Why Are There No Heat Pump Stoves?

A heat pump does not make heat, it carries heat from a cooler place to a warmer one, and the wider that temperature gap gets, the less it delivers for each unit of electricity. Warming a house is a small gap, so a good heat pump returns three to four units of heat per unit of electricity, but searing a steak is a gap about seven times wider, and the return falls to roughly one, which is what a plain electric coil already gives you far more cheaply. No working fluid used in heat pumps even stays usable at frying temperatures, so a heat pump stove would cost more, cook slower, and save nothing.

Open your fridge. That gentle hum you have ignored your whole life is a heat pump, and it is very good at its job.

Walk around the house and you will find more. Heat pumps now warm rooms, heat water, and dry clothes. ENERGY STAR certifies heat pump clothes dryers that use around 70% less energy than a conventional dryer.

Then you reach the stove, and the streak ends. Every hob on the market either burns gas or pushes electricity through something until it glows. Nobody sells a heat pump stove.

This is not because engineers forgot. Cooking asks a heat pump to do the one thing it is worst at.

Your Kitchen Is Already Full Of Heat Pumps

Your refrigerator does not make cold. It picks up heat from inside the cabinet and dumps it out the back. That is why the coils behind it are warm.

An air conditioner does the same trick pointed outdoors. Reverse it in winter and it heats your home. That is all a domestic heat pump is. The compressor and coils do not care which way you face them. It is also why putting hot food in the fridge makes the motor work harder.

So your kitchen already runs a heat pump all day. The stove is the odd one out, sitting there burning things.

What Does A Heat Pump Actually Do?

Rub your hands together. You just made heat out of movement, from scratch. That is what a gas flame and an electric coil do. They create heat.

A heat pump does something stranger. It creates no heat at all. It fetches heat that already exists somewhere else and carries it to where you want it.

Here is the part that trips people up. Cold air still contains heat. Air at 0 °C (32 °F) sits a long way above the true bottom of the temperature scale, so it is loaded with heat energy. A heat pump reaches in, grabs some, and hauls it indoors.

The hauling is done by a liquid called the working fluid (you may know it as refrigerant). It soaks up heat in a cold coil outside and boils into a gas. A compressor squeezes that gas and makes it hot. The gas gives up its heat in a hot coil indoors and turns back into a liquid. Round it goes again.

That word "carries" is the whole article. A heat pump is a delivery service, not a factory. Its cost depends on how far uphill it has to carry the parcel. Hold on to that.

We measure the result with COP, short for coefficient of performance. For every unit of electricity you feed in, how many units of heat come out? HyperPhysics at Georgia State University puts typical commercial heat pumps at between three and four.

A COP of 3 sounds like it breaks physics. It does not, and the first law of thermodynamics survives intact. Two of those three units were already outside in the cold air. The electricity only paid for the carrying.

Why Does My House Feel Cold With A Heat Pump?

This is the most common complaint from new heat pump owners. The answer is a preview of everything that follows.

A gas furnace blasts out air that is properly hot. A heat pump does not. NYSERDA puts it plainly: unlike furnaces, heat pumps put out slow, steady heat. Stand at a vent and the air can feel lukewarm, even while the room warms perfectly well.

That is not a fault. It is the design working as intended. A heat pump delivers heat at the lowest temperature that will still warm your house. Ask it for hotter air and its COP starts falling.

So the machine trades delivery temperature for efficiency, on purpose. Which raises the obvious question. How much does it lose if you push that temperature up?

What Is The Biggest Disadvantage Of A Heat Pump?

The honest answer is not cost, noise, or lifespan. It is lift: the temperature gap between where the heat pump picks heat up and where it drops it off.

COP is not a rating stamped on the machine at the factory. It is a property of the gap. Change the gap and the same hardware gives you a completely different number.

You may already know half of this story. It is why heating a home costs more than cooling one, and why a heat pump struggles as the outdoor air gets colder. That is the gap widening from the bottom. What follows is the same equation attacked from the top, and the top is far more brutal.

There is a hard ceiling on how good any heat pump can be. It depends only on those two temperatures:

COP ceiling = T_hot ÷ (T_hot − T_cold)

T_hot is the temperature you deliver heat at. T_cold is where you collect it from. Both must be in kelvin, which is Celsius shifted so zero sits at the coldest temperature possible, −273.15 °C. Add 273.15 and you are done. Use Celsius instead and the arithmetic produces nonsense, including a cheerful divide-by-zero on a freezing day.

Let us run a house. The heat pump delivers 35 °C (95 °F) air, and it is 0 °C (32 °F) outside.

1. Convert: T_hot = 35 + 273.15 = 308.15 K, and T_cold = 0 + 273.15 = 273.15 K
2. The gap: 308.15 − 273.15 = 35 K
3. The ceiling: 308.15 ÷ 35 = 8.8

Real hardware never reaches its ceiling. Measured industrial systems hit about 61% of it, and ordinary equipment sits lower. Call the band 40% to 60%. That puts our house somewhere between 3.5 and 5, a little above the three-to-four figure usually quoted for domestic units.

Field data agrees. The Cold Climate Heat Pump Challenge, reported by PNNL, found median heating COPs of 1.6 to 5.2 across real homes. Even in the punishing −18 to −15 °C (0 to 5 °F) bin, the median was 1.9.

Now notice what the equation says. The gap sits on the bottom of the fraction. Make the gap bigger and the whole thing shrinks. No compressor can argue with that.

What Happens When You Point A Heat Pump At A Frying Pan?

Searing a steak needs a pan surface up around 235 °C (455 °F). The heat pump, meanwhile, stands in a 20 °C (68 °F) kitchen. To pull heat out of a 20 °C room, its cold coil has to sit below the room, at roughly 5 °C (41 °F).

Same equation. New numbers.

1. Convert: T_hot = 235 + 273.15 = 508.15 K, and T_cold = 5 + 273.15 = 278.15 K
2. The gap: 508.15 − 278.15 = 230 K
3. The ceiling: 508.15 ÷ 230 = 2.2

The ceiling has fallen from 8.8 to 2.2. Apply the same 40% to 61% reality check. A real machine delivers somewhere between 0.9 and 1.3.

Sit with that. A plain electric coil has a COP of exactly 1. One unit of electricity, one unit of heat, every time, no moving parts, about twelve dollars.

So the heat pump advantage does not shrink at cooking temperatures. It lands on top of the resistance coil and stops being an advantage. You would buy a compressor, two heat exchangers, a charge of working fluid and a lifetime of servicing, in exchange for roughly nothing.

Even browning is a stretch. A 2025 review of the Maillard reaction puts the browning that makes food taste good above about 120 °C, and really going well beyond that. Deliver 160 °C (320 °F) and the ceiling is 2.8, so a real machine manages roughly 1.1 to 1.7. Better than a coil, technically. Not enough to justify a compressor in your countertop.

Why Can't Refrigerants Get Hot Enough To Cook?

Suppose you did not care about efficiency and just wanted the thing to work. You still could not build it. There is a second, separate wall.

A heat pump delivers its heat when the hot working fluid condenses back into a liquid. That change of state is where the energy comes out. But every fluid has a critical temperature, a point above which it refuses to be a liquid no matter how hard you squeeze it. Above that point there is no condensing, and the delivery mechanism is simply gone.

Those temperatures are not high. The IEA's Annex 58 report on high-temperature heat pumps tabulates the candidates. R-1233zd(E) gives up at 166.5 °C. R-1336mzz(Z) manages 171.3 °C. Ammonia quits at 132.3 °C, and carbon dioxide at a frankly unhelpful 31.0 °C.

You cannot even use the last stretch. The same report advises condensing about 15 K below the critical point for efficient operation. Take that margin off and the best mainstream fluids top out near 156 °C (313 °F). That is below good browning, and nowhere near a sear.

The obvious escapes are closed. Water has a gloriously high critical temperature of 373.9 °C, but Annex 58 explains why it does not rescue you. At kitchen temperatures, water vapor is so thin that the required swept volume and pressure ratio become very high. You would need a compressor the size of the kitchen.

Industry Has 200 °C Heat Pumps, So Why Not A Heat Pump Stove?

Here it gets genuinely counterintuitive. Industrial heat pumps do reach cooking temperatures, at a respectable COP.

The IEA's Heat Pumping Technologies programme reported two large projects in 2025. One raises steam to 144 °C and measured a COP of 2.3. The other delivers steam at 195 °C (383 °F), hot enough to sear anything you like, and also measured 2.3.

So the hardware exists. Why can it not go under your hob?

Look at where those machines start. The first draws from a 33 °C source. The second draws from 65 to 70 °C hot water, waste heat the factory was throwing away anyway. Run the numbers on the second one:

1. Convert: T_hot = 468.15 K, and T_cold = 343.15 K
2. The gap: 125 K, not the 230 K your kitchen imposes
3. The ceiling: 468.15 ÷ 125 = 3.75, and 61% of that is 2.29

The measured figure was 2.3. The report states that project reached 61% of its theoretical ceiling. Apply the same 61% to the other project and you get 2.29 as well. Two unrelated installations, same answer, matching the physics on the first try.

That is the punchline. Those machines are not winning on clever engineering. They are winning because a factory hands them free heat at 70 °C (158 °F), so they have half as far to climb. Your kitchen has no waste heat stream. A stove starts at room temperature every single time, and that extra 105 K of climbing beats any compressor anyone could design.

The same report notes that lifts beyond 80 K are already where industrial heat pumps begin to struggle. Cooking asks for nearly three times that.

Would A Heat Pump Stove Even Cook Fast Enough?

Set the thermodynamics aside. The practical objections are almost as damning.

Cooking is a high-power, fast-response job. You want serious heat in the pan within seconds, and it gone just as fast when the sauce threatens to split. A compressor and two heat exchangers cannot do fast. There is thermal mass, a working fluid that has to circulate, and a compressor that hates being slammed between settings.

Then there is the side effect nobody would tolerate. A heat pump stove pulls its heat out of the room it stands in. Cook a Sunday roast and you would be air conditioning your own kitchen at the same time. Useful in Brisbane in January. An act of hostility in Manitoba.

So: no energy saving, far higher cost, slower response, more maintenance, and it chills the room. There is no product on the market because there is no case for one.

What Should You Cook On Instead?

The honest answer is induction, and not because it beats 100%.

An induction hob has a COP of essentially 1, exactly like a resistance coil. It cannot do better. What it does instead is stop wasting the heat it makes. It generates that heat inside the pan rather than under it.

That matters more than it sounds. ENERGY STAR notes that with gas cooking, only around 33% of the heat reaches your food. The rest heats your kitchen. The US Department of Energy reports that induction is up to three times more efficient than gas, and up to 10% more efficient than a conventional smooth-top electric range.

So the win at the stove was never going to come from a bigger multiplier. It came from aiming the heat properly. Once COP 1 is the ceiling, "heat the pan, not the room" is the only lever left. Induction pulls it hard.

So, Why Are There No Heat Pump Stoves?

Because a heat pump's advantage was never a property of the machine. It was always a property of the gap.

That is the mental switch worth taking away. Most of us think of a heat pump as an efficient device, the way an LED bulb is an efficient bulb. It is not. Its efficiency is set by the job you hand it. Give it an easy climb and it looks miraculous. Give it a hard one and it becomes an expensive kettle.

Heat pumps conquered the rest of your home because those jobs are all short climbs. A fridge at 4 °C. A room at 21 °C. Clothes at 50 °C. Water at 60 °C. Every one is a gentle slope, and on a gentle slope the physics pays you three or four times over. Cooking demands a climb of more than 200 K. The same equation that makes heat pumps brilliant at the easy jobs makes them pointless at this one.

So the next time you sear a steak and the pan roars, look around. This is the one corner of your house where the second law refuses to give you a discount. Everywhere else, it is quietly handing you three units of heat for the price of one.