Of course heat pumps emitting no particulates and being able to run on renewables are also good reasons, especially as the health impact of living in cities with high PM2.5 values becomes clearer. But I don't think those are the primary drivers.
Many models are in very high demand. Some of the units I looked at recently were back ordered so far that I was told to pick something else if I expected to have it within the year.
The demand is very high because the technology is good. It’s not a campaign or conspiracy.
There are lots of different groups looking to push heat pumps for the above reasons. Governments are concerned about both war and global warming. Ukraine supporters are concerned about Russia getting more money (to wage more war). Green activists are concerned about global warming. All have their own reasons to push heat pumps on everyone.
Rather, it's a combination wanting to get to net zero, so no emissions, with the big problem of generating enough green electricity. A heat pump system has no emissions and consumes much less electricity that an electric boiler/electric heater.
There are government subsidies but it's still much more expensive in the end. I think they are simply too expensive and impractical to install for most people.
BTW my town has an all-electric mandate for new construction already, and there's a lot of that. There's also a bylaw that takes effect in 2025/2026 banning gas-powered landscaping equipment.
OTOH, a few months ago my stepmother installed minisplits after getting quoted $22K to install a whole-home forced air heat pump (going from no forced air at all, so part of that cost was ducting, though it's a single story ranch house so not terribly difficult).
Somewhere between those two points, prices went insane.
I imagine the "proper" heat pump costs a lot because it has to integrate into your central heating - heat and pump water etc. But I also imagine for a lot of people in this country 2-3 mini splits like this one would be absolutely sufficient, wouldn't cost a fortune, and would save them money(plus they can be used for cooling when needed).
In the US where AC is common, summer is generally peak electricity usage. I suspect this will become true in Europe as well with the heatwaves becoming a regular occurrence.
I'd love to see a source on that. There is very little technological difference between an air conditioner and a heat pump aside from refrigerant reversing valves that allow changing which end is the condenser and which the evaporator.
If you poll the current installed base for HVAC, I suspect you'd find that the (vast) majority of systems are minimum SEER rated (i.e., least efficient) systems, so SEER 13/14 (just became SEER 14 this year).
In comparison, if you're already paying the premium for the heat pump system, likely you also pay an additional premium for a higher SEER unit. Also, what I've seen when doing some online shopping that most heat pump systems marketed seem to be higher SEER. Likely, because the cost associated with additional heat pump stuff drives into a higher end market where you 'might as well' make them higher SEER as well (with inverter compressors, variable fan speeds, etc).
Thus Japan acting as a breeding ground for cheaper, replaceable, mini splits. The American manufacturers sold into the HVAC specialist market which was efficiency insensitive but cost sensitive. Thus a bi-partite market.
The only reason mini splits have not bankrupted the American manufacturers yet is many Americans still rely on expensive HVAC specialist to do installs. Thus mini splits extreme cost advantage is buried by expensive installs.
Condensation is - air conditioners have an integrated drip tray which drains to the outside, but if you ran chilled water through radiators they'd all make puddles of condensation on the floor. Retrofitting drains might be possible but I've never seen one and I can't imagine it'd be cost-effective vs installing mini-splits.
The house also has an exhaust fan on a timer, paired with small vents on several windows around the house, to cycle in fresh outside air. But practically for much of the year we just open the windows for fresh air since we live in the temperate PNW climate, wildfires aside :(
I looked in to installing a minisplit heat pump system last year, but the quotes I got were outrageous ($25k+) plus as a retrofit it's not the most elegant integration. Someday I'd like to do the conversion and ultimately decommission the gas boiler, but at that price tag it's not happening soon.
In the short term I bought one window AC and one portable AC for a combined ~$1000. It's not ideal but we only have a few weeks a year where cooling is really needed, and a few more where it's a nice luxury but not a necessity.
I haven't checked the electricity usage but I can't imagine it is much. The system is literally just a small fan and a solenoid valve. Maybe your parents opted for a steam system, whereas mine is called a flow through style.
And, since the heating season is there only time you need humidifying on this context, all the "waste" heat is just heating your home.
Economic but also legal and geopolitical: fuel oil furnaces are getting restricted or banned, and the combination of climate change, air quality standards, and russian instability makes gas look at lot worse than it did 10 or 20 years back.
But seriously i think it’s just that awareness hit a critical threshold so the hysteresis kicks in and articles proliferate. In both cases.
Heat pumps are also inexpensive on initial cost and less expensive than straight AC with gas heat.
They are also low maintenance in comparison to straight AC with gas heat.
Very popular units in southern US.
I priced out a heat pump versus just an AC and gas furnace in my area, and it was a similar spread a few years ago for me in Texas.
And yet what I see time and again is that initial purchase price is the only focus for construction costs, even rehab work. Those budgets are a separate bucket from utility bills so lower priced projects get approval even if utility bills will be higher.
Couple "fun" things about a heat pump; You will smell burning the first time the electric strips are used every year moving into the heating season, it's just dust burning off. Once you start moving into colder weather you might notice the system changing into defrost mode so it can melt ice off of the outside coils. There's a variety of sounds that accompany this and you might even see a bunch of steam coming off of the outside unit. It isn't smoke and it's normal. Every year there's a flood of 911 calls about this.
Anyone doing the math today on a similar purchase should really check out how much they can get from the government: https://www.rewiringamerica.org/app/ira-calculator
This is, of course, the regulation as it stands today; things can always change. Additionally NYC alone likely doesn't account for the attention. But, other metros and municipalities could have similar legislation.
I’m sure there’s others in my position.
The first is your conventional type system, this is usually what AC units are in the US. They run at maybe 1 or 2 speeds. These type of heat pumps are common in the southern parts of the US but also will be found paired with a gas furnace in the northern US. Since they don't adjust their output dynamically they tend to start losing capacity/efficiency significantly around 25-30F.
The second is an inverter driven heat pump. You usually find these in mini splits but they can also be found in a standard air handler form factor that would replace a furnace. The inverter allows the compressor to adjust based on demand and exterior temperature to maximize efficiency. This allow these units to operate efficiently down to -13F depending on the unit. Now there will still be some capacity loss at those temps so during the design of the system this has to be taken into account.
For detailed information on the efficiency of heat pumps I would check out NEEPs website. It is a great resource, it will show you capacity and efficiency (COP) of tons of different units across their operating temperatures.
I don't know what the coefficient of performance is at that temperature though.
Heat pumps require different system design than a traditional setup, where the cooling load is usually the driving force. You might need a bigger heat pump to handle the heating load in very cold weather accounting for the efficiency loss.
Don't you want to resist to turn to explanations like this, that require some invisible force to pull the strings? I think there are more realistic ways to imagine this happening.
If for example a pop star is getting a lot of attention, in multiple countries, what is the mechanism behind that? And is it orchestrated?
I have heat pumps through a mini split system. I like them so much I’m redoing my entire HVAC to add ducts with heat pump powered heating and AC. They’re kind of a miracle: they produce great heat (way better than a gas-powered furnace), they’re ultra-efficient, and they’re whisper quiet.
I don't really know how trends and fashions form and haven't thought so much about it. Some aspect of it might look like research into the ising model and phase transitions - small changes in "temperature" everywhere in the mass of people might look like a phase transition in the overall mood.
If the roof of your house produces enough electricity for the people living it and the heating (and cooling) of all rooms, it is a no brainer to switch to a form of heating that relies on electricity.
For consumers it's also became clear that being slightly more independent from centralized heating and/or energy infrastructure is a good thing
There was also push to do the opppsite to neutralise that threat to fossil profits e.g. Bjorn Lomberg the skeptic saying that we didnt have any tech that could replace gas, so the only response to Crimea was to frack or invent totally new tech, not rolling out renewables and heat pumps faster.
"Fracking Could Free Europe from Putin"
https://www.forbes.com/sites/bjornlomborg/2014/06/23/frackin...
> Still, many EU politicians talk mostly about expanding renewable energies as a way of making Europe independent of Russian energy. Connie Hedegaard, the European Commissioner for Climate Action, said the Ukraine crisis should be a “wake-up call” for European countries to make the switch from Russian gas to clean, renewable sources of energy.
> But this simply ignores reality. According to the International Energy Agency (IEA), Europe gets just 1.3 percent of its energy from renewables like solar and wind, whereas it gets about 75 percent from fossil fuels and most of the remainder from nuclear. Even an extremely optimistic scenario from the IEA suggests that by 2035, Europe will only be able to generate 8 percent of its energy from these renewables. Focusing on them is simply populism without realism.
At that point, climate skepticism was strong enough politically to prevail. They tried to use this latest annexation to promote fracking etc. too but it seems to have largely failed.
I mean, yes. They're much more energy efficient than the alternatives and will play a key part of removing our dependence on fossil fuels.
> I understand that its for climate benefits but it feels very coordinated.
That seems like a good thing?
Cost is going to vary greatly on the electricity and gas prices in your area, so it's hard to give a definitive answer there.
With regards to energy efficiency, my understanding is that heat pumps can be up to 400% (300% typical), which is naively much better than gas which is at most 90% efficient (70-80% typical). This doesn't take into account the extra innefficiency of generating the electricity in the first place, but a quick google tells me coal plants are typically 33% efficient, with combined cycle gas plants being typically being 50% efficient. Even at those levels, heat pumps still look to be coming out ahead to me. And that's not even taking into the possibility of green energy generation through renewables or nuclear.
Most of the energy is coming from the ambient air, only a small amount of electricity is used to change what temperature that energy is available at.
[1] A very simple mental model you can use to understand the difference between temperature and energy for a gas is that temperature is the number of times the gas molecules bump into each other in a second, while energy is how fast the gas molecules are moving. So if you have a very low pressure gas, even all of those molecules have a ton of energy in the form of motion, the temperature of the gas will be quite low because the gas molecules won't interact often. But compress that gas down to a small volume, and the molecules will bump into each other all the time even though they don't have much more energy.
The core idea is that you aren’t using 1 unit of electrical energy to create 1 new unit of heat energy. You are using 1 unit of electrical energy to capture several units of pre-existing heat energy from the environment and pump it indoors.
Burning 1 joule of gas would give you 1 joule of heat in a perfect world. That is what a non pump does.
https://en.wikipedia.org/wiki/Combined_cycle_power_plant
> (CCGT) plant[s] achieve a best-of-class [...] thermal efficiency of around 64% in base-load operation. In contrast, a single cycle steam power plant is limited to efficiencies from 35 to 42%
This is a huge problem in Europe where a house is expected to last a 100 years, in many areas much more.
An expensive high efficiency gas furnace might be 95% efficient (most normal furnaces are in the 80's)
1000 x 0.95 = 950 BTU/cuft
A high efficiency natural gas power plant is 60% efficient and a modern high efficiency low temp heat pump can have a COP up to around 2.7 at 17F
1000 x 0.6 x 2.7 = 1620 BTU/cuft
A 40% power pant is still more efficient than a 95% furnace with a 2.7 COP heat pump.
There is obviously more to this, there are some grid losses to account for but has to be compared to piping losses, there is also cost factors and also how much renewable is mixed into your grid supply, but generally once that heat pump is above around 2.5 COP it starts to make sense, this is a no brainer in milder climates which is why I have a heat pump and no gas furnace here in FL even though I have gas to the house for other uses.
They're a no-brainer in every climate. Newer heat pumps can handle fairly cold temperatures (-13°F) pretty easily, there may be a loss in efficiency but in the majority of the world it doesn't stay that cold. A few days of lower than normal efficiency, and at worst plugging in a few space heaters if it gets extremely cold for a day or two, does not change the overall math of heat pumps being a better solution.
Hell, that's just me talking about air source heat pumps. No reason for new construction to not use ground source and get better efficiency and not worry about ambient outdoor temperatures.
I am looking for genuine research, and not from paid mouth pieces.
Majority of the comments here seem like agents of heat pump industry. And HN rules forbid me from calling them that.
Heat pumps do not create heat, the refrigeration cycle moves heat from point A to point B. For every KWh of electricity used by your refrigerator, air conditioner, or heat pump, 3-4 KWh of heat energy can be moved where you want it to go.
Even if you have a (comparatively) inefficient combined cycle natural gas power plant that is 50-60% efficient, you're still getting 150-200% efficiency for heating with a heat pump compared to 80-95% for a natural gas furnace.
I live in Boise so we have pretty cheap utilities compared to the national average, but here's some math:
1 therm (~30KWh of energy) is ~$0.72 from Intermountain Gas, the furnace in my rental is 90% efficient, so I actually get 27KWh of heat from every therm I burn.
Idaho power has a tiered tariff for residential customers, with a peak charge of ~$0.098 per KWh during the winter for usage over 2,000 KWh in a month.
Every therm my gas furnace burns costs me as much as ~7.5KWh from the electric utility, but those 7.5KWh can provide me with 30KWh of heat with a quality heat pump, which would require a 100% efficient natural gas furnace to reach. Add in that gas furnaces have a much higher TCO because of maintenance and repair compared to a heat pump, and they're not just energy inefficient in comparison but even just plain more expensive to operate even with incredibly cheap fossil fuels.
Gas is burned creating a certain amount of heat, in a furnace some is lost to exhaust the rest goes into your house. That is the furnace efficiency.
When gas is burned at a power plant the same number of BTU is released, but it is used instead in a heat engine to create mechanical power which is then turned into electrical power, the rest is lost to exhaust, this is the power plant efficiency.
Heat pumps are over 100% efficient because they capture heat from the environment around your house which is warmed by the sun. So even though more energy is lost in creating electricity than burning directly in your house, this is more than made up for by using the ambient heat around your house, it is essentially solar assisted (in the case of air source).
I am happy you have an open mind, but the fact that you are trying to tear the technology down when you apparently have no idea how it works or what it even is- hopefully you realize that it is also used for air conditioning, and is essentially just an air conditioner running in reverse... I hope this is a learning experience for you.
At the very least it gives me hope that those trying to tear down this technology are just ignorant, I had real suspicions that they were agents of the fossil fuel industry, or this was something Fox News and the like decided to target and is now being parroted.
That isn't to say they cannot work I personally have a heat pump in my house and it worked fine through the -15F weather we got. But it requires careful design work initially. Also you run into simply size constraints where residential heat pumps tend to max out at 5 tons (60k BTUs) typically when furnaces can easily get up into the 100k+ BTUs. Which might require multiple heat pumps and separating existing duct work. But definitely new construction should start designing around these constraints now.
Ductless mini-splits remain an option as well. I'd actually like to see somebody make some ground-source exchanger that ductless heads could connect to, because they're much cheaper to install than a multi-zone ducted system.
In extreme climates, gas burning is cheaper. And quite clean. There are some objections because of delivery leaks, but that is a separate concern.
Switching everyone to heat pumps would lower emissions from heating and cooling in the US by 160m tonnes a year [1], which is something like 30-40%.
It's true that upfront costs of heat pumps can be higher, but thanks to the IRA there are huge subsidies available (and further subsidies in many states) which make up most or even all of that difference. The lifetime costs of heat pumps with these subsidies should be substantially lower than high efficiency natural gas furnaces.
[1] https://www.rewiringamerica.org/circuit-breakers-heat-pumps
(Those subsidies, by the way, are one of the reasons "everybody is talking about heat pumps")
>But compressing and decompressing is not an energy efficient task. It takes a lot of work. Mechanical inefficiencies are a huge energy consumption. Gas is simply burning fuel. Yes, we should save gas for rainy days. But I hate to say that it is more efficient and cheap. There is no comparison.
You are very mistaken, the energy required to compress refrigerant is less than the energy captured and delivered if COP > 1, which is the point of a heat pump. At COP 1 it is basically heat of compression and equal to a resistive heater at COP greater than 2 the heat pump captured more heat from the environment than used to compress the refrigerant.
I am not sure if you are arguing in good faith, if so here are some of the simplest resources I can find to explain how a heat pump can exceed a furnace in efficiency even when taking power plant and transmission losses into account, with easy to understand graphics:
https://greenbusinesswatch.co.uk/cop-vs-spf
https://energyeducation.ca/encyclopedia/Coefficient_of_perfo...
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heatpump.h...
This should really be taught and drilled in lower education, the difference between heat and temperature and relationship to power, how heat engines work, etc. This stuff basically makes modern society possible and we will never progress in decoupling our power sources from use of the power which is what electrification allows which allows us to transition away from throwing carbon up in the air for energy.
Any reasons to change my mind?
Having lived in a new, high end apartment that had a heat pump for both heating and cooling for 3 years, I am very unimpressed with the tech. Running nonstop, couldn't heat/cool above/below a certain threshold. Electric bill very high. Clogged and broke a lot. If the general radiant heat and cooling from being in large building didn't exist, I couldn't see this working halfway decent in any place in the midwest. This might work for areas with less variable temperature ranges but for the midwest USA, not seeing it.
In the midwest a geothermal heat pump would work wonderfully.
Also, they are designed to run constantly in order to maintain the set temperature -- it's not like a natural gas fired furnace where it quickly reaches the set point.
Not all heat pumps are variable-speed like you describe. My own home, built in 2000, has a single-speed heat pump that kicks on 100% or off, like a regular old AC unit.
Mine is a variable speed unit, but that's not the function that I'm talking about.
Additionally, there are multiple types of restrictions on where geothermal pumps can be installed, and navigating this can add to costs.
I don't see it as a one size fits all solution, there are far too many people for whom the household/company math doesn't add up. However, I agree we should be doing fair comparison against other renewable-friendly options for all new construction. I'm sure heat pumps could win out in a great many situations, and we should use them where they do.
GP's comment was about the tech, though, and not the cost of said tech.
It's absolutely not a perfect solution for all heating needs across the globe, the the technology is far better than GP is suggesting.
My main concern is the overall long term efficiency & affordability of renewable-friendly solutions, because competitiveness in those areas is what will lead to mass adoption. The point I was hewing toward is that I feel the heat pump advocates and providers need to make it more clear which situations are best suited for that solution and which are not, because it would benefit everyone.
Note that a heat pump cooling a building is essentially the same as an air conditioner. So it's more a matter of how efficient the air conditioner you're replacing is. Cooling a house is much easier than heating, because the temperature differences are lower. In your example, cooling 95 F to 70 F is a 25 F difference, while heating 20 F to 70 F is a 50 F difference. The world record for heat is about 135 F, which is the same difference from 70 F as 5 F, a completely normal winter temperature in much of the world.
Habits are hard to break, though, and there's not much value (if any) of lowering the set-point at night during the winter months. People still do it, though, and then the unit is working overtime in the morning to reach the desired set point.
I'm glad that you're happy with your setup!
Personally, for my home and climate in the area, I disabled aux heat entirely, unless the temperature is below 0f outside, or if it hasn't reached the set point within 2 hours. Recently had some cold weather and these settings worked well for my home.
I'm using an Ecobee, configurations will vary per thermostat. The big settings for me were using manual staging to configure the temperatures to engage aux, temps to lock it out, etc.
There is no conspiracy to push broken technology on to the masses. Heat pump technology has come a long way and modern heat pumps are very good at what they do.
If someone installed a heat pump that doesn’t work in the temperature range of your location, they really screwed up. Modern heat pumps can be selected to work down to very low temperatures, and they’re installed with auxiliary heat when necessary. The design parameters aren’t a mystery.
Firstly the later typically have a higher power rating.
Secondly, if you can lead water around the house and heat via radiators or floor heating you get a much better efficiency.
It is coordinated. I wish there is more investigative research into who and why they are doing this.
You are not engaging with any of the helpful, generous replies, in fact going as far as to say that you wish you could call it ‘coordinated’.
Why are you even here if you think we are all lying shill for big air compressor?
https://trends.google.com/trends/explore?date=2021-01-10%202...
This technology connections YouTuber I've seen pop up in lots of discussions on these topics.
If you were to use all of the burners on this stove on their highest setting, it would consume more BTUs than a 6-ton Furnace! And it just vents into your indoor air: (https://www.homedepot.com/p/Cosmo-36-in-6-0-cu-ft-Commercial...)
A friend of mine just remodeled their kitchen -- they got all the permits and sign-offs, and their AHJ allowed a gas stove in the island with no venting at all. Inspector told them they should open a window if they were doing a lot of cooking. It's actual madness.
"It's my god given right to poison my family with CO and NOx!"
Yes, because it fucking works. This isn’t some network effect thing where everyone has to do it correctly.
It’s like saying diet & exercise isn’t a solution to obesity because it’s completely optional and rarely done correctly. Absolute stupidity.
One doesn't even need to look at climate impact to say gas stoves are bad, but focus the narrative on that one aspect and you can get climate deniers hyperventilating and defending their gas stovetop with statements like "you'll pry my gas stove from my dead hands". But really, economics are going to kill them all the same - induction stoves are dramatically more energy efficient, have the same benefits of fast thermal response, and don't pose a gigantic risk to life and limb every time you turn them on (or leave them off, for that matter).
Those that have the ability to use firewood to heat their homes today can continue doing so if they need to- its not a requirement to close up your chimney permanently to use one.
FWIW I am considering switching to a heat pump, but would still have natural gas fireplaces as a backup.
Using machinery for heating isn’t new. Virtually nobody in the modern world uses firewood from a local vendor to heat their homes.
These conspiracy theorist angles are baffling. Heat pumps are just another variation of AC, which is already ubiquitous. If people don’t use heat pumps, they won’t use firewood. They’ll use a regular furnace or electric heat.
A while ago I ran the numbers, and to meet UK electricity demand from wood would consume every single tree in the country in three months.
Limiting that to heating and giving up on industry would stretch that a bit, but the country is fundamentally dependent on imports to stay alive. We can't not be global.
Manufacturers are obviously pushing, but many utility companies and municipalities are too. Basically the electric car or solar panels of HVAC. It's one of those things where there are a lot of incentives for everyone involved all the way down the line.
Yeah, tl;dr: fuel price scares and the French nuclear power plant disaster, as well as government regulations.
To expand: most homes traditionally are heated by either burning something fossil (oil, gas, coal), somewhat half-ish renewable (wood pellets, straight chopped wood), by straight electricity (resistive heating) or by heat pumps (air-to-air, ground-to-air, deep-well-to-air aka geothermal). Some homes particularly in urban areas or in close proximity to a large power plant can also be heated by district heating using one of the aforementioned heat sources.
And all of these classes of heaters have their issues:
- Electricity is the easiest of the bunch from a technical point of view, but you're out of luck when the grid fails for whatever reason, you're tied to grid price hikes in some contract models (as people learned the hard way in Texas' last winter spike), there will be fuel burned as part of the generation and frankly resistive heating is wasteful.
- Wood pellet has the problem that the amount of waste (=sawdust) is finite, which means you're chopping down wood that could be used for construction and burning it instead. That is a waste of money and valuable resources when wood is scarce, fine particulate matter causes smell and health issues, and a lot of wood is unethically sourced.
- Solid-wood or coal heaters are difficult to properly fire up - most people fire it wrong (not enough oxygen / too much fuel load), resulting in higher consumption of wood, higher emissions and a danger of soot buildup which is a fire risk. Additionally, many home fires are started by people disposing not-completely-cooled ash or placing flammable objects too close to the oven or exhaust, and still a lot of people die because of carbon monoxide emissions caused by improper handling.
- Oil stinks to hell and beyond, the boilers need an insane amount of maintenance so they don't clog up, you need to ship tanker trucks to homes, there are risks of spillage and contamination, and the same emissions issues of wood apply (plus, oil generates more CO2 than gas per kWh of heat). Also, it's not renewable at all.
- Gas is relatively easy to ship around when there is a gas distribution network in place, it burns relatively clean, but carries an explosion risk and is fossil in origin (at least for the next decades that it will take to build up power-to-gas infrastructure).
In contrast, heat pumps are pretty awesome:
- all they need is a bit of electricity - a good heat pump can achieve up to 4x ratio, meaning it generates 4 kWh of available heat in the home by using 1 kWh of electricity. That also makes off-grid or local generator fallback solutions more feasible - a 20 kW heat-pump boiler needs a 5 kW generator which can be had for a couple hundred dollars instead of a massive generator unit.
- their heat sources (or rather, cold sinks) are renewable - air, local ground loops or deep wells are virtually infinite. That means, as long as your electricity supply is renewable, your heat generation also is renewable.
- Most heat pumps run at 40-ish degrees. That in turn prohibits the use of old-school convection radiators, so most installations with heat pumps tend to use floor heating which needs less energy to achieve a temperature comfortable for humans (our feet are the most sensitive part, but as heat from a convection radiator rises to the top of the room, it needs a lot of energy for a comfortably warm floor).
- they are, particularly when compared to oil heating, extremely small and don't cause emissions
- they don't need much maintenance effort to keep running, and no need for chimney sweepers either
- they don't pose an imminent risk of carbon monoxide poisoning or outright fire
Basically, the only issue heat pumps have is you need specially trained people to install them and they are short in supply at the moment since everyone and their dog got shocked to heaven in the last year of that goddamn war and heat pumps are the objectively best way to heat a home.
But seriously, it's just the next fish to fry after electric vehicles became a solved problem. Heating buildings is somewhere around 10-25% of total emissions and probably the largest remaining single factor not directly addressed by switching the electric grid to renewables, so many people concerned about climate change have converged on it.
I would never get electrical water heater, stove, and heater for that reason.
I was thinking the solution for me is to put in a heat pump and then run a backup gas generator. But that solution feels like a significant amount of overbuild. I have 3 minisplits already but they aren't valuable in the winter -- where you install your AC units isn't where you would install your heating units .. I.e. the top of my house for AC, the bottom of the house for heat.
Having multiple energy sources to defray risk is helpful.
If he's building the house new, he should strongly consider investing in designing the building envelope in a way that 20kW heat pumps aren't required. It's very possible, especially with new builds.
The models to follow are Passive House [1] and Pretty Good House [2]. There are many examples of large houses built to those standards in cold climates that use a heat pump that only draws 2kW, which could easily be powered by a generator or backup battery. This assumes that by "big house" we mean something still below ~3500sqft and not some kind of mansion.
The basics are to get the building air leakage below 1ACH50 (3-5x better than most codes, but not hard in a new build), and eliminate thermal bridging by using thick exterior insulation around the building perimeter.
First, it must be told that an off the shelf AC unit is technically speaking also a heat pump. There has been this distinction (and confusion) between AC units and (mostly) ground source heat pumps because, you know the latter actually have a water 'pump' to circulate fluid in the ground piping. Ground source heat pumps are far more expensive that AC units and are nearly impossible to retrofit in existing buildings. Hence, companies came up with a 'middle ground' solution, called air source heat pumps. In these devices the outdoor unit is much like an outdoor unit of a split type AC, but the indoor unit is basically a refrigerant/water heat exchanger with a water pump and some sensors around it. There is also a monoblock type of air source heat pump, where all components are in the outer block and you only connect the piping.
IMHO, the reason air source heat pumps are becoming popular now is because their price went down considerably during the last 5 years, whereas the price of fossil fuel heat sources has gone up. Back then when I had to choose between a gas boiler and a heat pump, the boiler was around EUR 2, off the shelf heat pump (24000 btu) was around EUR 7k and for the DIY option I paid a total of EUR 2.3k. The reason for this was that the market for air source heat pumps was underdeveloped and companies (e.g. Mitsubishi, Daikin, Fujitsu) were charging a lot more in this market segment (rich people with new houses). At some point in time, people started realizing the benefits of a heat pump over a normal AC (less units, no noise, nor air currents, better efficiency, can produce hot water, heating is decoupled from the source and more sources, such as solar can be seamlessly plugged in). Manufacturers albeit slowly responded to this demand.
Now with solar power gaining more traction, they are becoming a very obvious choice.
Companies that sell heat pumps are advertising hard. It's an easy sell for them with rising gas prices.
The US government is "pushing them" by offering tax credits for heat pump systems. This is part of a plan to reduce pollution, improve energy independence/energy security, and save citizens money on their heating bills. No secret there - politicians and public servants are excited about this and they are talking about it. They are also offering tax credits for other high efficiency heating systems, but not that many people are looking at those tax credits because buying a new high efficiency gas furnace doesn't make that much sense when you could buy a more efficient heat pump instead.
Many individual people are also talking about them because they are a great way to help the environment and save money at the same time.
And I think a lot of people just think they are cool technology as well.
I'm always a skeptic on when something gets super hyped. In this case it's more use-case specific that makes me skeptical - majority of people its 100% fit.
It's old tech, it's been around since the 1800s. The only thing that has changed is that heat pumps have gotten cheap and energy has gotten expensive.
There are applications where heat pumps cannot replace boilers - in industrial processes where high temperatures are required or tremendous capacity is needed intermittently.
However, unless your temperatures are routinely below about -20 F, a heat pump is the best choice (and even if temperatures occasionally drop below that, heat pumps are still an excellent choice because those extreme temperatures might only last for a handful of hours out of the year, during which insulation or a cheap electrical resistance heater can keep you warm).
1. The American market has a lot of incorrect perceptions of heat pumps. Debunking these makes for great viral content! 2. The IRA introduced big incentives for various electrification expenses.
The incentives are the big thing, but the public interest/controversy part is why some enhancements like heat pumps and kitchen electrification ("don't take away my gas stove!") are going more viral than, say, electric vehicles (technology connections guy has some good EV content, but it's not doing quite the same numbers)
Based on the lack of political dick swinging I don't think this is a "push".
They're legitimately good technology for certain use cases, I'm sure the manufacturers are pushing them. They are also The New Hotness(TM) and they are billed as environmentally friendly. Both those attributes are valuable by themselves to some people.
I think this is more a case of a grassroots-originated circle jerk within certain demographic bubbles.
This is great for the climate but air source heat pump technology simply doesn't work well in cold climates. Most heat pumps in the United States have 100% efficiency down to about 20 degrees F. Below that they "lose efficiency."
What most people don't realize is that "lose efficiency" = blows cool or cold air. So if you live somewhere that routinely gets that low you are likely either going to be really cold, or have to engage aux heat (often natgas or oil-based heating or electric resistance heating).
Additionally, even when operating at 100% efficiency they don't blow air as hot as traditional heating sources. So if you have a poorly insulated room, large space, or even just an unusually cold day, it will often have a hard time keeping up.
I have found that I only use my air source heat pump a little bit during the fall in New England, and I have to run aux heat throughout basically all of winter. Talking to my friends in the region who have heat pumps, they all have similar experiences.
I think we are all very eager to get off of fossil fuels but the technology just isn't there yet, and I am concerned that most people installing heat pumps today don't know the risks associated with them in extreme weather events. If your heat pump can't keep up and you didn't install aux heating you can't live in your house, your pipes will freeze, and you will generally have a bad time. If you did install and use aux heating, you may be surprised at how expensive and inefficient resistive electric heating is as it may need to run all the time.
[1] Massachusetts will pay you $10k to install air source heat pumps and disconnect from natural gas https://www.masssave.com/en/residential/rebates-and-incentiv...
Most things that are already installed are worse than the latest technology that's available.
That's not an argument against the latest technology.
2. Cites like NYC have implemented bans or limits on new gas installations, and it has been proposed at the state level as well. Other cities such as Chicago have had conversations regarding this issue, at least enough for it to get into the news and spark minor outrage.
Because of these recent controversies there has been much talk about Heat Pumps and whether or not they are able to function efficiently or sufficiently in sub zero temperatures regularly seen in the upper Midwest or North East.
The winners are consumers, the effort to reduce GHG and particulate emissions, and the drive toward energy independence (whether at the national, local, or hyper-local level).
The losers are fossil fuel extraction industries, because due to the high COP of heat pumps, far more heat is delivered per unit of energy consumed, even if that energy ultimately comes from burning natural gas at a power station. Also, the source of the energy itself gets disintermediated, since electricity can come from multiple sources, including renewables.
The tradeoffs are (for now): Higher upfront installation cost (tempered by the IRA, and potentially lower operating costs), availability of the equipment (supply chain stuff), and long delays in installation due to lack of qualified installers (and resulting high costs).
Heat pump as every heating or cooling devices, have pro and cons. This is where HVAC knowledge is nice to have, in order to have the best solutions. For example, the maintenance / obsolescence are an under estimated point when it comes to environment and savings
At a basic level, governments are full of people who have an interest in public policy, and they read publications that cover public policy matters from around the world. If the EU brings in a policy that encourages an expansion in heat pump usage, it'll probably get written up in The Economist (and a bunch of more specialised publications), and, guess what, bureaucrats and political staffers in the UK, the US, Canada and so on will read it.
There are also institutions specifically devoted to developing policy advice for national governments, and in the renewable energy space the big one is IRENA. And guess what, they're telling their member governments that, hey, if you want to screw over the Russians, meet your greenhouse targets, and save your citizens a bunch of money, heat pumps are the way to go. And as those things happen to be basically true, national governments are falling over themselves to implement policies to encourage it to happen.
I understand that its for climate benefits but it feels very coordinated.