Everything you need to know about buying a backup generator
Standby vs. portable generators: Which is best for your home?
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Nothing makes us more aware of our dependence on electricity than a sudden blackout. You’re sitting alone in a dark room, mind abuzz with questions about how to handle your predicament. When was the last time you saved that project you were just working on? Do you even have candles, and where are they? Should you check Twitter for news, or does it make more sense to conserve your phone's remaining battery life for an emergency? How long do you have to wait until it’s socially acceptable to eat all your ice cream?
A combination of increasingly violent weather and aging infrastructure has been steadily amping up the severity and frequency of power outages for decades now—and there's no sign that trend is changing. If you’re looking to keep your home running through a blackout, a generator is your best bet. As with most cases, however, it’s important to choose the right tool for the job. And, in this case, the best solution for your budget.
Choosing the right type of generator
Before you can ask, "what size generator do I need," you need to ask what type of generator best suits your needs. There are four types of backup generators, each with their own unique list of pros and cons. For example, a standby generator keeps your whole home powered, but it’s an expensive proposition. There are other, less expensive options that can help take the edge off an outage.
Standby generators: Expensive but strong backup for the whole house
Also referred to as stationary or whole-house generators, these units run on either propane or natural gas and can efficiently power your entire home.
If the only reason you’re buying a generator is to provide total coverage during a power outage, a standby generator is your best bet—but it won’t come cheap. In addition to the high cost of the unit itself, you also need to factor in the price of on-site installation. While it’s impossible to determine the total bill up front, a good rule of thumb is to anticipate that installation will run you about twice the price of the generator itself.
Portable generators: Affordable and effective
Unlike standbys, portable generators are comparatively affordable, but they often require much more work.
These devices usually run on gasoline (although there are models that use liquid propane, natural gas, or diesel fuel) and have the advantage of being mobile. This means that you can take them along to job sites, where they can be effective for powering everything from tools to lights and more.
The advantage of portability does have its downside: These devices are often extremely loud and significantly less energy efficient than a standby generator. You also have to maintain a level of safety, and never run a portable generator in the house.
Inverter generators: Easy electricity on the go
Looking for a quieter generator that you can take along to a campsite? Inverter generators are the way to go.
This subset of portable generators runs on gas or propane and can be transported from place to place. They are also far more lightweight and quiet than standard portables.
With more sophisticated engines allowing for greater energy efficiency, inverters are ideal for juicing up everything from lights and air conditioners to electronics, smartphones, and more. That being said, inverters are better suited for a long camping trip than they are powering a house full of appliances.
Portable power stations: A quick fix for your smartphone—but not much else
If you don’t have the resources necessary for one of the generators we've already mentioned, but at the very least want to make sure you always have the use of your phone during a power outage, a portable power station is a good compromise.
These devices don’t burn fuel at all, and they are more like large, rechargeable batteries that you plug in. They might lack the raw power and longevity you can get from other types of generators, but they’ll keep your laptop and smartphone going during emergencies.
Powering your entire house: Standby vs. portable generators
One of the most common reasons people research generators is because they’re looking to power their whole home in the case of a power outage. If that’s the case, your options basically boil down to a standby or portable generator—an inverter could power your refrigerator, but not much else, and a power station won’t even keep your ice cream from melting (though you will be able to tweet about it).
- Typically cost between $500 and $1,500
- Can be moved and set up at different locations
- Its exhaust presents a carbon monoxide poisoning hazard—needs to be set up outside, away from the house, and therefore might additionally require weatherproof casing
- Requires more manual operation and monitoring
- More frequent fuel refills
- Not well-suited for days-long outages—typically more of a short-term solution
- The unit and installation typically costs between $10,000 and $20,000
- Wired directly into you home’s electrical system, so it can’t be relocated
- Requires less manual operation, often none at all
- Comes in weatherproof, insulated casing that makes it run much more quietly
- Typically uses a propane tank (can operate for weeks without refueling) or natural gas (doesn’t require refueling at all)
Manual or automatic? How your transfer switch affects your generator experience
Regardless of which type of generator you choose, it’ll need to be routed through a transfer switch first. Transfer switches are a relatively deep topic in and of themselves, but, in general, you’ll need to choose between a manual and an automatic system.
While portable generators are typically paired with a manual transfer switch, and a standby generator installation often comes bundled with an automatic transfer switch, the generator type is independent from the type of transfer switch—and the type of transfer switch greatly affects how you interact with your generator.
A manual transfer switch is significantly cheaper to purchase and install, but it requires manual activation during a power outage. You’ll also need to manually switch back to utility power once the outage is over, which means either monitoring the utility line itself or keeping an eye on your provider’s website for updates. As an additional bit of upkeep, you’ll need to run your home off the generator once every month or so to keep everything in working order.
Does this all sound like too much work? Then an automatic switch is for you. They’re more expensive to install and maintain (continuously checking the incoming line for outages does use a small, consistent amount of electricity), but it typically automates all of the steps outlined above.
The system detects any outages, swaps between the utility line and the generator when required, and then swaps back again and powers down the generator once the incoming electricity is stable.
Additionally, the generator’s monthly maintenance can be scheduled to occur on a date and time of your choosing—even activated manually via a smartphone app. Of course, if you’re pairing an automatic transfer switch with a portable generator, some of the process can’t be automated: You’ll still have to manually set up the generator outside and plug it into the inlet box, then turn it off and put it back in storage once the power is back on.
Prices were accurate at the time this article was published but may change over time.