Choosing a portable generator : A how-to guide

Portable generators fall into two main categories: traditional generators and inverter generators. Let’s take a closer look!

The motors on traditional generators run at a constant speed, regardless of the load. Although people often use them for outdoor pursuits and off‑grid living, they’re also nice to have at home in case of a power outage. In this category, we recommend models equipped with a voltage regulator to keep the output voltage steady.

Main advantages : 

• They’re easy to transport because they’re often equipped with wheels and handles.
• The fuel tank ensures good run time.
• The circuit breaker protects power outlets from overloads.

Inverter generators are equipped with an electric module that adjusts the speed of the motor depending on the voltage required. These models are usually less noisy than traditional generators since they rarely operate at full capacity. They also have more sophisticated exhaust systems. 

Main advantages : 

• They’re easy to transport because of their small size.
• They produce less greenhouse gas emissions.
• They’re ideal for boating and camping.

A generator will generally provide between 1,000 and 14,000 watts of power. To calculate the amount of power you need, add up the running wattage of all the electrical devices and appliances that will be connected to the generator and add a safety margin of 20% to 25%. The running wattage is the amount of electricity needed to keep an appliance running and can usually be found on the appliance itself or in the owner’s manual.

You should also take into account each device’s starting power, meaning the power required during the first few seconds of use, which can be three times greater than the running wattage. This should also be specified on the device itself.

For example, running basic lighting, a refrigerator and a freezer requires between 5,000 and 7,000 watts. Adding an air conditioner, a water heater, a television and a few other appliances will increase your needs to between 15,000 and 20,000 watts, so you’ll want to weigh the benefits of each vs. the extra wattage they’ll require.

Here are a few more aspects to consider to make sure you get the right portable generator.

20-amp generators are the most popular: they’re generally compatible with appliances such as refrigerators and auxiliary heaters. 30-amp generators are ideal for powering recreational vehicles and various tools.

The last thing you want is to buy a device that’s so noisy you can’t hear yourself think. Choose a generator with a noise level of no more than 60 decibels, which is the level of a human voice.

The run time (autonomy) with a full tank of gas is generally between 5 and 11 hours, depending on the model. Keep in mind that run time is calculated based on average voltage and not maximum capacity.

If you plan to use your portable generator for camping or at a worksite, make sure it isn’t too heavy and that it’s easy to plug in.   

Throwing out your shoulder while pulling on a rip cord is a thing of the past. Many generators can now be started with the push of a button or even by remote control.

Some models are equipped with a battery charger adapted to several types of devices.

The fuel gauge shows you how long you have before the next fill-up.

This option allows the motor to run at lower speed when demand is low, which makes for better fuel efficiency and an extended run time.

The automatic power control prevents power fluctuations that could damage some appliances.

This safety feature shuts off the generator as needed: if the oil pressure or coolant level is low, for example, or if it’s overheating or otherwise unsafe to operate.

Look for the Canadian Standards Association (CSA) logo to choose a device certified in Canada and the U.S. for environmental compliance and safety.

Most portable generators are gas powered, but some models run on propane, natural gas or diesel. Some solar‑powered and battery‑operated devices have also recently come onto the market. Keep an eye out for interesting new options! 

Portable generators are very practical, but they need to be used with caution. Have an electrician hook your generator up to your home’s electrical system. Also, be sure to follow the safety tips and warnings in the user guide.

Each year, people are hospitalized as a result of improper use of a generator or carbon monoxide poisoning. All gas-powered devices must remain outside, in a dry, well-ventilated area, and be at least seven metres from your home. Never run your generator in your basement, garage or shed.

Before refuelling, always turn off the device and let it cool down. To avoid the risk of electrical overload, plug in your electrical devices and appliances one at a time, taking the generator’s maximum capacity into account. If necessary, use heavy-duty extension cords designed for outdoor use.