Here’s an uncomfortable truth about home decarbonization: We’re behind schedule, and locking in even more delays every day.
This isn’t because the technology doesn’t exist. And it’s not because it’s too expensive. Roughly every eight seconds, somewhere in the United States, an HVAC contractor installs a one-way air conditioner that the home will rely on for fossil-fueled heating for the next 15 to 20 years. That adds up to somewhere between 4 million and 5 million times per year that homeowners choose equipment that can’t heat with electricity.
Home fuel usage represents 6% of U.S. carbon dioxide emissions, and over 1% of world emissions. But converting all one-way ACs into two-way ACs — also known as heat pumps — in the U.S. can bring down those emissions substantially, and get home heating fuel usage down by 39% at the very least. And, according to research I co-authored in 2021, the whole endeavor would cost roughly $10 billion: comparable to the cost to build a single Meta data center campus in Lebanon, Ohio, or else just a bit more than the 2021 Inflation Reduction Act devoted to rural electric cooperatives.
I’m a rare political conservative in the climate space. I started in the insulation business in 2005 and I’ve been electrifying homes since I pulled my first client gas meter in Cleveland in 2014. Over the past decade, I’ve explored every conceivable path to scale that home decarbonization work. And one major thing I’ve learned: Until we stop selling air conditioners that can only cool, we’re just rearranging deck chairs on the Titanic.
The emergency replacement trap — and a simple fix
Roughly 85% of residential HVAC systems are replaced due to emergency. When your furnace dies at 11 p.m. in January, or your AC quits on the hottest Saturday in July, you’re not researching rebates. You’re not comparing efficiency ratings. You’re calling whoever can come fix it first and you’re taking whatever equipment is on their truck.
This single market reality, which comes up repeatedly at industry conferences, is why downstream programs incentivizing the switch to heat pumps consistently fail, why contractor behavior matters so much, and why supply-side policy is the only path that actually works. If the equipment sitting at the distributor is a one-way AC, that’s what gets installed, even if the homeowner in a non-emergency context would be convinced by either a heat pump-only system or a hybrid (heat pump combined with a furnace).
Any policy encouraging home decarbonization that requires research, rebate applications, or really much consideration at allis designing for planned replacements, meaning just 15% of the total systems installed. It’s ignoring the actual market.
Thankfully, there is a solution, one that is both simpler and cheaper than almost anything else in the climate toolbox, at least in North America: convert every one-way AC into a two-way AC — which is what the industry calls a heat pump — at the point of manufacture or distribution.
The difference between an air conditioner and a heat pump is embarrassingly small. It’s primarily a reversing valve plus a few supporting components, totaling between $100 and $200 in manufacturing costs according to a 2016 Department of Energy study; when it comes to the costs that customers (and distributors) actually see, the cost difference is typically between $300 and $800. Today, I can buy the reversing valve alone for about $100 at a supply house. Entire mini split heat pumps sell on Temu for $400, including delivery.
Compare it to two nearly identical cars — one with reverse gear, one without. The one without reverse costs almost as much but can only go forward. No one would even consider buying it. But one-way ACs are an example of precisely this intellectual absurdity: You pay nearly the same price to get half the functionality.
Every major manufacturer already makes both versions. The installation process is nearly identical. The supply chain is already there. This doesn’t even require huge ambition; it’s a matter of swapping parts.
It’s important to note that retrofitting an existing air conditioner into a heat pump is impractical. Refrigerant changes and invasive parts modifications make it labor-intensive, expensive, and failure-prone. Heat pumps need to be built for purpose at the factory, not converted in the field.
Making the economics work
Switching an AC to a heat pump translates to a reduction in carbon emissions of between one and three tons per year, over a decade or even two. The specifics vary heavily based on climate zone, insulation levels, and generation mix.
The costs are negligible: between $7 and $60 per ton of carbon reduction, if the right federal or state-level incentives are in place for upgrading an air conditioner to a heat pump of the same model at the manufacturer or wholesale level. That makes switching out ACs one of the cheapest climate interventions available anywhere. Few solutions come in below $100 per ton; direct air capture runs between $500 and $1,000 per ton.
Two-way ACs are also inclusive. With incentive programs that cover the cost difference between AC costs and a heat pump, even low-income families with central air conditioning can obtain a heat pump — and therefore the ability to both heat and cool their home, without having to pay for expensive heating fuels like propane or oil — for little to no extra cost over what they already pay for cooling alone.
CLASP’s Hybrid Heat Homes paper modeled between $70 billion and $100 billion per year in improved air quality benefits from switching from one-way ACs to heat pumps — or a 700% to 1,000% ROI on program costs. This is a fiscally conservative idea that should be conservative-friendly, but so far it has largely been blue states that have pushed heat pump adoption.
There’s no time to waste. HVAC equipment has a useful life of 10 to 20 years. We still have a viable path to getting at least 95% of U.S. homes capable of electric heating by 2050 — but it’s rapidly narrowing. To get there, we need to be installing virtually 100% heat pumps by the early 2030s.
(It’s worth noting that many heat pumps will be paired with furnaces, at least at first, and that’s okay. Most homeowners and contractors aren’t ready for full electrification; we need to spend about a decade with hybrid HVAC in cold climates to get the market used to heat pumps.)
The arithmetic is simple: A heat pump installed in 2025 will likely run until at least 2040 or 2045, at which point we’ll be closing in on mid-century. Every one-way AC installed today is a decision to punt decarbonization to 2040 or beyond.
The U.S. market sells around 10 million to 12 million residential HVAC units installed per year. The good news: Heat pump sales are growing — and quite quickly in 2025, in fact.
The less-good news: The project of home decarbonization doesn’t yet have a clear end date, a day where all new homes will come with a heat pump and all existing homes have replaced their one-way AC with a two-way system. Climate progress depends on it, as do potential cost savings for U.S. families that are currently in an affordability crisis.
But as long as we’re still selling millions of one-way ACs annually, we’re filling the bathtub while the drain is wide open.
Existing momentum
Even as there are certain intractable complications — the emergency replacement trap, most significantly — the North American market also has certain strokes of luck.
The U.S. and Canada have a structural advantage almost no other market does: ubiquitous ducted furnace-and-AC systems. In most of the world, electrifying heat means replacing entire boiler-based systems with air-to-water heat pumps — hence the $10,000-plus incentives common in the EU and U.K. that will likely prove unsustainable.
Stateside, however, we can transform a heating system by swapping a few hundred dollars in parts during routine AC replacement. Good, fast, and cheap.
This is already working. In 2023, Vancouver, Canada required two-way ACs at equipment replacement and for new builds. The implementation has been remarkably smooth. Distributors welcomed the change because it simplified inventory: fewer product lines to stock, more warehouse space. And contractors adapted quickly.
Vancouver changed what’s on the shelf, and the problem solved itself. That’s the model in action.
If we’re serious about finishing home decarbonization — not just starting it, but actually finishing it— we need to answer one question: When do we stop selling equipment that can’t heat with electricity?
Without an answer, we have no end date. Converting ACs to heat pumps doesn’t guarantee completion, but if we don’t explicitly encourage it, the odds are essentially zero. The technology exists. The economics work. The supply chain is ready.
Next: Why our current playbook — rebates, mandates, and climate messaging — is keeping us stuck. And what the evidence says actually works.
Nate Adams, also known as “the House Whisperer,” removed his first client gas meter in 2014 and in the years since has taught numerous HVAC contractors how to do the same. He is a longtime electrification advocate, and on the advisory board for ACHR News. He and his wife Rachel create electrified immersive vacation rentals near the New River Gorge National Park, and own 11 heat pumps personally. The opinions represented in this contributed article are solely those of the author, and do not reflect the views of Latitude Media or any of its staff.
