120V outlets. If you are considering having an electrician connect your generator directly to your panel, you will need a 240V plug. Since you're using your generator outdoors, look for one with a GFCI-protected receptacle.

You also have the problem of maximum output. Planning to hook up a generator to your home? A model with a 50A outlet can do more for you than a model with a 30A outlet. Keep this in mind when shopping. We have a Briggs & Stratton 8000W (10kW peak) generator in our shop. The largest receptacle on this unit is a 30A plug. This limits the power we can draw from it (30A x 240V = 7200W). The rest of the power comes from plugging into an additional 120V outlet.

Get generators with low total harmonic distortion (THD) and clean energy

Waveforms are important if you wish to run electronics such as laptops or lab equipment. Generally speaking, you need less than 6% THD to avoid damaging the circuit. Often referred to as "clean power" or "pure sine wave", it is a more stable and predictable voltage level. Pure sine wave generators tend to be more expensive and are used on lower powered devices.

By the way, battery inverters are not all low THD models. Some emit square waves. If you know you need clean energy, check out the specs.

Q: Is this for occasional use or continuous use?

Most generators include a several-year consumer warranty. For emergency power or recreational use, any reputable brand will do. However, if your crew needs a generator almost every day, you're better off looking for a model with a legitimate commercial engine. Not only will it fit better, but you're also likely to get a warranty that lasts for more than a year, not just 90 days or 6 months. The obvious downside is that these are usually more expensive.

Choose the Right Portable Generator Fuel Type for Your Needs

Gas and Natural Gas Generators Offer the Easiest Fuel Acquisition

Gas generators are by far the most common. Fuel is readily available, except during panics before and after major hurricane preparations.

Pro tip: Whether you store fuel in a tank or fuel container, be sure to winterize your equipment with a fuel stabilizer to counteract the effects of ethanol.

Likewise, natural gas generators allow you to hook up the unit to your home's existing natural gas supply. This means that, as long as the gas keeps flowing, you can have an almost unlimited supply of fuel for the generator when the power goes out.

buy diesel generator

If you are willing to pay for an upgrade, a diesel generator can give you better fuel efficiency. Buying a portable diesel generator will also cost you the carburetor. These always seem to get clogged at the most inconvenient times. If you're considering a whole house generator, you're thinking about diesel. Keep in mind that diesel may not be as easy to find as gasoline.

Another option is to look for a propane generator or a gas generator that can be converted to propane use. If you're looking for a greener fuel source and don't mind it being a bit complicated, that's another option.

Buying a Battery Powered Inverter Generator

The advantages of battery powered inverters such as the EGO Nexus Power Station and Ryobi Power Station are their ability to be charged from solar panels, quiet operation and no emissions. The downside is that they're expensive, charge slowly, and usually won't give you more than 3,000 watts or so. Outside of camping and tailgating, buying a portable variable frequency generator as backup power isn't currently a very practical option.

you may want a bigger gas tank

The larger the fuel tank, the longer the time between refueling. It's a given. Most generators have a fuel tank and can run for 7-9 hours at 50% load. If you use a lower percentage of available power, you will run longer; if you use more, you will run shorter. Given the choice between smaller and larger tanks, I'd go with the larger one. Remember, it will be heavier with a full tank.

There are also plastic and gas fuel tanks. There are pros and cons to both, and we have both types. In general, I like plastic because it doesn't have corrosion issues (thanks to ethanol again). However, this is not a make or break feature for me.

Buy a Portable Generator with Electric and Kick Start

If you really like pulling the recoil line on your engine, by all means skip the electric start. Seriously, though, an electric-start engine is great if you can save the extra money. When you're shopping for a portable generator, you'll find that most still use lead-acid batteries like cars do. However, there are some lithium-ion batteries running around.

Be sure to charge the battery before use. Most generators allow the charger to be plugged in to maintain charge between uses.

Consider paying for lower noise levels

When shopping for a portable generator, smaller models are usually less noisy. Some are even quieter than normal conversation levels. If you tailgating or camping in an area where generators are allowed, your neighbors will appreciate your consideration.

When you get into the 4000 watt class and beyond, there aren't many products in the "quiet" class anymore. One consideration comes down to fuel sources. Diesels generally produce more noise than similar gasoline models. Overall, the Honda generator is one of the quietest generators we have ever used. However, they come with a pretty high price point for this advantage.

EFI (Electronic Fuel Injection) eliminates clogged carburetors

Electronic Fuel Injection (EFI) is an important feature when buying a portable generator. It eliminates the need for a carburetor. A clogged carburetor is one of the biggest headaches for those who insist on keeping their maintenance on schedule. Of course, without maintenance, many problems can still arise, but a clogged carburetor is not one of them. Plus, your generator is easier to start in cold weather.

Carbon monoxide detection is now almost standard

Most manufacturers now include carbon monoxide (CO) detectors in their portable generators. Honda announced a plan to incorporate it across its entire lineup. These simply measure the carbon monoxide level near the engine and shut it down if the level gets too high. They usually work faster than those you can install in your home and are better at preventing illness or death from carbon monoxide.

Some people consider these "nasty" components when shopping for a portable generator. However, the industry seems to have signaled a shift toward including it in most new models.

Be aware that CO detectors can be spoofed. Make sure you point the generator exhaust downwind of the sensor, don't put it in a corner to avoid false readings.

Wheel generator or optional wheel kit

Generators are heavy, but not all generators come with a wheel kit. Some require you to purchase them separately, so make sure you know before you swipe your credit card at the till! You can buy two-wheel or even four-wheel portable generators. You can also buy aftermarket generator dolly kits to add wheels to models that don't have them.

We found installing the wheel kit to be fairly simple with basic tools. You can install a set of wheels to a generator in minutes. You may need a friend to help, or you can mount the generator on the edge of your truck's tailgate so you can access the installation area.

Get Hook Bars for High Storage

If you're buying a portable generator for commercial or industrial work, you'll most likely need to take it to a higher floor at some point. Generators with hook bars offer you a great advantage that saves you time and hassle.

Connect a Generator to Your Home

Hooking up a generator directly to your home is a very convenient way of getting emergency power. The best way to do this is with a whole house backup generator designed specifically for this purpose. These home generators are automatically turned on and off. Sure, they're more expensive than portable generators, but they've gotten cheaper recently.

You can also purchase a portable generator that can be hooked up to your home later. However, neither they nor whole-house generators are DIY jobs. You will need to install a transfer switch and have the job done by a qualified electrician.

There are other considerations as well. The first is to make sure that the generator you choose has enough power. If you don't have enough power to run the whole house plus a starting surge, you may need to flip some breakers to prioritize. If you're going to use a portable generator, you'll want to make sure you know where it is when it's running, and that you have a cable long enough to run to the transfer switch.

Need more specific advice when shopping for a portable generator? Check out our recommendations for the best portable generator options.

Now that buying a portable generator can be ticked off your list, make sure you also know how to maintain it so it's always there when you need it!