Portable Generator Buying Guide

Every home should have a backup power generator in the garage for many reasons. Hurricanes, snowstorms, wildfires, brownouts, cyber-attacks, or just plain old Billy backing into the utility pole again - all pose risks to the fragile power grid we all rely on. Being left without power during an unexpected blizzard clinging to 10 layers of winter clothes like Survivorman may have its charm. But you better be prepared if you want to be able to keep your house running during emergencies. You don't want to run out and buy a generator after disaster strikes - you want to be prepared ahead of time.

With so many generator choices on the market, which power generator do you actually need? This guide will provide a thorough breakdown so that you can make a smart decision to buy the perfect home generator for you.

Types of Generators

There are many different types of generators, each offering their own advantages and drawbacks.

Portable Generators

Portable generators use gas, propane, or other energy source to spin magnets and generate electricity, allowing you to power your appliances during times of need. These generators can be rolled around using wheels and typically produce between 1,000 and 15,000 watts. Conventional generators are the most popular form of backup power.

Conventional portable generators are good for: homes, job sites, industrial/commercial backup

Inverter Generators

Inverter generators are similar to conventional generators, except for a few key differences. Conventional generators contain the combustion engine and the electric generator as separate units. An inverter generator combines them into a single unit so that the combustion engine is also an electric generator.

In summary, inverter generators:

1. Produce "cleaner" AC power by first converting it to DC, and then back to AC. This helps protect your sensitive electronics like your laptop or TV from power surges.
2. Are more fuel efficient because they can adjust the speed of the motor to match power demand. Conventional generators operate at a standard speed (typically 3600 RPM) regardless of how much power is being drawn.
3. Are significantly quieter when running at varying loads. At maximum load, inverters are just as loud as conventional generators.
4. Weigh a lot less than conventional generators.
5. Are more expensive than conventional generators.

Inverter generators are good for homes, camping, tailgating, RVs/Campers, or any other place that needs to power sensitive electronics like laptops, computers, printers, etc.

Solar Generators

Solar generators work on the photovoltaic principle to capture light from the sun, convert it into electricity, and store it in the battery for use. Solar generators produce anywhere from 100-2500W of power, depending on model, and typically come with one or several solar panels used to charge the solar generator. Optionally, you can charge the solar generator using your home outlet. The amount of energy you can store in a solar generator is measured in Watt-hours.

Solar generators are good for: camping, boats, powering small home appliances, charging cell phones, powering laptops and small electric devices.

Standby Generators

Standby generators are stationary systems designed to connect to your home's propane or natural gas supply line and provide automatic power in case of an outage. These generators are some of the most expensive but also most powerful ones, providing up to 25,000 watts of reliable power. This is more than enough to fully power a home for an extended period of time.

Standby generators are not meant to be refueled. They work completely passively, kicking in as your power goes out, and staying on until your grid is back online. Most are equipped with an automatic transfer switch to easily switch between propane and natural gas as needed.

Standby generators are good for: powering your entire house, potentially indefinitely

Generator Features

Generator Outlets

The main thing to consider, aside from generator power, are the outlets offered by the generator. Do you use regular household plugs? Look for the 5-15 or 5-20 outlets. Need to connect your RV/Camper? You might need the TT-30, 5-30, or L5-30 outlet. If your RV/Camper has a plug that's different from the generator, you can always buy an adapter that converts, for instance, TT-30 to L5-30 or vice versa. Here's a handy chart that helps break it down.

You may notice plug names like "5-20R". The "R" explicitly states that it's an outlet, while 5-20 does not. For all intents and purposes, treat 5-20R and 5-20 the same when considering generator outlets.

Electric/Remote Start

If repeatedly start pulling your generator in freezing weather is not your cup of tea, consider investing in a generator with an electric starter. The electric start allows you to easily start your generator by pushing a button. For a more advanced option, look for a generator with a remote start which allows you to do the same thing but from the comfort of your home or RV.

Fuel Gauge

During prolonged periods of power outage, it is useful to be able to discern the remaining fuel level without the need for a flashlight.

CO Shutoff Sensor

Safety features play a major role in a portable generator buying decision. Some of the nicer models feature a carbon monoxide (CO) sensor, which shuts them off if levels around the machine become unsafe. Some of the premium brands offer low CO motors along with the shutoff sensor. Carbon monoxide poisoning from generators is responsible for dozens of deaths annually.

Automatic Oil-Level Shutoff

If the oil level reaches a low threshold, this feature shuts the generator down, preventing a catastrophic engine failure.

Fuel Sources

While most portable generator run on gasoline, there are alternative fuel equipped models out there. Manufacturers offer propane, natural gas, and diesel. Some producers offer adapters and conversion kits.

Portable Generator Safety

• Never run a gas-powered generator inside a dwelling under any circumstances. 
• Do not store fuel near the machine.
• Never utilize typical household extension cords outdoors. Purchase a heavy-duty generator cord and run it inside to a surge protector.
• Operate the machine at least 20’ from your dwelling and face the exhaust away.
• Do not operate a generator outside in precipitation. Purchase the manufacturer’s approved canopy, or operate in a carport.
• Never leave a portable generator running unsupervised.

Miscellaneous Purchase Considerations

The biggest mistake buyers make when purchasing a portable generator for disaster preparedness is waiting until they absolutely need one. As an example, hurricanes create buying frenzies for everything from portable generators to gasoline to fuel cans.

Do you really want to brave hours-long lines and then attempt to assemble and set up a portable generator with no power? Does pull-starting a portable generator in 60 mph winds, dangerous lighting, and torrential downpours sound appealing? Disaster preparedness is a proactive game.

If you may need to utilize the generator sporadically or unpredictably and desire to leave it gassed-up at all times, purchase a bottle of fuel stabilizer and add it to your tank. Hurricane season comes and goes each June through November, so I simply run all of the fuel out of the machine before storing it for the off-season. If you leave unstabilized fuel in them for months or years on end, the gasoline ruins the carburetor, and they won’t start when you need them the most, and they will require an expensive repair.

Keep a spare spark plug and plug wire on hand. Don’t forget, these are simple machines. If you can keep a lawn mower or snow blower running, you are capable of maintaining a portable generator.

Tips

• Never start the generator with anything plugged into it
• When using propane, prime the engine by lightly pulling the starter a few times before initiating a full start

FAQ

What is the Difference Between Watts and Watt-Hours?

Watts is the rate at which power is flowing per second. A 50 watt light bulb needs constant 50W of energy per second to stay on. A 500 watt solar generator is able to supply a maximum of 500 watts per second of energy from its battery. Watt Hours (Wh) specifies the storage capacity of the battery. A 1000Wh battery can produce 1000 Watt stream of power for 1 hour (or 3600 seconds).

What is the difference between Starting (Surge) Watts and Running (Rated) Watts?

Some motor-driven products like fridges and circular saws require extra power for a few seconds to start. The starting watts specifies how much power the generator can output for those few seconds to help start those appliances. Running, or rated watts, specifies the continuous power that the generator can supply over long duration. Even though a fridge might consume 700W during normal operation, it might require as much as 2200W to start.

My generator doesn't have a 30 Amp RV outlet. Can I still power my RV?

Yes, you can power your RV using a non-RV-Ready generator using the standard 20 Amp 5-20R outlet but you need to get an adapter to make it work. Obviously, you will only be able to draw a maximum of 20 amps instead of 30.

Which fuel source is cheaper, gasoline or propane?

Watt per watt, propane is about 2x more expensive than gasoline. Propane will also typically provide 85-90% the wattage of gasoline. Keep in mind that those extra 200W could be the difference between starting your RV air conditioner or not.