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You and the planet need a heat pump
- ars 5y agoSomething I would like is a tool where I could enter my costs for electricity, natural gas, and efficiency of my boiler and a new heat pump I'm considering. I'd like to see if I'm really saving energy (and money) doing this. And how long the payback period is for buying new equipment.
- jqpabc123 5y ago* ... not by pumping cool air in, but by pumping warm air out.* Technically not correct. A heat pump does not pump air in/out of a building. It pumps a refrigerant around in a closed loop. Part of this loop is inside and part is outside. When used for heating, the efficiency of a heat pump system declines as the outside temperature drops. At a temperature of around 32F, a heat pump essentially becomes useless. As a result, most have an auxiliary fallback heat source.
- lasson 5y agoHow do freezers work if heat pumps stop working at 32F?
- throwaway0a5e 5y agoFreezers use a different refrigerant that gives them a different working temperature range. Additionally, for proper efficiency the key components of the system need to be sized for your target temperature and the temperature range of your ambient air.
- jqpabc123 5y agoWith heat pump systems, "inside" is the temperature being controlled. "Outside" is uncontrolled --- it's where heat is being dumped to or pulled from. Don't confuse the two. The efficiency of a home heat pump declines as the air temperature outside the home drops. A freezer is working in reverse so it's efficiency declines as the air temperature outside the freezer box rises. Neither a heat pump in an Alaskan winter nor a freezer sitting on a Florida back porch in summer are operating very efficiently.
- MauranKilom 5y agoI believe the point was that both a pump for heating in winter as well as a fridge/freezer try to move energy from the colder to the warmer side. Seeing as freezers can successfully extract energy from the side that is below freezing, it stands to reason that the same should be possible for a "keep your home warm, even in winter" heat pump. Now, the original claim of "heat pumps don't work below freezing" is trivially wrong (and so the question by lasson was justified), but the overall point is that heat pump efficiency gets worse the more you need it in the case of keeping your home warm.
- jqpabc123 5y agoSeeing as freezers can successfully extract energy from the side that is below freezing... Invalid assumption. Whether it can or not depends on the environment. Most ordinary freezers are designed to operate within a relatively luxurious temperature controlled in-door environment. Stick one in the sun on a Florida back porch in August and you may well discover it can no longer successfully "extract energy from the side that is below freezing". Same thing (only in reverse) can happen with a home heat pump in an Alaskan winter. There is another important element here --- energy loss and insulation. At a certain temperature (whatever it may be), the energy lost to the surroundings will start to exceed the capacity of the heat pump. At some point; speaking in practical terms, the heat pump becomes essentially worthless. You need either a bigger heat pump or you need more insulation to stop the loss --- both of which cost money and can't be obtained/installed immediately.
- Siecje 5y agoWhen the heat pump can't keep up you use resistance heating in the air handler. Since this only runs for a short period of time it doesn't make a big difference in cost.
- deleted 5y ago[deleted]
- DiabloD3 5y agoOlder ones stop working at around 32F. Modern ones meant for colder climates start losing efficiency at 0F. I live in Maine, we rarely get nights that are subzero, my heat pump works fine except for those 3 or 4 nights out of the year. The heat pump dramatically decreased my power bill vs baseboard electric.
- sokoloff 5y agoHeat pumps in heating mode lose efficiency on a continuous (with lowering temperature) basis; the colder it is outside and/or the hotter output (air or water) you want to get from the unit, the lower efficiency they have. https://www.researchgate.net/figure/e-efficiency-of-an-Air-Source-Heat-Pump-at-different-ambient-air-temperatures-and-with_fig1_266471673 https://www.researchgate.net/figure/e-efficiency-of-an-Air-S...
- teruakohatu 5y agoThat is true, but the curves have improved dramatically since 2006 (when that graph you linked to was posted). At 0C they are still much more efficient than electric.
- lsaferite 5y ago> At 0C they are still much more efficient than electric. Are you referring to resistive heating?
- derkoe 5y agoCan confirm that. Our heat pump (cheap all-in-one, 8 years old) works down to -10°C (14°F) without issues. Modern ones work down to -20°C (-4°F). Water based heat pumps work with any outside temperature. In any case a heat pump is the cheapest way to heat a building.
- sokoloff 5y ago> In any case a heat pump is the cheapest way to heat a building. That very much depends on the cost of your electricity and fuel. In MA, where I pay about $0.20/kWh and around $1.60/therm (both delivered), natural gas is around 2/3rds the cost of a heat pump in the coldest months (and loses only slightly in the shoulder months, when the heat pump is more efficient but you don’t have as much heat loss).
- wernerb 5y ago33F is 0 degrees celcius for those lucky enough to have enjoyed the metric system
- michaelcampbell 5y agoWell, 32F is 0C if we're going to go that route.
- yardshop 5y agoWell, also, 33F converts to 0.55555(etc)C, so if one's device didn't show fractional degrees and didn't round normally, 33F would look like 0C. But yes, 32F is 0.0C.
- arpinum 5y agoModern heat pumps, for example by Mitsubishi and sold in the UK, maintain a COP > 2.5 at -7C.
- earleybird 5y agoIf you have more details I'd certainly appreciate it. We're running a now 25 yr old whole house forced air system - 4 ton. Fuzzy memory but as I recall it probably has a CoP of around 16 with defrost cycles when the temp goes below +5C. It has been mostly maintenance free for those 25 years excepting on time when it started icing up - needed a recharge of refrigerant as it seemed to be a bit low - tech figured a slow leak somewhere but never found it. The system works fine and my best guess is that it is somewhere around 3:1 in favour of heat pump over resistive heat (electric baseboard or radiant panels).
- pengaru 5y agoEvery "air conditioner" is a heat pump, the only newish development for the US is for reversible ones to become more common that can pump the heat in both directions. I don't understand why there's been so much brouhaha over heat pumps as of late, it's nothing new.
- toomuchtodo 5y agoBecause air source heat pumps are the only efficient way to electrify HVAC besides heat pump boilers. Climate change mitigations (in this case, gas->electric) and all that jazz.
- orzig 5y agoHaving just bought one, I think they have recently gotten a lot more efficient, and/or cheaper. Several installers couldn’t name any options, but the more savvy ones were talking about all the new manufacturers in the game
- gwbas1c 5y agoThey used to work poorly in colder climates like the northeastern US. Newer models are better able to handle sub-freezing temperatures.
- brightball 5y agoThe integrated systems with a computer controlled thermostat and multi speed fans have tremendously helped.
- throw0101a 5y ago> I don't understand why there's been so much brouhaha over heat pumps as of late, it's nothing new. It is something new for the mainstream American consumer.
- pengaru 5y agoBut that's simply not true, air conditioning has been ubiquitous in the US for decades. They just didn't call it a heat pump, but it's a heat pump. This is just marketing bullshit AFAICT.
- powera 5y agoYes, but ... At a high level the article is correct. At a tactical level there are a few issues: * If you don't have a "geothermal" system, heat pumps aren't economical in regions where it gets below 0F/-20C. * There is a 20 year depreciation cycle for furnaces, and it doesn't make sense to install them at a significantly faster rate. * You lose a lot of the efficiency benefits when the electricity is generated from burning fossil fuels elsewhere. And we are nowhere near having enough electricity from solar and wind to heat houses in the wintertime.
- danhor 5y agoRegarding the last point: Together with the 20 year deprecation cycle, an expansion* of heat pumps makes sense now in anticipation of higher buildup of renewables as well as creating additional electricity demand, making construction of new renewable power sources more attractive. * I only know the numbers for germany, where even in new buildings there are a lot of fossil furnaces getting installed still. Replacements in older houses also usually don't switch to a heat pumps, pushing both numbers >80% would already be a major achievement in my book.
- PaulDavisThe1st 5y ago> heat pumps aren't economical in regions where it gets below 0F You haven't defined economical but here's a quote from Mitsubishi: "Hyper-Heating INVERTER® (H2i®) technology which can provide up to 100 percent of heating capacity at 5° F and continue operation down to -13° F even without auxiliary heat. Select units equipped with Mitsubishi Electric’s H2i plus™ technology can deliver up to 100 percent heating capacity down to -5° F"
- sparker72678 5y agoHeat Pumps are great, and the latest generation of variable speed units are really cool and our most efficient ones yet. Still, for heating, especially in really cold climates, a Heat Pump is going to have a hard time competing against other approaches, in efficiency, efficacy, and cost. The latest gen of "ductless" or "mini split" units are awesome *AC* units (efficient, quiet), and I'd definitely recommend checking them out for cooling. If you're somewhere that it doesn't get too cold in the winter (lows in the mid-20s at the lowest), you might be able to tolerate using one for heating, but any colder and you're going to need another solution.
- pbhjpbhj 5y agoSurely mid 20-s, 25°C ,is really hot? Where is that a winter low.
- hanklazard 5y agoFahrenheit not Celsius.
- reverend_gonzo 5y agoFahrenheit.
- mckirk 5y agoIn places that use a silly system called 'Fahrenheit'.
- hinkley 5y agoThe laws of heat engines are governed by the relative temperature on the hot and cold side. It's easy to push a little water uphill, but beyond a little it becomes a progressively more farcical exercise. Cold and humid seem to be the worst combination from reviews I've seen for minisplits, because the second biggest problem is heat transfer, and transferring heat through ice is very inefficient. Every time the ice begins to insulate the coils, you have to run the system backward to heat the pipes above freezing and melt off the buildup. Not only does that lower the efficiency of the system but eventually it limits the duty cycle, because you can't be thawing and pumping at the same time. And so you are attacked from all sides by both physics and logistics.
- politelemon 5y agoI don't know how true this is since I'm no expert, there's a YouTube video explaining why heat pumps may not be so simple a solution at least in the UK https://m.youtube.com/watch?v=GhAKMAcmJFg https://m.youtube.com/watch?v=GhAKMAcmJFg Interestingly the prediction he made, regarding gas prices, did come true.
- RobinL 5y agoI live in the UK. Last September, I bought an air-to-air source heat pump for environmental reasons, to reduce our use of gas for central heating. I did the calculations and knew when we bought it it wouldn't save much money (you get a 3-4x efficiency improvement, but electricity is 3-4x the cost of gas, at least at September's prices). Our main family room/kitchen is the largest room downstairs, and the only one we heat during the day in the winter. So rather than figure out the complexity and additional cost of an air-to-water, it seemed logical to dip our toes in with something simple. It's been great. Our gas usage is less than half what it was the previous year. The room heats up faster in the mornings, so there's no need to have the heat on before we come downstairs. On cold days this winter, we were heating the whole downstairs for about 15kwh/day, meaning we're getting roughly a 3-4x COP real-world (closer to 4 i think, but have no way of precisely measuring). If I'm feeling chilly, I can sit directly under it in a nice warm breeze. It cost £2,275 installed. The model was the Daikin-FTXP60M. (Recognise that this does not necessarily undermine the argument in the video. But I do find it odd air-to-air source heat pumps are not considered more often in the UK) Also interesting to compare this relatively modest investment with an electric car. Very roughly, the carbon savings we're seeing are comparable to the savings from replacing 10k miles per annum in an ICE with an electric (I think, rough back-of-the envelope calculation!).
- AitchEmArsey 5y ago> I do find it odd air-to-air source heat pumps are not considered more often in the UK Could be due to housing density and the reputation for noise, though I'm not sure how well-deserved that really is. Mostly I just think it is a mismatch between the age of housing stock (and the pre-existing heating solutions) with incentives. If I were building a new house I wouldn't bother with a gas supply and would use a ground-source heat pump combined with underfloor heating - but retrofitting that to my 150 year old house is never going to be cost effective versus a boiler. For residential developments, the government should just mandate no new domestic gas supplies and be done with it.
- linuxlizard 5y agoI _just_ ripped out our ~10yo heat pump at home, installed a fully gas furnace. The accursed thing was so loud and it sat right outside my office. When working from home over the winter, it would fire up and drown out any conversation in my office. I gladly ripped it out and danced on its grave.
- pornel 5y agoModern heat pumps can be under 55dB. I've had PCs louder than this.
- akvadrako 5y ago55db is not quiet -- that would be the loudest thing in my house. But shouldn't these things be in a basement or utility room?
- timbit42 5y agoWhich brand?
- mdoms 5y agoThe American reluctance towards both heat pumps and induction hobs is very puzzling to me. Both systems are commonplace enough that they would be the default option for any new build or replacement system in my country, unless you have special requirements. I understand the issues with very cold temperatures, and I'm curious what proportion of American households would expect to see outside temperatures below -17C/0F - I doubt it would be enough to explain the reluctance but I could be way wrong.
- NonEUCitizen 5y agoWhat country are you in and what are the major brands of heat pumps used there?
- mdoms 5y agoNew Zealand. The major brands are the same as everywhere - Mitsubishi, Panasonic, Fujitsu, LG, Daikin etc.
- fy20 5y agoI'm building a house in Northern Europe (-25C / -15F). Those are both the default options here too. Modern air source heat pump systems (e.g. Daikin Altherma) are quiet due to variable speed compressors, work in heat pump mode down to -25C and have built in backup heat if it goes below that.
- tpmx 5y agoHeat pumps are and have been very common in Sweden for the past 20 years or so, ever since our silly government started a) exporting electricity to Europe and b) started shutting down perfectly fine nuclear plants, and thus raised the price of our once insanely cheap electricity. Lots of houses here used to be heated using resistive, electric radiators, through the 70s-90s. Now most of those houses are primarily heated using heat pumps. Mitsubishi is the most recommended manufacturer by local heat pump aficionados - yes, there kinda is such a thing... Swedish language forum: https://www.varmepumpsforum.com/vpforum/index.php?action=forum https://www.varmepumpsforum.com/vpforum/index.php?action=for...
- BooneJS 5y agoWe're building a house in Wisconsin soon. We think that ground-source geothermal is required for efficient electrical HVAC without gas, but if we can save a ton of $$$ and go with air-source heat pump, that would be awesome.
- faitswulff 5y agoFellow midwesterner here. The last time I looked into it, heat pumps were significantly less efficient in cold temperatures. Is that still the case?
- veemjeem 5y agoStill better than electrical resistive heating (space heaters) which has a COP of 1. Even when it's super cold outside, heat pumps with a HPSF around 10 would still have a COP around 2. See the graph: https://www.researchgate.net/figure/e-efficiency-of-an-Air-Source-Heat-Pump-at-different-ambient-air-temperatures-and-with_fig1_266471673 https://www.researchgate.net/figure/e-efficiency-of-an-Air-S... Of course space heaters are far easier to move around the house compared to a mini-split system and would use less power if you only plan to heat a small room.
- bryanlarsen 5y agoThat data is really old, modern heat pumps do much better at low temperatures.
- throw0101a 5y agoIt depends on the heat pump. If you get a mini-split, and have decent insulation, they can work down to -20C: * https://www.mitsubishielectric.ca/en/hvac/professionals/fs-series https://www.mitsubishielectric.ca/en/hvac/professionals/fs-s... * https://www.mitsubishicomfort.com/articles/what-is-a-heat-pump https://www.mitsubishicomfort.com/articles/what-is-a-heat-pu... * https://www.fujitsu-general.com/us/residential/benefits/year-round-comfort.html https://www.fujitsu-general.com/us/residential/benefits/year... Some folks using them in Alaska: * https://www.nrel.gov/news/features/2021/even-in-frigid-temperatures-air-source-heat-pumps-keep-homes-warm-from-alaska-coast-to-us-mass-market.html https://www.nrel.gov/news/features/2021/even-in-frigid-tempe... If you get a heat pump that looks like the 'traditional' external AC unit (giant cube), those tend to work down to about +5C. Not sure how much more they cost above a 'regular' air conditioner: * https://www.lennox.com/products/heating-cooling/heat-pumps https://www.lennox.com/products/heating-cooling/heat-pumps The Technology Connections channel has a couple of interesting videos on the topic of heat pumps: * https://www.youtube.com/watch?v=7J52mDjZzto https://www.youtube.com/watch?v=7J52mDjZzto * https://www.youtube.com/watch?v=7zrx-b2sLUs https://www.youtube.com/watch?v=7zrx-b2sLUs He has a video entitled "How to calculate when heat pumps make financial sense (and other heat pump follow-up thoughts)": * https://www.youtube.com/watch?v=BRdq2ExLJns https://www.youtube.com/watch?v=BRdq2ExLJns NR Canada has a "AIR-SOURCE HEAT PUMP SIZING AND SELECTION GUIDE": * https://www.nrcan.gc.ca/sites/nrcan/files/canmetenergy/pdf/ASHP%20Sizing%20and%20Selection%20Guide%20(EN).pdf https://www.nrcan.gc.ca/sites/nrcan/files/canmetenergy/pdf/A... Financially speaking you're going to have to break out a spreadsheet and plug numbers in: (natural) gas prices, electricity prices, efficiency of the units, etc. Doing a search for "heat pump calculator" may get you started.
- sokoloff 5y agoI'll be replacing an aging (1950's) boiler this summer. I would love to get an air-source hydronic heat pump (air-to-water heat pump). Even with a $10K rebate, it's far more cost-effective to go with a modern gas boiler (which has its own $2750 rebate) and I have no worries of ~72 hours/year of being unable to maintain temperature. (That's not that big of a worry for me and wouldn't be a blocker, but it's a small inconvenience.) Basically, the heating contractors know the rebate amounts and, unsurprisingly, bake that into their bids. I can't really blame them for following the incentives, but it means that the energy-savings incentives don't have the intended effect.
- bertil 5y agoThe incentives are encouraging people in trades to learn about how to set-up such pumps and encourage their clients to get one. That sounds like it’s working as intended.
- sokoloff 5y agoThat's a fair point! By the time it gets to the end user's financials though, a modern gas boiler still ends up being far more attractive economically (in the land of $0.20/kWh electricity), which undermines the pace of the transition.
- PaulDavisThe1st 5y agoWhen the air-source heat pump is coupled to a good size PV array, the attractiveness equation starts to look a little different. You are never going to generate your own gas; even if you can't generate all the electricity you need for heating, you can generate a notable chunk of it (and banking summer-time excess generation can reduce your heating bills to close to zero).
- syshum 5y agoNot every lot, or every location is good for PV, further lots of utilities are working very hard to make net-metering very unattractive. They do not want to pay home owners Retail prices for electricity (and I do not blame them)
- KyeRussell 5y agoCan anyone explain the recent fascination with heat pumps? I first noticed it with Technology Connections. Here in sunny Western Australia heat pumps have been the norm for a long time. Our climate has historically been dry enough for evaporative air conditioning to work as well, but for some reason (/s) the climate is changing such that this is increasingly not the case. That said IIRC these units have been common in my life for decades, so I assumed that the rest of the world had cottoned on.
- sokoloff 5y agoIn a heating dominated climate, heat pumps have been slower to catch on due to declining efficiency and performance exactly when the heat loss of the building is the highest. (The same effect happens to an extent in heating dominated climates, but it's more rare to have 72 straight hours of outside air temp 20°C hotter than desired inside than it is to have 72 straight hours of outside air temp 20°C colder than desired inside. Even when those conditions exist, having the inside noticeably cooler and drier than outside is still relatively comfortable, while having an inside temp of 15°C is somewhat more uncomfortable.)
- frxx 5y agoFunny thing about heat pumps is, that they often operate with over 100% efficiency. Took some time for me to wrap my head around it.
- akvadrako 5y agoNothing operates over 100% efficiency, it's just a trick. It would be like saying your gas boiler is 10000% efficient because of how little electricity it uses. What you are using as fuel is the heat in the outside air.
- SigmundA 5y agoSorta like saying house with solar panels is over 100% efficient, technically true when measured against grid input. A air source heat pump is a solar assisted heating device pulling thermal energy from outside air (which is heated by the sun) into your home using electricity to gather it and move it inside. Heats pumps combined with solar panels is a a great combo BTW. Efficiency is always measured relative to something and cannot be over 100% in a closed system, heat pumps are not a closed system so no laws of physics are broken.
- hedora 5y agoYeah, but heat out / electricity in is 5, but for an ideal (perfectly efficient) electric heater, is is only one. It's one of those sufficiently advanced technologies that seems like magic. Like, what if we powered a sufficiently efficient sterling engine with it, and used that to spin the compressor and fans? It's not obvious that it isn't a perpetual motion machine or some commercially available version of Maxwell's demon or something.
- kumarvvr 5y agoDepends on your calculation. If you are calculating the energy input to the system vs. heating output of the system, then yes, it will be more than 100% efficient. However, if you are calculating total energy input to the system vs. heating output of the system, then you are at less than 100% efficiency. The heat in the atmosphere, is also due to some energy consumed somewhere, whether man made or not.
- veemjeem 5y agoSadly most popular window a/c units don't have true heat pump abilities. Usually the heating portion of window units use resistive heating.
- Siecje 5y agoAir Conditioners are heat pumps, a water pump moves water and a heat pump moves heat.
- archi42 5y agoHeat pumps are just half the story; properly insulating buildings is essential as well. And for older houses, the effect can be tremendously huge. E.g. we're planning to cut the energy requirements of our house to about 20% (no typo). And that will then be supplied by a heat pump. Sadly, all this is immensely expensive AND takes a few decades to financially amortize. Which means for people with lower incomes, who would benefit the most from this, still have to burn money to stay warm. :/
- _spduchamp 5y agoAbsolutely this! You have to seal and insulate when switching to heat pump. We just switched our house HVAC to heat pump, and there is no way the heat pump would be able to keep up with the heat loss had we not added an extra layer of insulation to the exterior of our house. Insulation is passive energy savings, so it just makes the most sense to focus there first.
- hedora 5y agoYou can get pretty big heat pumps these days. If you told the person that sized your heat pump you had a religious objection to insulation or something, they would have just stuck a bigger unit in (greatly reducing your quality of life and increasing your power bill, of course).
- alliao 5y agomind if I ask how do you tackle external insulation? is it a common thing done over there?
- _spduchamp 5y agoI wouldn't say it is common, but there are more and more architectural firms focusing on sustainability. We hired a local sustainable architecture firm when we decided to do our reno. They come through the house with a thermal camera and found huge heat loss out our old plaster walls on the 2nd floor. The solution was for contractors to remove siding, add external vapour barrier, insulation, and then we did wood siding on that. Attic was already well insulated. The results look great and and house is super comfy now. No more drafts.
- ars 5y agoI've never understood why https://en.wikipedia.org/wiki/Absorption_heat_pump https://en.wikipedia.org/wiki/Absorption_heat_pump are not more popular. They are even more efficient than electric ones.
- akvadrako 5y agoI had an ammonia absorption fridge, it was great how quiet it was. Sadly, they are rather expensive and it broke after a few years.
- AussieWog93 5y agoEvery single time I see these articles about efficient heating/cooling technology, it reminds me of just how plainly _dumb_ a lot of the systems we have are. Loungerooms with no doors, so the split system on the wall has to work 3x as hard to cool half the bloody house. Ducted heating/cooling without any valves, so your choices are either "heat up every room in the house", "get up on a step ladder to close off each vent manually" or "be cold". Cheaping out on insulation to knock a grand or two off of your million dollar new build. Just like in the software world, I suspect we'd be able to make massive efficiency gains just by actually engaging our brains. No special technology required, nor specialist knowledge. Just think about things for two seconds before putting in the semi-permanent installations.
- hedora 5y agoThe insulation thing particularly surprised me. We had to repeatedly insist on doubling the material cost to get the next step up for sound and noise insulation. The material costs were rounding error. I can't even remember what the increase was.
- AussieWog93 5y ago> We had to repeatedly insist on doubling the material cost to get the next step up for sound and noise insulation. The builders might have been saving you from yourself there, actually. I know at least one "acoustic" insulation product on the market (worked on by my old man before the mass layoffs at CSR/Bradford) isn't actually better at noise reduction than other products (funnily enough, it was measurably worse than some of the other, more expensive batts); just they've specced it as such and advertised it on the packaging.
- BizarroLand 5y agoThey make smart dampers that can help close off the heating and cooling to rooms. They're a little pricey but might be worth it if you have a large house or if you care more about energy efficiency than upfront cost. Here's one type: https://www.amazon.com/Zone-Damper-Round-Professional-Grade-Zoning/dp/B01DOB7OIC?tag=smarthome01-20 https://www.amazon.com/Zone-Damper-Round-Professional-Grade-... For total control you would need 1 of those for every vent in the house, plus wiring, installation, and a controller for it all, so it would be a few grand at least, but if you had a few rooms that had issues with hot-spotting or cold-spotting and controlling the temps evenly were difficult, it might be a good option for you. You could also try something like this: https://www.amazon.com/Flair-Compatible-Honeywell-thermostats-Assistant/dp/B07TJD4JGN https://www.amazon.com/Flair-Compatible-Honeywell-thermostat... and the relevant temperature sensing pucks to do the same thing for a few rooms easily.
- tgsovlerkhgsel 5y agoSince heat pumps will likely be bidirectional, this will have the side effect of making air conditioning (or rather in general, active cooling) available to populations that didn't have access before. Whereas they didn't have a choice previously, they'll now have the choice between using energy and sweating, which will likely increase energy usage in summer. OTOH, sunny days will likely have plenty of energy available due to solar, and it will avoid inefficient workarounds like mono units (air conditioners where the hot side is cooled with room air that is then exhausted through a hose typically stuck through a poorly sealed window - it's as inefficient and annoying as it sounds, but often the best you can do in a rented apartment in Europe).
- anonuser123456 5y agoHeat pumps are awesome, with the exception that they seem extremely prone to poor installation. My brother had 16 callbacks on his 20k heat pump install. Every time, the system had to be recharged with a complete load of the refrigerant (which is like 2000x GWP of CO2). Basically the installers didn’t bother with a torque wrench and just hand tightened all the connectors. The broke every single one, and the install company would only replace one at a time.. then it would leak.. then they replaced another etc.
- hedora 5y agoComplain to the licensing board / epa.
- alliao 5y agohave you tried washing one though? YUMMY. I do it yearly, but I suspect I'm breathing black spores 4 months in a year
- lsaferite 5y agoMy HVAC technician does that for me along with checking line pressures and cleaning in air handler as well. But I also don't change my own oil on my car, so YMMV.
- aaron695 5y ago
- cheradenine_uk 5y agoNo mention of the _disadvantages_ I see; specifically - efficiency is related also to /flow/ temperature. Which is much lower than the gas boiler it might replace - so you need big emitters (large radiators, Under-floor-heating) - and good insulation What might make 100% sense in a new build where you can design for these factors, but be awful in many existing homes.
- infogulch 5y ago"temperature control" is a general tool required for lived spaces. Heat and cool the house. Heat water. Cool the fridge and freezer. I suspect that there's a lot of wasted energy pumping heat from your groceries twice. It seems dumb to pump heat to the outside then turning around and running your water heater. What if there were a centralized temperature control distribution hub and pump, so you only needed one for the house that would serve all of these applications?