Why Energy Efficiency Begins at Home

An energy-efficient home needs energy-efficient lightbulbs and air conditioners and refrigerators and other gadgets to fill it up. But it all starts with the structure itself. That’s why we recommend you take a good, hard look at your walls, ceiling, floors, windows, doors, roof, and electrical wiring as a first step towards decarbonizing your home life. (Embarking on a renovation? Heatmap has a guide for that.)

When you add air sealing and insulation, get energy efficient windows, or a cool roof that reflects heat back into the environment, you’re either preventing heat from entering or escaping. This stabilizes your indoor air temperature, thereby reducing your heating and cooling loads, which account for 55% of a household’s total energy use, on average. Making these improvements is not only good for the environment, it’s also a boon to your quality of life. Plus, it allows you to get the most bang out of one of Heatmap’s other favorite decarbonization upgrades: replacing your furnace with an electric heat pump, which operates most efficiently in a well-insulated home.

And lest we forget the electrification upgrades, they’re certainly a different beast than the aforementioned ways to seal up your house. But adding new electrical circuits is a prerequisite to installing energy-efficient appliances such as electric stoves, dryers, heat pumps, heat pump water heaters, or EV chargers. And depending how much space is on your electric panel, you might need to upgrade that too.

None of the investments mentioned here (often referred to as weatherization upgrades) will directly decarbonize your space. Insulating your attic won’t free you from fossil fuels, and installing new wiring doesn’t actually electrify anything in and of itself, although they will lower your energy-related emissions. But what these renovations do do is prime you to consume less energy at home just keeping yourself comfortable.

“The weather that you can expect to see where you live is changing over time and changing in a pretty unpredictable manner,” Michael Gartman, a manager at RMI on their carbon-free buildings team, told me. “The benefit of weatherization, unlike some of the other decarbonization measures that you might be thinking about, is it really just shelters you from whatever that change means over time.”

None of this sounds very thrilling, I know. These types of upgrades certainly won’t lead to the same oohs and ahhs that you’d get for buying a shiny new electric vehicle or induction stove. “You often can't see weatherization after it's been completed, and even if you can, I don't think many people are going to be taking guests into their basement and pointing at their floor joists and saying, look at all that insulation,” Gartman told me.

Probably not, but once folks spend some time inside your house, the benefits will become apparent in cooler summer days and cozier winter nights — and lower energy bills. “Even if it’s not sexy, that's something that you're going to feel every year that you're in your home,” Gartman said.

These upgrades that you’re considering — and the attendant reductions in energy use — will have impacts that ripple out beyond your home’s walls and onto the grid at large. After all, residential energy consumption makes up 21% of total energy use in the U.S., and 15% of total emissions.

“Weatherization can reduce peak demand on the grid, which reduces the likelihood of the grid going down in the coldest winter nights or hottest summer days,” Gartman told me. This makes the grid greener, too, as utilities often meet demand spikes by calling on fossil fuel sources such as gas plants, which can ramp up and down quickly. A smoother demand curve can thereby increase the share of renewables in the mix. And in the case that the grid does fail and the power goes out, a fully weatherized home is a safer home, protecting you and your family from the elements for as long as possible.

Depending on what weatherization measures you go with, as well as your specific circumstances, your savings could eventually surpass your upfront costs. The upgrade that’s most likely to pay for itself is air sealing and insulation, which can lead to energy bills that are 10% to 20% smaller, leading to net savings in just a few years. The Green Building Alliance says cool roofs — which are not suited to every environment — can also pay for themselves in as little as six years. And while complete window replacements are a particularly pricey upgrade, if you opt for storm windows that are installed on top of an existing window, you could see payback as soon as three years time post-installation.

No matter what you choose to do, the absolute best time to do it is when prices are low — and when it comes to energy efficiency upgrades, the discounts have arrived. “A lot of energy performance improvements to houses right now are on sale, and they're going to be on sale until the end of the decade,” Eric Werling, former national director of the Department of Energy’s Zero Energy Ready Homes program, told me. He’s referencing the $1,200 federal tax credit for weatherization, which is available now, and the home efficiency and electrification rebates that will be rolling out this year and next.

But even with this years-long sale, we know that the upfront costs can be tough to shoulder. So don’t feel pressure to drop thousands in the name of decarbonization right now. If you stay in your spot long enough, you’ll eventually need to undertake at least a few home improvement projects. “Anytime anybody does a renovation project or fixes a problem in the house,” Werling told me, “I implore them to think about, is there an opportunity for me to make improvements to the house that will pay for themselves in utility cost savings, but also improve the health and safety and comfort of the house that we live in?”

You’ll find the answer is often yes, and we encourage you to let your friends, family, and neighbors know about it. Because while we trust that you, as a reader, care deeply about the climate, you don’t actually need to give a hoot to benefit from energy efficiency upgrades. As Werling put it, “It's just not about energy, and it's just not about the climate. It's about your home.”