A new backup plan: Why it’s time to replace standby generators with batteries

Back-up generators emit greenhouse gases and toxic gases, harming the environment and our health. Back-up batteries don't. We need policies nationwide that will make batteries the easy choice for homeowners. 

Jamie Friedman

Policy Associate

Forty propane tanks. That’s what my family needed during Hurricane Sandy, a 10-day power outage, to keep just the essential parts of our house running for part of each day. Our propane-powered backup generator, the large chunk of metal that sits outside our house making a loud engine noise, had been the only solution available in the early 2000s. And, as anybody who has been through a prolonged power outage knows, the novelty of sitting by candlelight wears off pretty quickly.

We weren’t alone: In 2015, nearly 20% of all single-family homes in the U.S. had a backup generator. The size of the generator market is even larger today, and in 2019 generator companies reported that sales have “skyrocketed” with no signs of slowing down. It’s the result of climate-related natural disasters becoming more frequent, and the likelihood of week-long power outages increasing across the country. From the East Coast with its hurricanes and snowstorms, to the West Coast with its wildfires, and tornado country in between, there is hardly a section of the U.S. that is not prone to grid-disrupting natural disasters. And in 2020, with most of us working from home, a backup plan that guarantees reliable electricity has become even more essential.

What I didn’t know until recently was how much damage that backup generator does to both the environment and the health of those around it. Three common generator fuel types — diesel, propane, gasoline — all emit carbon dioxide, a greenhouse gas, and carbon monoxide, which can be deadly. The exhaust from diesel generators also contains more than 40 toxic air contaminants, including known cancer-causing substances, as well as air pollutants like nitrogen oxide, which contributes to the formation of smog. With millions of backup generators in use across the U.S., the total carbon footprint and impact on air quality is enormous. Not only that, but by contributing to climate change, generators feed into the cause for such extreme natural disasters in the first place.

Between 2005 and 2017, more than 900 people in the U.S. died from carbon monoxide poisoning from portable generators, with another 15,400 needing emergency room treatment. Most of these cases were a result of generators being set up incorrectly indoors, but there are cases from outdoor generators, too. In some storms, more people have died as a result of carbon monoxide poisoning from their generator than directly from the storm itself, as was the case for Hurricane Irma in 2017.

No one who uses a backup generator wants to put their family at risk. So if there was a safer and cleaner solution available, it would make sense to make the switch as soon as possible.

Backup home batteries can be that safe and clean solution.

Backup home batteries can power your home with renewable energy when paired with solar panels. Unlike generators that need to be refilled with dirty fuel every few hours, a combination of on-site solar panels and backup batteries can theoretically supply power indefinitely. Even during a blizzard, solar panels may not work as efficiently covered in snow, but coupled with a battery they can still power parts of your house through a power outage. And, as with most emerging clean energy technologies, they are continuing to improve and become more efficient, powerful, and affordable. With none of the detriments and most of the benefits of a generator, the backup battery should be an easy choice.

Yet for most people, there has been one significant obstacle: the cost. Compared to generators, batteries with a solar energy system can have expensive upfront costs, even if they end up being more affordable in the long run. Smart public policy can bring the price down in the short run while helping the battery storage industry to achieve economies of scale, bringing prices down for everyone.

This year, in the first policy of its kind in the country, state utility regulators in Vermont approved an energy storage program that would allow customers to lease a backup battery. The program allows customers to lease a Tesla Powerwall for 10 years at $55 a month, as opposed to paying $6,500 outright. And even when the grid is up and running, having a battery and solar system attached to the grid can provide flexibility by allowing you to store excess energy or sell it back to utility companies. A second energy storage program in Vermont gives customers who already own a backup battery up to $10,500 if they allow utility companies to draw from its stored energy.

Policies like Vermont’s are a step in the right direction, and all states should pursue similar or even stronger programs that incentivize homeowners to choose battery storage. In addition, states across the country should set stronger emissions standards that discourage the production of high-emission generators.

The backup generator industry is growing faster each year, and with it the stakes for our environment and health are becoming higher. There’s no better time than the present to make the switch to backup batteries and renewable energy, so that when the next prolonged power outage comes, we can be prepared without worrying about the many scary side effects of dirty fossil fuel-powered generators.

Photo credit: Bryan Alexander via Flickr (CC BY 2.0)


Jamie Friedman

Policy Associate

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