Instead, she and other experts recommend investing in more environmentally friendly backup power sources, namely solar and batteries. These units can range from portable solar power banks to larger home installations involving rooftop solar panels connected to battery storage systems. Depending on the technology and how much energy you use, some of these systems can power an entire home for several days in the event of a power outage. They can also offer year-round benefits, including reduced utility costs.
“A gas backup generator for your home is like an insurance policy that is worthless until you have a really bad day,” said Mark Dyson, managing director of carbon-free electricity at energy think tank RMI. “Other solutions we want to explore, like solar plus storage, for example, can save money every day and also provide a backup solution in an emergency.”
We looked at the differences between solar batteries and traditional fossil fuel generators. Here’s what you need to know.
What are your options?
The size of a generator or backup battery depends on how much power you need, said Noah Kittner, an energy systems expert and assistant professor at the University of North Carolina at Chapel Hill.
Fossil fuel generators:
This is the oldest and most common type of generator. They run on different types of fuel, including diesel, propane, and natural gas, and can be portable or permanently installed.
You can use them to power various electronics, larger appliances, and entire homes. The number of appliances a fuel generator can power depends on its size, power output, and how much fuel you have.
Stand-alone batteries:
Batteries also come in a variety of sizes and can be portable or installed. Smaller batteries may be enough to run a small electric fan, charge cell phones, or power a radio.
For a refrigerator, you’ll need at least eight to 12 hours of backup power, Kittner said. Common rechargeable lithium-ion batteries designed for homes can usually provide that amount of power.
Standalone batteries have a limited lifespan, Dyson said. Even the largest ones can run out pretty quickly if you use them to power devices that draw a lot of power, like stoves or air conditioners. That means if you use these batteries during a power outage, once they run out, they could be completely dead. you will have to wait for the power to come back on or find another way to recharge them.
Solar powered batteries:
Portable batteries, which also vary in power output, can be equipped with small solar panels, allowing them to be charged without plugging them in. If the battery is completely discharged, recharging using solar energy can take several hours.
You can also have larger systems with rooftop solar panels connected to battery storage systems. These residential installations can benefit homeowners even when the power is not out, said Z. Smith, principal and leader of sustainability and building performance at EskewDumezRipple, an architecture firm with offices in New Orleans and Washington, D.C.
“In economic terms, a battery and solar system allows you to make a profit at all times, whereas the generator is a dead loss and its profit is only there during the power outage,” Smith said.
How do they work?
Rooftop solar and storage systems are directly connected to home electrical systems, Dyson said. Most portable batteries connect directly to individual appliances or through extension cords. Similar to a fossil-fuel backup generator, some larger batteries can be connected through transfer switches, which connect them to your electrical panel, he said. In the event of a power outage, the switch allows your home to draw power from your backup source instead of the grid.
Backup power sources can be more effective if your home is well insulated and weatherproofed to prevent air leaks, Dyson said.
No matter what type of backup power you have, be mindful of your energy usage during power outages, Burke said.
“You generally need to be judicious about how you use energy in your home,” she said. “You wouldn’t run the dishwasher, the washer and dryer, all the appliances in the house at the same time. Those are emergency situations.”
Avoid fumes
Avoiding harmful and polluting fumes is one of the main benefits of not using fossil fuel generators.
These generators produce exhaust gases that contain dangerous pollutants, including sulfur dioxide, nitrous oxide, particulate matter, and carbon dioxide. Their operation can also release carbon monoxide, an odorless, colorless gas that can kill people within minutes if it builds up indoors. Generators also tend to be noisy.
“One of the biggest concerns is local air quality,” Burke said. “Imagine if a neighborhood has no power and almost every home has some kind of fossil fuel generator running all the time, it’s incredibly hot and humid — all of that turns into very harmful ground-level ozone, which causes serious respiratory problems.”
You should never use fossil fuel generators inside your home or garage, even if the windows are left open. Place portable generators at least 20 feet away from any residence, open window, or garage with the exhaust directed away from the dwelling, according to the Centers for Disease Control and Prevention.
“It’s critical that people understand that if they do this kind of informal thing like getting a gasoline generator and keeping it powered and putting it on their porch or something like that, you’re actually introducing what could be a source of danger into or adjacent to your home,” Smith said.
Solar generally costs more
The cost of any type of generator will depend, in part, on its size and technology, but prices can also vary between similar models.
For example, a 5,000-watt portable diesel generator, a common size that could be used for small homes, apartments and RVs, can cost anywhere from $500 to more than $5,000. A solar-powered battery model that can generate 5,000 watts continuously costs about $4,700.
If you want a more robust, permanent form of backup power, it will come at a cost. The initial price of installing a residential solar array and battery storage system will be significantly higher than a similarly sized gasoline or diesel generator, Dyson said. But these systems can save homeowners money in the long run, and there are federal tax incentives and, in some cases, no-down payment financing options to help lower the cost of the technology and installation.
“If you just look at the value of solar, in most parts of the country it pays for itself pretty quickly,” Dyson said. Battery storage, he added, is also becoming more cost-effective.
At the same time, the cost of maintaining and fueling standard generators can add up over time. Without regular maintenance, your generator may not be running when you need it.
“The difference is that the diesel generator sits there and degrades, whereas the solar plus battery system gives you ongoing value and adding a battery can give you resiliency,” Smith said.