Home of the Future: How to electrify your life

Jeff St. John . 6 February 2023

Here's an introduction to Canary Media's special series, Home of the Future: How to electrify your life.

The future of all-electric, high-efficiency, grid-interactive homes seems near at hand from the floor of the CES 2023 event in Las Vegas. The massive annual extravaganza has long been the showcase for high-tech consumer electronics, including the latest in ​"smart" home automation systems, energy controls and electric appliances.

Take the home product lineup from global electric equipment and technology giant Schneider Electric, which includes batteries, EV chargers, hybrid inverters and the latest iteration of its smart electrical panel. Much like similar smart panels from global competitors like Eaton or startups like Span, it allows homeowners to monitor and control electricity demands at the circuit level via smartphone app, switch between grid and battery power and keep electrical loads under the limits of household wiring or utility grid service.

Individual Wi-Fi-connected ​"smart plugs" add even more discrete control. Schneider's CES-award-winning app and energy disaggregation technology from Sense, a startup partner, can help analyze data and automate the actions of all these devices to reduce utility bills, keep homes powered during blackouts or even sell home-generated and stored power back to utilities

Maria Virginia Olano . 10 February 2023

Canary Media's chart of the week translates crucial data about the clean energy transition into a visual format. Canary thanks Sense for its support of the Home of the Future series.

Americans are buying more heat pumps for their homes than ever before. U.S. annual sales rose above 4 million units for the first time in 2022, outpacing sales of gas-powered furnaces.

Julian Spector . 10 February 2023

Canary Media thanks Sense for its support of the Home of the Future series.

In the early weeks of 2023, electric induction cooking emerged as a flashpoint in the culture-war skirmish du jour, an unexpected turn for a cooking appliance that's been around for years.

To be clear, the White House isn't trying to take away anyone's gas stove, but some progressive cities and states are working to get gas out of homes entirely, for the sake of the climate and for people's health. But before that can happen, there has to be a widely accessible alternative. And the induction-stove sector still has plenty of growing to do.

The basic induction technology is well established; these stoves boil water much faster than gas stoves and they offer far more granular heating control than is possible with combustion.

But there are a number of logistical challenges to overcome before induction cooking can be adopted by the mass market. Here are the key obstacles to widespread induction-stove adoption, followed by some of the solutions, including one major technological innovation that will make a huge difference.

Generally, when you buy an appliance, you know how much it’ll cost you. Items that require specialized installation may come with an extra fee, but that's communicated upfront. That's not the case with induction ranges.

An induction stovetop usually needs at least 40 amps allocated on the home breaker box, and a high-voltage plug on the wall to feed it. If you don't have enough space left on your breaker box, or you don't have a high-voltage plug within reach of your oven spot, the costs of the electrical work to actually install induction can spike. And it's hard to know how much extra work you’ll need without expert consultation.

"You can't just do it — you have to pay an electrician to figure out what it's going to cost," said Weldon Kennedy, founder of Channing Street Copper Company, an induction-stove startup.

Besides the uncertainty around induction installation, the high cost and extended timeline also impede adoption.

A relatively minor installation may still punch through drywall or masonry, incurring additional work to patch it up. But if the stove's consumption exceeds what the electrical panel can provide, the panel upgrade alone can cost thousands of dollars, and it may take a while to find an available electrician.

In some cases, you may need to upgrade your home's service from the distribution grid, which means the electric utility gets involved — and passes you the bill for their efforts. And in extreme cases, one home's desire for an electric stove can push the neighborhood grid over the limit, requiring installation of a whole new transformer. That unlucky homeowner could face a charge of tens of thousands of dollars if they decide to go through with it.

That's an untenable tab to install an appliance that itself only costs a couple of thousand dollars.

It's not a random home cook's job to worry about whether the grid has enough electricity to meet demand. But in aggregate, mass adoption of induction cooking poses a risk to the workings of a clean energy grid.

Take California, which is getting rid of fossil-fueled electricity by 2045, and moving toward carbon-free buildings, too. The Golden State already struggles with power shortfalls in the post-sunset hours, when solar production drops off just as people get home from work and start using more energy. Supplying those evening hours — known as the ​"duck curve" problem in grid-planning circles — will get a whole lot harder if millions of homes need a simultaneous surge of power to cook dinner on induction.

Without some coordination to minimize grid stress, utilities will have to spend more money to meet demand for induction cooking, and those costs will trickle down to consumers one way or another.

Extreme weather — fueled by climate change — topples electric grids around the country on a regular basis. When the grid goes down, homes that run stoves on electricity will lose the ability to cook, if they lack backup power.

That could be jarring for people who are familiar with gas stoves as a way to cook through an outage. Granted, some gas models rely on electricity to actually ignite the fuel, and combusting gas indoors without functioning ventilation is bad for your health.

People can ride through a grid outage by equipping their homes with backup generators, solar-charged battery packs or certain electric vehicles like the Ford F-150 Lightning — but these require thousands of dollars of investment. Without these or other solutions, induction stoves are only as strong as your local electric grid.

Setting aside outsize installation costs, induction cooktop products still tend to come at a market premium.

"For cooktops and portable countertop hobs, there are affordable options, but for full-sized ranges, the majority of available models are in the higher price ranges," said Noah Cordoba, who analyzes kitchen electrification at the Building Decarbonization Coalition. One of the most affordable full-size induction ranges is made by Frigidaire, but it still retails for more than $1,000.

These challenges aren't insurmountable. Much like rooftop solar or battery storage, induction stoves are the hardest to get in the earliest stages of mass adoption.

Already, startups and legacy appliance makers are moving fast to make induction products more accessible and desirable. They’re trying out all sorts of design upgrades, but one of them stands out for how many problems it could solve single-handedly. The idea: make induction stoves with batteries.

Adding energy storage to induction stoves will let them more easily slip into existing infrastructure; the stoves can load up on power slowly over time, then tap into their battery power to deliver the surges needed for high-intensity cooking (a similar dynamic applies to electric-vehicle chargers paired with batteries).

This will mean induction stoves can plug into normal outlets without expensive upgrades to home wiring, said Kennedy, whose Berkeley-based startup Channing Street Copper is developing one such product.

The company advertises ​"plug-and-play installation" for its forthcoming Charlie stove, which begins shipping this spring for Bay Area customers. For $5,999, home cooks get a four-burner electric stove with a convection oven and a 4-kilowatt-hour battery. The product uses lithium iron phosphate chemistry, known for its hardiness and better fire-safety characteristics (and yes, it's insulated so the batteries don't heat up).

Eric Wesoff . 10 February 2023

Canary Media thanks Sense for its support of the Home of the Future series.

Rooftop solar power will play a crucial role in the electrified home of the future. Not every homeowner needs (or is able) to put solar panels on the roof. But for those who can, the ability to generate their own power, when coupled with battery storage, could help ease demand on overtaxed utility grids and render their home more resilient in the face of increasingly extreme weather.

Unfortunately, installing solar is still an expensive and harrowing process. Where should a first-time customer making one of the biggest purchases of their life even begin? For a useful overview, check out Canary Media's handy guide on important questions to consider. Looking for more specific advice? Here are some companies and organizations working to make going solar a bit easier on the customer's brain and bank account.

One way to alleviate the burden of all the decision-making is to enlist the help of an online solar adviser. These entities take on the daunting task of assessing your home's roof, estimating a project cost and finding reputable installers.

There's strength in numbers for solar consumers when they form cooperatives and pool their purchasing power. Solar installers and their suppliers are compelled to compete for business when scores of customers are bundled into a single cooperative bid. This results in cheaper costs for customers and economies of scale for the supplier.

Solar United Neighbors (SUN) brings homeowners together in a cooperative to learn the fundamentals of residential solar and aggregate their buying power. (The nonprofit has even produced a guide to help farmers and rural small-business owners apply for federal grants and loans and make it easier to install solar energy on their land.) SUN-supported co-ops have launched across the U.S., including Arizona, Ohio, Pennsylvania, West Virginia and even Puerto Rico.

The Solarize program also pools solar procurement through local-government-backed programs rolled out in cities including Boston, Houston, Minneapolis and Orlando, with 20 megawatts of co-op installations in New York state alone.

What if you, like the majority of American households, can't install solar because you’re renting, or it costs too much, or your house is in the shade? Community solar allows this pool of citizens (and some organizations) to jointly own or subscribe to a solar project.

Canary's Alison Takemura breaks down the ins and outs of community solar in this helpful explainer and also suggests some good first steps for the community-solar-curious:

While the majority of U.S. states have some form of community solar available, the market is concentrated in Florida, Massachusetts, Minnesota and New York.

As an enticement for developers to build more community solar, the Inflation Reduction Act, which passed in August, offers additional tax credits of up to 20 percent tax credit for community solar installations that benefit low- and moderate-income communities. That's on top of the 30 percent tax credit that's already in place for solar projects.

Although it's mostly affluent homeowners who put solar on their roofs, low- and moderate-income households stand to gain the most from the low-cost energy of rooftop solar because a higher percentage of their income goes to energy costs. These households now make up an increasing share of the solar market, according to a November 2022 report by researchers at the Lawrence Berkeley National Laboratory, and various entities and organizations are working to accelerate this trend.

PosiGen provides solar power and efficiency upgrades for low- to moderate-income households in Connecticut, Louisiana, Mississippi, Pennsylvania, Massachusetts and New Jersey, focusing on customers that most residential solar companies would not consider as potential sales targets.

A number of new initiatives have been launched to lower the energy costs of low- and moderate-income homeowners by installing rooftop solar. Over a dozen states, including Connecticut, Delaware, Hawaii, Illinois, Massachusetts and Rhode Island, have initiated pilots and programs to offer affordable leases, third-party ownership or grants for solar equipment. The economic viability of these programs is often bolstered by new environmental justice tax credit adders included in the Inflation Reduction Act.

The U.S. has some of the world's most expensive home solar due to permitting, labor and tariff-induced module costs — so there's still plenty of cost that can be trimmed and improvements to be made. Dependable, ongoing price drops and efficiency gains mean that solar's inclusion in the home of the future remains compelling.

Residential solar faces challenges ahead in interconnection, net-metering policy and workforce issues, but solar panels are still the shiny object on the decarbonization and electrification stage, despite the siren's song of attention-seeking heat pumps. Both of these energy stars perform best when coupled with improvements in HVAC, appliances, windows, insulation and lighting.

Alison F. Takemura . 10 February 2023

Canary Media thanks Sense for its support of the Home of the Future series.

GOLDEN, Colo. — Snow crunches underfoot as I walk around what was once a humble shipping container. Researchers have now turned its facade into that of a tiny house, complete with two windows and a door. The interior? Unfurnished. With this model home, it's not what's on the inside that counts, but what's on the outside: light beige panels of energy-saving insulation.

On a recent January morn, Chioke Harris, senior research engineer at the U.S. National Renewable Energy Laboratory, shows me these prefabricated foam panels, their faces textured like stucco. They’re made by manufacturer Dryvit from expanded polystyrene — a hard foam that doesn't yield at all under my curious fingers — which can insulate a building like a tea cozy or an ice cooler.

Alison F. Takemura . 6 February 2023

Julian Spector . 7 February 2023

Canary Media thanks Sense for its support of the Home of the Future series.

If you haven't heard of heat pumps, you will soon. Solar panels, batteries and electric cars have been on the scene for years now; heat pumps are the up-and-comer of the clean energy world.

They use electricity to both heat and cool buildings with stunning — some would say magical — efficiency. And they won major federal tax incentives in last year's Inflation Reduction Act that amount to thousands of dollars in savings for each household that installs them.

But heat pumps require a more complex pitch than EVs or solar, with a more varied and obscure economic payoff. And the contractors who actually sell and install home heating often pooh-pooh heat pumps in favor of the fossil-fueled furnaces they’re accustomed to selling.

Canary Media has been tracking the technological evolution of heat pumps and the policies that encourage their adoption, and we’ve compiled that knowledge into this user's guide, geared toward anyone considering the switch to highly efficient electric heating and cooling.

Maria Gallucci . 7 February 2023

Canary Media thanks Sense for its support of the Home of the Future series.

Americans who want to electrify their homes will soon have access to billions of dollars in federal incentives under the High-Efficiency Electric Home Rebate Act (HEEHRA). Low- and moderate-income households specifically will be able to fetch discounts that sharply reduce the cost of replacing polluting gas stoves and furnaces with cleaner electric appliances and heating systems.

The problem is, nobody knows exactly how soon those incentives will be made available. Congress passed HEEHRA last summer as part of the sweeping Inflation Reduction Act. But the U.S. Department of Energy isn't expected to issue guidance on how states should implement the program until later this year. After that, state energy offices will still need to develop their own systems for administering benefits to eligible residents.

Households eager to save up to $8,000 on a new heat pump or shave up to $840 off the cost of an electric stove — two discounts offered under HEEHRA — have plenty they can do to prepare in the meantime.

Canary Media spoke with Jennifer Amann about what steps people can take today to smooth and accelerate the process of applying for and receiving rebates, whenever those are finally on offer. Amann is an expert on residential decarbonization and is a senior fellow in the American Council for an Energy-Efficient Economy's building program in Washington, D.C.

"Now is a great time for people to be planning and thinking about what they might do" to electrify their homes, she said.

The HEEHRA program provides up to $14,000 per household in point-of-purchase rebates for low- and moderate-income families who are looking to replace fossil-fuel-burning equipment such as oil boilers or gas clothes dryers with more efficient electricity-powered units. Rebates are available to both homeowners and renters.

Low-income households are defined as earning less than 80 percent of the median family income in their area. Moderate-income households earn 80 to 150 percent of their area's median income for families. The U.S. Department of Housing and Urban Development has an online tool to help households determine which category they fall into.

HEEHRA's upfront discounts can be paired with federal energy-efficiency and electrification tax credits, some of which became available on January 1. Still, Amman noted that low-income households might not owe enough in taxes to qualify for the credits. And other families might not have the financial flexibility to wait for months until the tax credits appear on their annual tax returns.

Leaky windows, thin wall insulation, inefficient light bulbs and poor ventilation can all increase a home's energy consumption and raise utility bills. Figuring out where a home is losing energy and how to plug those gaps can not only help reduce a family's monthly expenses — it can also enable them to potentially buy smaller appliances when it comes time to access HEEHRA rebates.

"If your home is tight, you may be able to downsize your equipment and get a system that costs less [upfront], costs less to install and less to run," Amann said.

A do-it-yourself assessment is the simplest way to pinpoint a home's weak spots. The Department of Energy provides a thorough guide for inspecting every nook and cranny and, for those who can wield a screwdriver or caulk gun, some tips for quick fixes.

Households should also contact their utilities to see what services (and financial incentives) are available for more professional energy assessments. Many utilities are increasingly offering virtual home audits that allow experts to spot flaws and identify efficiency improvements using FaceTime and other apps. In-person auditors use infrared cameras to measure insulation levels and perform blower door tests to see precisely how much air is entering or escaping from a home.

Major fixes, of course, can also cost a lot of money. Both the Inflation Reduction Act and the Biden administration's $1 trillion infrastructure law include significant new funding for the Department of Energy's existing Weatherization Assistance Program, which helps low-income households to make energy-efficiency upgrades. (Here's how to apply.) The HEEHRA program will also provide discounts for weatherization projects at some point.

A quick survey of a home's appliances can help a family decide which equipment they want or need to replace using HEEHRA rebates, and which appliances they should tackle first.

According to the nonprofit Rewiring America, low- and moderate-income households can expect to see rebates covering 100 percent and 50 percent, respectively, of the following items:

Before residents go out and buy a shiny new induction stove, Amann suggests that they take a look at their electrical panel. Many older homes across the country have a 100-amp panel, which might not be able to handle the additional flow of electricity from new equipment. Most likely, a home will need a 200-amp panel — and it's better to know ahead of time how much time and money such an upgrade will require.

"That's something that can hold up your whole project," she said, noting that families can solicit bids from electricians early on to plan and budget accordingly. A panel upgrade ​"is often the first hurdle you have to get over in going to a fully electrified home."

Besides the HEEHRA rebates for panels and wiring (see above list), the Inflation Reduction Act separately offers tax credits for upgrades triggered by electrification projects.

It's not yet clear whether households that install new electric appliances today will be able to receive HEEHRA rebates retroactively. As such, Amann advises anyone considering ditching their old stoves, boilers and dryers to wait until the discounts are officially available unless there's an urgent need to replace equipment sooner.

While HEEHRA rebates offer significant savings, they likely won't cover every single penny of a home electrification project. Households may still need to spend thousands of dollars, or tens of thousands of dollars, beyond the rebate offerings to install, say, a ducted heat-pump system or a heat-pump water heater.

A growing number of state and local governments have established ​"green banks" and other programs to help low- and moderate-income households and individuals with low credit scores power their homes with clean energy and become more energy-efficient. Connecticut, for instance, offers a low-interest ​"Smart-E Loan" with fixed monthly payments and no money down required. Maryland's Clean Energy Advantage Loan Program offers loans with 0 percent financing for 12 months and reduced interest rates.

"We’re seeing more and more financing tools coming out to support these purchases," Amann said. ​"It's a great idea for people to start thinking about what opportunities may be available that they qualify for."

Such programs are likely to expand under the Inflation Reduction Act, which allocates $27 billion for a new grant program run by the U.S. Environmental Protection Agency. Like the HEEHRA program, the finer details of when and how the money will be made available are still being finalized. But Amann said she expects a significant portion of the funding will go to support state green banks nationwide.

For all the ways that households can prepare, there are still many factors that could delay or complicate the process of electrifying their homes.

To start, the U.S. is facing a major shortage of electricians who can install heat pumps, induction stoves and other clean-energy equipment, as this recent Grist investigation explained. In the story, a duplex owner in Oakland, California described his ordeal in upgrading the electrical panel on his building. He said it took eight months between when the electrician first came by and when the project was finally completed.

Homeowners and renters waiting for HEEHRA rebates will likely need to keep practicing patience (or grinding their teeth) as they seek out contractors to inspect, weatherize and electrify their dwellings.

Navigating the maze of available rebates, tax credits, low-interest loans and other incentives offered by utility, state and federal programs may likewise be a time-consuming and confusing endeavor. Fortunately, organizations like ACEEE are launching new training and technical assistance initiatives to help contractors and community-based organizations to make sense of it all and, ultimately, to help households to ​"stack and braid all these resources" together, Amann said.

"As a nation, we need to make this transition to electrification," she said. ​"And we need to take the extra steps to make sure that those least able to afford this transition are given the support they need to be part of it, as well."

Julian Spector . 8 February 2023

Canary Media thanks Sense for its support of the Home of the Future series.

The home of the future won't just be more efficient and powered by cleaner energy than today's houses. It will interact with the broader energy system in ways that reward the people living there — and that help ensure there's enough electricity for everyone else.

The power grid is already straining to keep up with current demand in the face of extreme weather, like heat waves across the West or winter storms across Texas. To address climate change, the housing sector needs to stop burning fossil fuels and switch to electricity for its energy needs, but doing so could layer a whole new challenge on this already-stressed system.

Simply electrifying all buildings significantly increases the demand for electricity, necessitating even greater buildout of renewables and wires to deliver that clean power. That adds cost and complexity to the clean energy shift when getting any grid infrastructure built is hard enough already. But if these newly electrified buildings are ​"grid-interactive" — that is, equipped with tools to control when they do and don't use energy — then these buildings can lower the cost to keep the lights on and accelerate the adoption of clean energy.

This kind of grid interactivity is already happening, albeit at a relatively small scale: Homes can heat water or cool their interiors when renewable power is cheap and abundant, offsetting demand in the hours when grid power is dirty and expensive. Batteries offer even more flexibility, and smart electric-vehicle chargers can adjust the flow of power into cars based on momentary signals.

"I don't think we should be calling it the ​‘home of the future’; it's the home of the present, because the technology is already here," said Elta Kolo, vice president at Huck Capital, which invests in the sector.

But relatively few households have achieved the full-fledged vision of generating, storing and consuming power based on signals from the grid.

"The state of grid interactivity today is very poor," said Cisco DeVries, CEO of OhmConnect, one of the leading aggregators of grid-interactive home devices. ​"We are nowhere near where we need to be."

Often, people don't stand to clearly benefit from becoming more active citizens of the power network. The grid was designed to deliver electricity to passive consumers, and most regions lack systems for rewarding customers who behave in ways that help the overall system. Even when those incentives exist, folks have to care enough to participate in an obscure energy system that they know little about — or be persuaded to sign up even if they don't.

The urgent question facing the movement for carbon-free homes, then, is how do you convince millions of people to participate in the broader energy system?

The first step is to equip homes with devices that can be controlled digitally. That's exactly what the ​"smart-home" industry has spent years trying to do — selling connected devices based on appeals to comfort, security and energy savings.

Consumers haven't responded as quickly or comprehensively as Silicon Valley evangelists said they would. But after years of industry efforts, smart, controllable devices are finally starting to find their way into millions of American homes.

"Households are increasingly getting smart devices, and people are saying almost universally that the top goal for their smart devices is energy savings," DeVries said.

Smart-home adoption is a crucial stepping stone to unlocking grid-interactive homes. But the latter demand even more from residents. Once a home is outfitted with an array of smart appliances, owners must choose to use them not just for personal comfort and safety, but also to help the broader energy system. Realizing that vision involves surmounting a number of barriers:

Given all those challenges, a robust future of grid-supporting, all-electric homes is by no means guaranteed. Nevertheless, some pioneers are breaking through the logjam of hurdles and signing up thousands of customers to participate in some form of grid interactivity.

These include a broad array of companies: electric utilities, smart-device manufacturers, solar and storage installers, software startups, electric-vehicle charging companies, even automakers themselves. Here's a sampling of those that have made grid-interactive homes the core of their business.

Octopus Energy: Sell cheaper power for more flexible homes

Octopus Energy has its tentacles in a lot of pies. The London-based clean-energy company started out as a retailer that wanted to make its customer-service calls actually helpful and nice. It soon evolved from just selling clean electricity to manufacturing its own heat pumps, installing smart EV chargers, and offering solar and batteries. Last November, ahead of a potential winter energy crunch in the U.K., Octopus enlisted 400,000 of its customers in a flexible demand rewards program, almost overnight.

On its first activation, participating households reduced 108 megawatts of demand during an hour of peak consumption. In the U.S., the company sells retail power in Texas, where it rewards customers with lower electricity rates for each energy device the company gets to control. It's one of the early participants in Texas’ first virtual power plant, which lets households commit their devices to supply the ERCOT wholesale markets.

Sonnen: Turn whole residential communities into power plants

Sonnen has installed 120,000 batteries globally, most of them in Europe, where the company operates them as a decentralized power plant to supply customers with lower-cost electricity. That's not so easy in the U.S., thanks to the patchwork of differing state energy regulations. Sonnen found a way in by working with homebuilders to outfit whole housing developments with batteries. Now it's partnering with solar installers in places such as Utah and California to make more money for customers by helping them interact with the grid at the most valuable times. A whopping 88 percent of sonnen batteries in the U.S. are part of a virtual power plant, said sonnen U.S. CEO Blake Richetta — far higher than the industry norm.

OhmConnect: Gamify energy savings with whatever devices you’ve got

California startup OhmConnect has assembled an army of 300,000 grid-interactive homes worldwide, and those customers don't need to own any fancy clean-energy devices to participate. At its most basic, the company sends a message when the grid needs help, and if a household reduces its consumption during the specified time, OhmConnect pays them for it. Sure, the payments go up if a household has more controllable devices, but OhmConnect gets a lot of mileage out of sending customers smart plugs for major appliances and connecting to their smart thermostats. Incremental progress can add up to meaningful capacity in aggregate, DeVries said. ​"You’ve got to start somewhere that is relatively easy and makes sense to people, and you can build from there." He also tries to make it fun: OhmConnect frames grid interactivity as a game, and customers get rewarded the more they play.

Though these entities vary in terms of the products they offer and the customers they serve, they have arrived at the same core insights on how to successfully market grid interactivity at scale.

One critical lesson: You can't assume regular people want to nerd out on the intricacies of real-time grid operations, however titillating that may be to industry insiders.

"If you ask why…customers [would] want to interact with the grid, the answer is they probably don't," Kolo quipped.

The people selling grid-interactive homes know why it matters (that whole ​"making a clean energy grid actually possible" thing). Their job is to meet customers where they are and find ways to get them to sign up regardless of their degree of interest or literacy in the broader energy system. Three leading strategies for this are: deliver clear financial rewards; automate and simplify the experience; and make the customer part of a bigger story.

Deliver clear financial rewards

It falls to cleantech businesses to distill the complexity of clean-energy supply and demand into simple financial rewards for their customers.

"It ultimately comes down to, what do [the customers] pay?" said Michael Lee, CEO of Octopus Energy U.S. ​"If you can make that cheaper, they’ll come along on the journey with you."

Octopus’ Texas retail business starts by offering a normal electricity supply at standard pricing. But if the customer agrees to let Octopus control smart devices, the monthly per-kilowatt-hour rate drops. Throw in a thermostat, energy storage and programmable hot water heater, and suddenly Octopus customers are paying significantly less for electricity than they would from a conventional retailer. Just allowing the company to control when your electric vehicle charges unlocks a 20 percent discount compared to the norm.

The for-profit company isn't doing this to throw money away. The reduced rates for customers reflect the lower prices Octopus pays to source power at specific times.

"More controllable load means more cheap, off-peak power for us to buy for you," Lee said. ​"The lower the cost we create for our customer, the lower the rates for ourselves."

Notably, it doesn't always work that way. Regulated utilities get to pass on fuel costs to their customers, rendering most of them structurally indifferent to serving consumer demand with pricey gas- or coal-fired units versus cheap solar. And utility regulation typically rewards companies that build new peak power plants with more profit, rather than pressuring them to shift demand out of peak hours.

Sonnen, too, runs a battery-assisted retail electricity business, but it got started in Germany. In the U.S., it's adapted its approach to make grid interactivity a key part of the business model for installing rooftop solar as generous solar policies fall away.

The ​"crown jewel of our U.S. operations," said Richetta, is the Wattsmart program in Utah, a state that phased out net metering to compensate new rooftop solar customers for exporting power to the grid. But by adding a sonnen battery and responding to the needs of the grid, customers can unlock thousands of dollars in rewards from utility Rocky Mountain Power.

"It's true self-reliance," said Zach Randall, VP of sales at ES Solar, which installed nearly 2,000 sonnen battery units for the grid program last year. ​"You don't need to rely on an export rate for solar to make sense."

In California, sonnen has supplied batteries to some 400 homes in partnership with Baker Electric Home Energy. That state is about to slash the compensation it used to give solar customers for exporting power to the grid, a move that many solar installers have said spells doom for the industry. Sonnen takes a different tack: The company says it can insulate customers from any negative impacts of the new net-metering regime by more intelligently responding to price signals in the market and by earning revenue for grid services.

Whether it's lowering the overall price of electricity, paying customers to participate or using grid flexibility to make rooftop solar pencil out economically, these companies offer customers tangible financial rewards for helping the grid.

Automate and simplify the customer experience

The financial compensation detailed above can bring customers in the door. But given the uncertainty around how many people are actually motivated to participate in the broader grid, making that participation as easy and frictionless as possible is a no-regrets strategy.

There are very ​"few wonks like me [who] will download their data and do analysis on it," Huck Capital's Kolo said. ​"This is why automation is important — ​‘set it and forget it’ options with the ability to override [load-reduction events] without penalties."

That last part is significant: If customers are offering up control of their home devices, they need assurance that they can retake the steering wheel if needed. Saving money through smart EV charging sounds great — provided that you always have enough charge when you need to drive.

Kolo also contends that this suite of home energy opportunities ​"needs to exist in one app, one portal, one umbrella brand" to avoid confusing customers with too many unconnected services.

Remember Octopus Energy and the 20 percent discount for letting the company toggle when your EV charges? Octopus also got a license to sell and lease electric vehicles in the state of Texas. That means customers who want an EV can get one, lock in cheaper electric rates and pay their car lease, all on a single bill. It's one way to reduce the friction of adopting a new type of car and registering it for demand flexibility programs (old-school utility Duke Energy is trying a similar concept for its North Carolina customers).

"You have to have automation, plus rate design, plus customer-centricity," Lee said.

Jeff St. John . 8 February 2023

Canary Media thanks Sense for its support of the Home of the Future series.

There's no getting around the fact that the road to electrifying U.S. homes runs through contractors. And it will take a lot more than government incentives or even mandates to get those contractors on board with this transformation that's vital to fighting climate change.

That's the view of longtime contractor, building-science consultant and self-styled ​"house whisperer" Nate Adams. He's the founder of HVAC 2.0, a business that provides software and training for contractors trying to make electric heat pumps a cost-effective option for their customers.

More than 200,000 contractors in the U.S. install heating, ventilation and air-conditioning systems and do other building-renovation jobs like wiring up induction stoves, electric-vehicle chargers, backup generators and solar-charged batteries. They include HVAC contractors, electricians, and a smaller group that focuses on whole-home efficiency audits and retrofits.

Some of the contractors are larger companies, but many are small businesses or sole proprietorships. This is the workforce that needs to ready the U.S. housing stock to run on increasingly low-carbon electricity.

Today, electrification simply doesn't pencil out economically for many of these contractors or the customers they serve, Adams said. The historic level of federal funding that will flow to home electrification through the Inflation Reduction Act and the state-level incentives and mandates encouraging the switch from fossil-fueled to electric equipment may help reduce those barriers, but won't necessarily overcome them, he said. They may even slow progress by adding complexity to the sales process.

That's because equipment costs aren't the main problem for home-electrification retrofits, Adams said. Sure, heat pumps currently come at a price premium compared to fossil-fired furnaces and water heaters, and supply-chain disruptions and bottlenecks have driven up costs. But most of the equipment available is built around mature technologies that have largely proven their efficiency and cost-effectiveness.

The big problem is that contractors make or lose money based largely on how efficiently they deploy their most valuable asset — their workers. Well-trained and qualified electricians, HVAC technicians and other tradespeople are in short supply and high demand today. The more labor hours involved on a job, the higher a contractor's costs and the lower their profit margins, and the less likely a contractor is to propose the job in the first place. And most homeowners do what their contractors suggest rather than demand alternatives.

It's almost always faster and less labor-intensive to replace a broken-down fossil-gas-fueled furnace or water heater with a new fossil-gas-fueled one, rather than design a project around a novel heat-pump replacement. Most homeowners only think about their heating when it breaks down, and are highly motivated to replace it as quickly and cheaply as possible when it does.

Contractors are in the business of giving customers what they want at a price they can afford. Sales pitches based on long-range energy-bill savings are tough when there are considerable upfront costs and complications involved in switching from fossil-fueled to all-electric systems. And trying to use the threat of climate change to convince these contractors to overlook the tough economics may well backfire, Adams warns — particularly in more conservative markets like his home state of West Virginia.

Of the roughly 120,000 HVAC contractors in the U.S., ​"80 percent of them are conservative or centrist," he estimated — and that doesn't take into account their customers’ points of view. ​"If the argument is climate, you’ve shut them down."

We need new business models that can overcome these barriers. Creating and supporting these models will require cooperation between contractors, electric-equipment manufacturers and distributors, and pro-electrification advocates and policymakers. Of the 131 million households in the U.S., about 17 million now use heat pumps. Getting that number up to anything close to the majority of homes over the next decade will take a major shift in how contractors approach the task.

Luckily for the fight against climate change, a growing number of companies are taking on the challenge.

Adams sees the primary task of electrification advocates as helping contractors manage and reduce the ​"soft costs" of electrification. Soft costs include finding new customers, assessing their homes’ needs and educating them on their options, plus filing for permits, paying for inspections, and helping customers navigate unexpected installation snags and long-term performance and maintenance issues. Basically, everything except buying and installing the equipment.

The rooftop solar industry in the U.S. has significantly reduced its soft costs over the past decade. The fledgling home-electrification industry needs to do the same thing. ​"The way we lower prices, to a degree — at least in the space we’re working on — is to create a consistent process," Adams said.

Part of that is decreasing customer ​"callbacks" about faulty or insufficient performance from newly installed equipment, which aren't just expensive but can wreck a contractor's reputation and prospects for new business via word of mouth and online reviews, he said. Conducting better home assessments, picking the right equipment to install, and carefully calibrating it to each home's needs can reduce the kinds of problems that trigger callbacks — even if it may add time and costs to projects that are done right, he noted.

Another part is spreading out soft costs across a larger revenue stream, Adams said. That can be done by increasing the ​"ticket sizes" — the dollar amounts charged for projects. Expanding the overall scope of projects to encompass whole-home energy-efficiency services is one way to increase ticket sizes while also supplying customers with the right equipment and upgrades. Another way to spread out soft costs is to improve ​"closing ratios," or how many jobs a contractor ends up winning out of the total number of jobs they’re bidding for, he said.

And contractors need to know that electrification work will grow steadily for them over time, Adams said, so they feel comfortable hiring and training workers and ordering more electrified equipment.

Smaller contractors don't have much control over how quickly the market for home electrification will grow. That's where companies with a specific focus on large-scale electrification — and with funding to expand — can play an important role in giving contractors a clear path to make a living in this emerging field.

An increasing number of companies see an opportunity to take on the role of electrification matchmaker between contractors and customers.

Take the example of Qmerit, a 2014 spinout of ABM Industries, a company that offers facility-management services nationwide. Qmerit works with electric-vehicle manufacturers and dealers to connect new EV owners to electrical contractors that install EV chargers.

Qmerit's software and services platform pulls together data from automakers, EV-charging manufacturers, customer surveys and building records to smooth the installation process, explained Tom Bowen, president of the company's Qmerit Solutions division.

That process includes assessing whether a home will need new wiring or electrical-panel upgrades to support its new charging demand, a need that can add thousands of dollars and weeks of extra time to a project. About 20 percent of Qmerit's installations trigger a panel upgrade today, but that figure is likely to grow as the market for EVs expands, he said.

To help its contractors do panel upgrades and wiring, Qmerit has partnered with financing providers willing to extend low-cost credit to contractors as well as to their customers, Bowen said. Electrical panels are eligible for the new home-electrification tax credits and grants created by the Inflation Reduction Act, but being able to finance the remainder of the cost can help homeowners decide to move forward with a project.

Once a household has a new panel and updated wiring, it's ready for more electrification. The EV charger is the gateway drug, smoothing the way toward adoption of heat pumps, induction stoves or other electrical appliances.

D.R. Richardson, CEO of Elephant Energy, sees an opportunity to consolidate even more parts of the whole-home electrification process under one roof, making it simpler for contractors as well as for homeowners. The Colorado-based startup launched in 2021 and raised $3.5 million in seed funding in September.

Richardson described the company as a ​"full-stack electrification service provider," offering home-specific system design and installation of heat pumps, heat-pump water heaters, induction stoves and EV chargers.

"We’re fully vertically integrated except for the labor," he said. ​"We partner with a network of vetted contractors to provide them more reliable, regular revenue."

Elephant offers its contractors the use of its software that can remotely audit a home's building envelope and heating load, and pull utility billing data to compare the costs of providing heating from gas furnaces versus heat pumps. Such software systems are usually out of reach for small contracting companies working on their own.

Software has played an important role in fine-tuning energy-efficiency investments and reducing soft costs for residential solar installations. Applying the same concept to improving home-electrification project efficiency can free up HVAC contractors to spend far less time chasing customers or conducting energy assessments and more time on the moneymaking work of installations, Richardson said. It also reduces the risk of installing a system that doesn't provide enough heat — a risk that often leads contractors to pitch oversized heating systems to avoid leaving customers cold and unhappy, he noted.

Elephant Energy uses software to optimize system design and to reduce the total cost of ownership. That includes managing all the applicable rebates that can drive down the upfront cost of heat pumps. In the Colorado territory of utility Xcel Energy, for example, city, county, state and federal incentives can reduce the cost of a heat pump by more than $5,000, he said. But not all heat pumps qualify for the full panoply of available incentives.

Elephant Energy manages equipment purchasing for its contractors, Richardson said, making sure to stock models that are eligible for incentives. The company can take advantage of economies of scale and buy larger quantities of equipment at lower cost, plus it can borrow money at more favorable interest rates. This strategy also provides a store of available equipment in case of supply shortages like those seen over the past few years, he said.

All of this adds up to lower costs for contractors overall — less time spent seeking out and assessing customers, lower equipment costs, and less risk of choosing equipment that doesn't qualify for incentives or doesn't meet customer needs, he said.

"We’re able to offer the customer the same or lower price that they’d get from the typical contractor, while the contractor is spending less than they would have otherwise," he said.

Finally, bundling together lots of separate projects from lots of contractors opens the door to securing more favorable financing terms for a larger scale of business, Richardson said. Elephant Energy now works with the Renu program of the Colorado Clean Energy Fund, a state-run ​"green bank" lender, to finance the projects it lines up between its contractor partners and its customers.

Richardson pointed out that Elephant Energy is also working with Tenet, a Silicon Valley–based startup that offers financing for EVs and home EV chargers, to bring in prospective home-electrification customers. ​"I think we’re on the verge of mass heat-pump adoption," he said. ​"We can partner with companies like Tenet to finance them."

While financing can play a key role in lowering the upfront cost of home electrification, another approach to making new systems affordable is offering equipment leases. That can be a better deal for both homeowners and contractors, says Anuj Khanna, CEO of Service 1st Financial. Khanna's company hopes to scale up a leasing business model across multiple U.S. markets through a network of contractors that's a hundred strong and growing.

The HVAC industry has seen a ​"lot of innovation and progress in terms of technology," with the latest heat pumps offering energy-efficient performance at temperatures well below freezing, Khanna said. ​"Where there's been very little innovation in this industry is in the fundamental business model that contractors use — they go into the home and they sell a box."

Most homeowners are forced to choose how much they’ll pay for that new box when the old one breaks down, he noted. ​"Under a traditional model, they have to pay for 100 percent of that system when they replace it," which disadvantages higher-performance heat pumps that are more expensive but cost less to run over their lifetimes. And while homeowners can finance those replacement systems, ​"once you strike your pen on that contract, it's your obligation" to maintain and repair a heat-pump system.

Service 1st Financial secured $20 million in equity and debt financing in November to expand the network of HVAC manufacturers and contractors using its leasing model, which allows customers to avoid upfront purchasing costs and instead pay a set monthly fee that includes a long-term maintenance contract.

That's a simpler and cheaper option for homeowners, but it's also good for contractors and the distribution companies that sell them equipment, Khanna said. Higher-priced systems are a much easier sell when they’re broken into monthly payments, which opens the door for higher-efficiency heat pumps, which now make up roughly one in three of Service 1st's installations, he said.

Contractors can also lock in 10- to 15-year service contracts that are a key source of ongoing revenue, he noted. And at the end of that contract term, contractors can make a replacement sale — potentially before the system breaks down and forces the homeowner into another emergency replacement situation.

"For a younger homeowner, the leasing option makes a lot of sense," said Dennis Stinson, vice president of sales at Fujitsu General America, a major heat-pump manufacturer that's working with Service 1st. ​"Just like subscribing to cable, it's a fixed payment. And if it ever stops producing heat or cold, there is full coverage" to pay for repairs or replacement.

Some home-electrification providers are going a step beyond guaranteeing heat-pump performance through maintenance contracts; they’re guaranteeing energy savings. Sealed is a New York–based startup that has raised $62.5 million and established a credit facility with New York Green Bank to finance home-weatherization and heat-pump projects. It charges customers monthly payments over 20 years to cover the cost of purchasing and installing equipment, with a fail-safe: If the customers don't see monthly energy-bill savings compared to their pre-retrofit bills, their payment due to Sealed is waived for that month.

This assurance makes customers more comfortable about moving ahead with a heat-pump project — and that means more work for Sealed's contractor partners.

A commitment to energy savings may not be a good fit for every home in every market, Elephant Energy's Richardson said. Sealed works primarily in the U.S. Northeast, where many homes are older and some are still burning heating oil — a fuel that's become much more expensive than electricity or natural gas.

But a similar underlying premise connects companies like Sealed, Service 1st and Elephant Energy, Richardson said. That's to ​"take risk out of the equation for homeowners such that heat pumps are the de facto less risky, less costly, ​‘no-brainer’ idea," he said.

New York City–based BlocPower has taken its own tack on making building electrification work at scale. The startup has more than $100 million in project finance from investors including Goldman Sachs and the Microsoft Climate Innovation Fund, and it is hiring contractors to electrify hundreds of low- and moderate-income homes and apartments, as well as churches and community centers in its home state and in California, Colorado, Illinois and Wisconsin. It also has two ambitious citywide electrification projects in Ithaca, New York and Menlo Park, California.

BlocPower offers equipment sales and installations at low or no upfront cost in exchange for monthly payments over the course of a decade or more. It doesn't promise that its customers will see energy-bill reductions because so many of the factors at play are beyond its control, such as changing energy-usage patterns within buildings or changing utility rates for fossil gas and electricity. But it does promise to cover the cost of keeping customers’ equipment and systems in working order over the life of their contracts.

This kind of risk reduction is particularly important when the homes being electrified are in lower-income and disadvantaged neighborhoods, said Roopak Kandasamy, BlocPower's program lead for its Menlo Park project. Part of that project is targeting the city's Belle Haven neighborhood, a majority Latino and Black community between the San Francisco Bay and the heavily trafficked Highway 101 corridor.

Many of the residents of this historically redlined neighborhood lack the household wealth and credit that could allow them or their contractors to finance home efficiency and electrification on favorable loan terms. To fill that gap, BlocPower and its contractor partners have tapped into a variety of funding sources, including state heat-pump incentives, zero-percent-interest loans from community energy provider Peninsula Clean Energy, rebates from regional energy-efficiency entity BayREN, funding from the Menlo Park city council, a $4.5-million state grant approved in last year's legislative session, and private fundraising, he said.

All of these disparate sources of financing play a role in extending what Kandasamy called the ​"capital stack" for making electrification projects in Belle Haven profitable for contractors. ​"If you’re bringing down the capital aspects significantly — we’re talking about doing a lot of these homes for free — it builds trust for a new technology, and there's work getting done that otherwise wouldn't be getting done, that people wouldn't otherwise be paid for," he said.

That's vital for accelerating residential electrification at the pace needed to fight climate change. The home-electrification industry is ​"about five to eight years behind where solar is now," he said. ​"The typical scaling model for most industries is, we’ll put out a luxury product, and we’ll ride down the cost curve for everyone else."

But with the fight against climate change demanding a massive reduction in carbon emissions across all sectors of the economy by 2030, home electrification can't wait years for wealthy and eco-conscious early adopters to make it mainstream, he said. ​"We don't have time to ride down this curve."

The wide cross-section of work involved in whole-home electrification projects — from energy auditing and efficiency retrofits to HVAC installation and electrical work — presents a challenge to contractors that have typically focused on only one part of this puzzle, but it's also an opening for those that can position themselves to serve homeowners with a complete package, Kandasamy noted.

"It's a broad scope of work; it may be hard to get into," he said, but he thinks sharp contractors will ​"see the opportunity."

They can look to the Bay Area for signs of where the market is headed. There, contractors are ​"booked up" with electrification work, Kandasamy said. ​"They can't train folks fast enough to do all the jobs they’re doing."

Maria Gallucci . 8 February 2023

Canary Media thanks Sense for its support of the Home of the Future series.

Last year, Mary Rivera replaced the gas stove in her New York City home with an electric induction version. Rivera, who has asthma, says she soon noticed feeling less congested whenever she cooked inside her public-housing apartment in the Bronx.

"Now I have no cough," she says in a new video produced by WE ACT for Environmental Justice, a nonprofit group.

The video was released in late January just as America's kitchen appliances were being thrust into the political spotlight — over the past few weeks, Republican lawmakers have been rallying, they say, to save gas stoves from extinction. Their efforts are largely a reaction to recently published research and growing public concern about the health risks that burning fossil gas in kitchens poses to children and adults. (Gas stoves also leak methane, a potent greenhouse gas.)

With its latest pilot study, WE ACT has added to the mounting evidence.

The organization recently monitored the indoor air quality of homes using gas and electric stoves. For the project, Rivera's household and nine others in the same Bronx building were given an induction stove. Ten neighboring households kept their gas stoves to serve as the control group.

After a 10-month monitoring period, households with electric appliances saw a 35 percent drop in daily concentrations of nitrogen dioxide (NO2) compared to those using gas stoves, WE ACT states in its report. NO2 can irritate people's lungs, cause symptoms such as wheezing and coughing, and contribute to the development of respiratory diseases, including asthma.

The households with electric induction stoves also saw significantly lower daily averages of carbon monoxide (CO) — about 43 percent less — than households burning gas to cook. Even at low concentrations, CO can cause fatigue and lead to chest pain in people with heart disease.

In the video, Rivera and other residents of 1471 Watson Avenue share what they learned from the study and why they now prefer cooking with electricity. ​"With my induction stove, it's never having to worry about leaving the gas on, going to sleep with the gas on. It's a lot safer," says another participant, Ayana Kai-Sutton.

WE ACT conducted the pilot program in partnership with New York City Housing Authority (NYCHA), the Association for Energy Efficiency, Columbia University Mailman School of Public Health, and Berkeley Air Monitoring. NYCHA itself is planning to electrify the entire 96-unit housing complex in the Bronx by installing heat pumps and a new electrified water-heating system.

Since the study wrapped, no one who received an induction stove has asked for their old gas unit back, news website The City reported. And residents in the 10 control apartments say they are eager to get induction stoves for themselves.

Stephen Lacey, Julian Spector . 8 February 2023

On The Carbon Copy podcast this week:

Visions for the energy-smart home of the future haven't panned out as expected.

In the mid-2000s, the internet-enabled consumer dashboard was going to be the thing that revolutionized energy in the home. Even Google and Microsoft got in on the action — only to later shut down their energy dashboards when no one was using them.

Then came the smart thermostat, pioneered by Nest. Many hoped the rise of smart thermostats marked the start of a wave of technology adoption that would enable millions of energy-aware homes. They have been helpful for demand-response programs, but the gadget-centric model hasn't yet unlocked a smart-home revolution.

But today, there's a new driving force that is creating more urgency for the grid-interactive home: electrification.

As we electrify the economy and build more variable and intermittent renewables, we need buildings to help balance the grid. And after decades of futuristic visions that never materialized, are we finally at a moment when the smart, grid-interactive home is emerging in a meaningful form?

This week, we dig into that question with Canary Media senior reporter Julian Spector. Read Julian's piece on grid-interactive homes, part of Canary Media's weeklong Home of the Future special series.

Transcript available here.

Maria Gallucci . 9 February 2023

Canary Media thanks Sense for its support of the Home of the Future series.

In East New York, a residential area in the outer reaches of Brooklyn, a 14-story apartment building rises from the site of a demolished water pumping facility. With airtight insulation and advanced ventilation, the new brick-clad complex is designed to use as little energy as possible. Rooftop solar panels and electric appliances limit the need to burn gas for heating and cooking, reducing indoor air pollution and planet-warming emissions.

The 275 apartments at Chestnut Commons are some of the most energy-efficient units in New York City. Just as crucially, the climate-friendly building is reserved for low-income households, in a neighborhood where more than one-third of residents live below the poverty line.

The 300,000-square-foot property is opening its doors at a time when cities across the country are grappling with two pressing challenges: how to provide more affordable housing as rents and home prices skyrocket — and how to decarbonize and electrify millions of homes, offices, schools and other properties. In New York City, home to roughly 8.5 million people, buildings account for nearly three-fourths of the city's total emissions.

Gaurab Basu . 9 February 2023

Canary Media thanks Sense for its support of the Home of the Future series.

On a lazy Sunday morning in October 2018, I grabbed my phone to browse through some news while lying in bed. What I read would change my life. ​"Major climate report describes a strong risk of crisis as early as 2040," the headline blared. The United Nations Intergovernmental Panel on Climate Change had just released its most recent report, and its predictions were dire.

Of course, I had known that climate change was a threat, but I had not understood that we could hit 1.5 degrees Celsius of global warming by as soon as 2030, and how deeply and quickly we needed to cut emissions to save the planet. I walked downstairs to find my pregnant wife and toddler. With hands shaking, I showed my wife the phone and said, ​"This is much worse than I realized." For months, I stayed up late at night after everyone else was asleep learning all I could about the crisis.

Climate change worsens everything I care about as a doctor. It increases health risks from heat waves and natural disasters; it exacerbates the burden of infectious diseases, mental health conditions, food insecurity and water scarcity; and it's caused primarily by the burning of fossil fuels, which results in air pollution, itself a major threat to public health. I knew I needed to act.

So I got to work. As the head of the Cambridge Health Alliance Center for Health Equity Education and Advocacy, I started developing curricula for our courses that highlight climate change's impact on health and how those impacts fall more heavily on low-income communities and communities of color. I also started a climate fellowship that teaches community-organizing skills to health professionals who want to advocate for action on climate. And I became an advocate myself, taking part in both an environmental advisory committee in the Massachusetts governor's office and the city of Cambridge mayor's Climate Crisis Working Group. My goal with these groups has been to bring the health risks of climate change and air pollution to the forefront of the conversation.

The thing about the climate crisis is that once you wake up to it, you see it everywhere. Now with two young kids, my wife and I suddenly saw the sources of greenhouse gasses and air pollutants right in front of us. Nitrogen dioxide is a pollutant released from the combustion of fossil gas, a common fuel that we, like so many others, used for cooking, heating and other household tasks without a second thought. This pollutant is known to harm children's respiratory tract and cognitive development. In fact, a recent study revealed that gas stoves are associated with 12.7% of childhood asthma cases across the United States. According to another major study, Boston-area homes fueled by gas were exposed to 21 hazardous air pollutants, including dangerous carcinogens such as benzene. And most of these emissions occur, yet another study showed, when gas stoves are turned off.