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Heat Pump Water Heaters
- hinkley 6y agoSome jurisdictions have a rebate program in effect for these. You should look at whether your utilities company has any information on the subject.
- lsllc 6y agoIf you have a geothermal heat pump, you can install a "desuperheater" [0] to recover the excess heat for hot water during the shoulder seasons. It doesn't work so well during the winter, so you need "backup" heat such as an electric element, or a more traditional fossil fuel hw heater (and you might also want one of these as a backup for the geothermal loop depending on where you live). [0] http://www.geojerry.com/desuperheater.html http://www.geojerry.com/desuperheater.html (sorry, couldn't find a better site)
- serpix 6y agoI had a ground heat pump for several years. It could easily warm a 170m2 house plus warm water. Of the temperature went below -15c or more the electric elements kicked in to boost the pump. I could sit in the living room with a t-shirt on and not worry about heating expenses, it was very cheap to run.
- xxs 6y agoGeothermal heating is pretty standard nowadays in North Europe. Heating the house + hot water is totally doable w/o using an auxiliary resistive heater even when the temperature outside is -20C. Geothermal heat pumps would feature the extra heater (like 9kW) just in case but mine has been turned on only when it overheats the water (60C+ once per week) to reduce fauna build up.
- dzhiurgis 6y agoHeat recovery ventilators using heat exchangers have proven to be very successful too. Something like over 90% efficient. Couple that with triple glazing and you almost need no heating. What I do wonder why there aren’t more in-window air conditioners coupled with heat recovery ventilators?
- q084yn39cptyth 6y agoWe have geothermal HVAC. When we moved in we had that water heating setup, but then changed the water heater (natural gas tank). When we did, we asked about hooking up the desuperheater again and were told the energy savings weren't worth it on newer water heating units because of the efficiency. This is coming from a well respected company in the area that specializes in geothermal and heat pumps, and generally has bent over backwards to suggest improvements to all sorts of things in other ways (I also am pretty sure they installed the original system). Not sure if they were right or wrong, but my experience with a lots of these heating and cooling things is that the real world efficiencies are often different from theoretical values.
- bluGill 6y agoGeothermal water heating just barely works out in general because efficiency drops with higher temperature differentials. If you would accept you water at noticeably below body temperature it would be great (though I suspect this is ideal for bacteria growth) efficiency. If you want your water as warm as the minimum recommended temperature by efficiency experts you are already in questionable efficiency range. If you go hotter it gets worse.
- makomk 6y agoYeah, reducing the temperature on water heaters is a great way of causing Legionnaire's disease.
- lsllc 6y agoGiven that both the desuperheater and the geothermal both need backup heat, the best approach is to install a small high efficiency gas boiler with 2 zones, one as an indirect heater for the desuperheater (so it'll ensure that the hot water stays hot, but won't run if not needed) and the second zone as a hydronic loop in the air handler to provide backup for those cold nights in the winter that are below the design spec. Of course, the heat input to your house is a function of heat loss, so if the house is very well insulated and sealed against air changes, regardless of how you heat you'll save energy. TBH, since geothermal is reversible, in that it does both heating and cooling this makes it even more attractive and efficient especially in the summertime. It should be required in new construction where possible and indeed heavily subsidized to encourage it's adoption.
- gregmac 6y agoWhy aren't there integrated systems for heating/cooling? (Or maybe this exists and I just don't know the proper terms to search for) We have multiple cooling devices: air conditioning (dumping heat outside) and refrigerators (dumping heat inside). Then we have multiple separate heating devices: furnaces and hot water tanks that burn electricity or gas to generate heat. I've always thought it would be more efficient if these units were all connected with some kind of coolant loop, and a heat pump / control unit that could route heat/cooling to where it's needed. I did find a similar system for connecting air conditioning to heat a swimming pool (instead of outside condenser unit), which is pretty neat, but I'm thinking bigger. If you're going to dump excess heat anyway, might as well use it to heat water, at least.
- xyzzyz 6y agoThen, when it inevitably breaks, your house is cold, you have no hot water, and all your food is spoiled, all at the same time.
- Scoundreller 6y agoI nominate you as the new Secretary of Food Distribution.
- deleted 6y ago[deleted]
- floatrock 6y agoSystems like that are floor radiant heating using pex water tubes embedded beneath the flooring. Geothermal heatpumps circulate water loops into the ground to dump heat in the summer / grab heat in the winter. > Heat pump water heater systems typically have higher initial costs than conventional storage water heaters. However, they have lower operating costs, which can offset their higher purchase and installation prices. That's the key problem. Solar cracked this nut with the PPA -- zero upfront costs because the system is financed, you pay your monthly electric bill through the solar company, and they take a cut of the "operational savings" as loan servicing and profit. However, the PPA was an uphill battle -- it took a while for big finance to be comfortable with the long term performance of solar panels before they became comfortable doing this kind of loans. The big solar companies today are the ones who took a bet on making PPA financing possible. With home efficiency improvements, however, there are so many more variables. Whereas solar is basically the panel and the inverter, with home heating you need to factor in the construction of the home and a million other variables. If the efficiency paybacks are less predictable, it's harder to finance, so it's harder to overcome the higher upfront costs.
- mrb 6y agoIt would be neat to combine a heat pump (water heater or general heater) so that the outdoor coil (cooling down the air) is put to good use instead of being wasted cold. For example the cold coil could be cooling down a fridge or freezer. I'm not sure how feasible it would be in practice. There is an advantage in having appliances that are independently serviceable and replaceable. But then again one heat pump system cooling the fridge and heating up water is simpler and less likely to break than two separate systems (one for the fridge, one for the water heater.) Price-wise, however, the labor costs of installing one physically larger integrated system are probably high than the labor costs of installing 2 smaller systems. So many tradeoffs...
- torpfactory 6y agoThe big issue is timing: hot water, fridge use, and home heating would need to be well synchronized to take advantage of this. I.e. you don't necessarily want to make your fridge colder just because you happen to be heating water. The fridge and temperature is set so your lettuce doesn't freeze and your hamburger says solid. Your water heater turns on because you took a shower. You would need to store the thermal energy (a block of ice, perhaps), but this adds complexity and cost.
- TaylorAlexander 6y agoIf the link was optional, so they could either share heat movement or discard waste heat, then there’d be plenty of room for an algorithm to sort it out.
- teruakohatu 6y agoThese are relatively common here in New Zealand, but the upfront cost is high and there is more maintenance than a insulted electric water heater. Retrofitting one will never pay itself off so they only go into new homes. Most homes in NZ use electric water heaters with gas becoming more and more popular. Gas is only used for heating tap/shower water and cooking, not for heating the home.
- Max_aaa 6y agoConsidering that hot water does not need to be heated right away, solar water heating (Direct or via photo-electric) with an electric hot water cylinder as a backup for overcast days would result in more reliable and more long lasting system.
- teruakohatu 6y agoSome people have them here, but it is not that popular. Most of the country has a mild climate and so you would still need an electric heater to keep the tempreture constantly high enough to kill legionnaires bacteria (over 60 degrees celcius). I think over the lifetime of the system money saved in electricity would not be offset much due to installation. Most of the country is run off hydro so not much environmental benefits either.
- robocat 6y ago> Most of the country is run off hydro so not much environmental benefits either. Actually, the majority of marginal units of electricity come from gas. That means that every extra kWh you use comes from gas, and every kWh you save reduces gas usage. There are few times when the lakes are full and your marginal unit would come from hydro. The easy way to think of it is that all the hydro is already used up by other people, so your electricity usage comes from gas. Hopefully NZ gets some large solar generation, since NZ can “store“ it in lakes by reducing lake outflows during the day (I think).
- teruakohatu 6y ago
- astawertwe 6y agoThis is a big deal. When I moved into my current apartment, the thermostat had two settings, "Heat" and "EM Heat". I didn't know what they meant, or what the difference was, and I never bothered to ask. But then one month by mistake I set the thermostat to "EM Heat" instead of "Heat". And I got a $300 electric bill instead of my usual $80. "Heat" means heat pump, and "EM Heat" means emergency heat, which means direct heating, which as the article explains requires several times more energy. I won't forget that again.
- rathel 6y agoYay for another descriptively named controls on an appliance. What did people designing this think? I know it's probably in the manual. But there are people from whom you can't expect reading the instructions - not because of "fuck the manual" attitude - like guests who live only temporarily. Would a more descriptive label save them $0.01 on ink or what?
- alliao 6y agoI like the idea but I can't find a brand that I'd trust in this day and age. Whiteware goods used to last 20yrs, or people expected them to. Nowadays 5yrs warranty seems to be the timeline they're expecting people to accept. Heatpump water heater will save energy, but more parts to break. I'm sure it can be engineered to be reliable, just not sure by whom...
- TaylorAlexander 6y agoI know this is not a concept people are used to, but I’m really in to the idea of open source appliances. In that case there’d be one centralized (and forkable) project where skilled engineers from around the world could design a suitable machine. I’d love to see companies pop up to manufacture those designs the same way 3D printer companies have done.
- mrfusion 6y agoThat’s a great idea. If you had enough money you could hire engineers to make version 1 and kick it off. Or maybe you could recruit some engineers?
- TaylorAlexander 6y agoWell I try to encourage bored engineers to work on open source hardware projects. Finding a funding stream is difficult but finding engineers who want to improve their skills and contribute to society is pretty doable. I spend half of my working time on unpaid open source work that is self directed and primarily chosen based on what is fun and enriching. I have a YouTube channel where I am slowly trying to get the message out, though it’s hard to put all my theory in to words and shoot videos for it. I seem to prefer doing engineering over writing scripts, though writing scripts has its place.
- mrfusion 6y agoThat’s great! What kind of hardware projects?
- rossjudson 6y agoI visited a house years back that captured back hot water heat from the shower drain. Hot water going down the drain went through a pipe wrapped with a spiral pattern of other pipe (and fresh water from the hot water tank circulated through there). Don't know how efficient it was, but it was pretty cool to see as a working system.
- ants_a 6y agoApproximately 50%.
- Cerium 6y agoThe keyword is "drain water heat recovery". I don't know the efficiency, but you can buy one for about $600.
- abiogenesis 6y agoNice, a turbocharged shower.
- theluketaylor 6y agoHere in Canada recovering heat from the drain can be used as part of energy efficiency code requirements in new builds. They can recover quite a bit of heat, around 50% depending in inlet and outlet temperatures. Pretty good for a fully passive technology that has no maintenance or moving parts. It does require a lot of copper, so the parts are about $1000 but it's a really easy install.
- frosted-flakes 6y agoThose things are neat. I always wondered why they were wrapped around vertical pipes rather than horizontal, because intuitively it seems like horizontal would be better, but that's not the case. I looked it up and it's because falling water in a vertical pipe will cling to the pipe wall, while in a horizontal pipe it will just sit in the bottom. It's obvious in hindsight, but I've never thought about the physics of water in a vertical drain pipe.
- henrikberggren 6y agoHeat pumps are really amazing and can be used both for cooling and heating with the same hardware. If it wasn't for natural gas they would make sense for many American homes https://medium.com/hackernoon/the-magic-of-heat-pumps-fd2721a00586 https://medium.com/hackernoon/the-magic-of-heat-pumps-fd2721...
- quickthrower2 6y agoIt might solve some of the solar demand problem. Heat water up during the day when the sun is out, and then store that in an insulated tank. Have both bath water and central heating run off that.
- ants_a 6y agoMakes sense for hot water, but with central heating less so. The energy is mostly needed during the months when there is not a lot of sun, over-sizing the solar collector is financially untenable, as is large enough insulated storage to cover months of heating.
- JshWright 6y agoThat's already a thing, they just skip the intermediate steps and run the water through black pipes in a sunny spot.
- quickthrower2 6y agoBlack pipes are great, it would make some interesting calculations to compare: Pipes vs. PV taking heat pump characteristics into account, whose efficiency depends on climate. Installation costs, maintenance costs. The Pipes compete for real estate space against the PV, so if pipes are more efficient, does it off set the lost electricity (that would be more expensive, but cheaper than from the grid, but only when it's sunny and you can use the appliances at that time, unless you have a battery which is more capex, so does the interest/repayments on that cost get offset by using electric 24/7). Etc. Etc. It might need some ML to figure out the best solution. And by ML I mean linear regression.
- nickdevore 6y agoI've had mine for about a year. I put it in my garage which previously, would reach easily 100F + in the summer. This past summer, on the hottest day, it got to about 90 in the garage. When the water heater was running, it easily kept the garage below 90. I purchased the hybrid version which can use straight electricity when the heat pump won't cut it. This serves to also keep the garage cooler for the second fridge I have in the garage. I was previously on propane to heat my water, which was costing between $50 - $60 a month. During the summer, my electricity bill only went up $12 a month. During the coldest part of winter, it was at about $30 a month more. But, I pay considerably less for electricity in the winter than in the summer. Just for reference, I purchased the Rheem 65 gal 10 year warranty from Home Depot when it was on sale. This has definitely been one of the best purchases
- mrfusion 6y ago50$ a month for hot water seems really high? I’ve never gone over 20$. Anything you want to tell us?
- dsfyu404ed 6y agoWater usage basically scales with household size. GP probably isn't a single dude living in a studio apartment taking navy showers and planning his meal prep to minimize dish washing. Combine that with an electric water heater (almost always more expensive to run than natural gas) and a nearly triple digit electricity bill isn't surprising.
- amluto 6y agoPropane, I’d guess. With propane, you are paying someone to truck propane to you and pump it into your tank. You are also paying all the costs of owning and maintaining the tank. If you live in a place with reliable electricity, I don’t think propane really makes sense any more. You can get heat and hot water from heat pumps, and induction stoves work well and are vastly more efficient than gas.
- oflannabhra 6y ago
- xfitm3 6y agoIn hot climates you can also recover heat rejected from your A/C compressor, circulate water into a tank, and get a bunch of hot water for free.
- expensivepool 6y agoWe use a heat pump to heat our 15,000 gal pool in FL - we keep the temp at 94° basically year-round, minus a few weeks, and it costs only ~$150-300/mo, depending on outside temp.
- pp19dd 6y agoCan you tell me more about it? Looking into this now, but in MD. Waiting for an electrician's quote for running 220 V down there. Which heat pump did you go with, how did it turn out and all that jazz?
- expensivepool 6y agoGulfstream. It’s been great so far (couple years in)
- pp19dd 6y agoThanks much - which power range (BTU equivalent) did you get?
- senectus1 6y agoholy hell. thats more cost than our whole house of two adults and two (just) pre-teen kids every month... JUST for the pool. in fact thats more than our bill every two months (AU$400 every two months), and that's our new place which has some 80's design issues that i need to resolve. our bill should be nearly half that.
- expensivepool 6y agoYeah, but to heat a large swimming pool to near-hottub temps... not terrible. Propane would be thousands.
- abiogenesis 6y agoNote that 94°F is 34.4°C.
- 6y ago
- ars 6y agoFor even better efficiency use an Absorption Heat Pump, powered by natural gas. But they are hard to find.
- magoon 6y agoMy electric bill has gone down over 30% per month after getting one of these. Replaced a super old electric unit. Many states have rebates that an installer can have applied when getting the part from the supplier. For me this cut the whole cost in half. It paid for itself in less than a year. And now my basement is dry and cool in the summer without running a dehumidifier. You might ask, if these are so great then why aren’t people yelling it from the hilltops? They are, but nobody’s listening.
- yumraj 6y agoYou are comparing to an electric water heater. I think the cost saving is not much, from a ROI standpoint, if you have a natural gas water heater.
- koolba 6y agoHow’s it compare to a tankless gas heater?
- stevehawk 6y agoTankless heaters seem like the biggest over promise household tech I can recall in the last decade or two. I have not found over that I would even come close to breaking even on when replacing either of the water heaters in my house.
- ed_balls 6y agoTankless heaters heaters are great if you live in a small flat or don't use it extensively (living alone, half of the time taking the shower at the gym). Currently, in my flat there is only district heating which is way cheaper (lower cost, no maintenance). It's really great, should be the default in high density areas.
- lotsofpulp 6y agoNatural gas is the significantly cheaper option in my experience with residential and commercial properties, if there is a utility providing a line to the property.
- deleted 6y ago[deleted]
- mlindner 6y agoThese make no sense if there's natural gas available. Natural gas is dirt cheap (heck recently it's being given away for free in many places because it's a waste product from oil extraction).
- hyperbovine 6y agoNot true at all. My basement is a muggy swamp in the summer. I have to run a dehumidifier 24/7 else everything molds. This water heater does that as a side effect. Plus, some of us enjoy owning things that are energy efficient, and are willing to pay for it. Enjoy your global warming.
- deleted 6y ago[deleted]
- teruakohatu 6y agoIs your gas burner inside the house? Here in NZ I have only ever seen them installed externally.
- post_break 6y agoDepending on where you live you can expect a gas line fee of $20-40 a month before you use any gas. Something to consider.
- skuhn 6y agoThis was one of the factors that led me to replace two 40 gallon gas water heaters (on two separate gas lines, so $60 every month before a single pilot light is lit) with one 80 gallon HPWH. The other factor was that you have various options to get renewable electricity, from paying your utility to installing solar panels. There is no such option for natural gas.
- M2Ys4U 6y ago>These make no sense if there's natural gas available. It makes perfect sense: burning gas produces CO2 which is wrecking the climate.
- jagger27 6y agoCould you use one of these to cool your house and heat your outdoor pool?
- andoriyu 6y agoThere are heat pumps for pools as well as hybrid systems. Also extremely cheap to run. For pools, they actually beat cheap gas heaters.
- willvarfar 6y agoMy pump heats my outdoors pool in summer and the house in winter. Its more usual to have a small heat-pump just for the pool, though. These are surprisingly cheap, considering the premium on all pool parts generally. I mean, a pool roof made of plastic costs 3x or 4x more.
- m463 6y agoYears ago, I was convinced that solar hot water heaters were ridiculously efficient and paid for themselves in just a few years. Since that time, I've come to think that solar PV + an electric water heater is probably a better answer - easier to install, very little relative maintenance. Now I wonder how solar PV + a heat pump water heater compares (especially if it doubles as a cooler for a surrounding room).
- grecy 6y agoIn certain parts of the world (tons of Australia, parts of Africa) literally every single building has a solar hot water heater. They are fantastic in hot climates, and should be littering the roofs in CA, AZ, TX, etc.
- autonoshitbox 6y agoAmericans are afraid of the "third-world look" of solar water heaters they know from vacations in Europe
- grahamburger 6y agoI don't think this is true? Also for what it's worth I've spent time on the roofs of a lot of apartment buildings in the bay area and seen many solar water heaters. Newer buildings and homes tend to just have solar panels if anything, though.
- dlhavema 6y agoI guess I'm not privileged to have seen that and would mind a setup on my house. I'm in AZ
- BloominOnion 6y agoNot everywhere in Australia, you don't have to fit them but your home needs to meet a mandated minimum '6 star' energy rating. This comes down to everything in the house such as wattage per square meter of lighting, double glazing in windows etc. The biggest pitfalls here usually with solar hot water is the storage capacity, especially with a family.
- duxup 6y agoMy concern with these is always the noise. The compressor on there has to be fairly noisy.
- esaym 6y agoThere's a compressor too on your fridge you know...
- duxup 6y agoIt's pretty annoying too, and so does my air conditioner...the range of noise seems quite wide.
- willvarfar 6y agoMine hums like a fridge. Luckily, its straightforward and normal for the heat-pump to be outside or in a garage or basement, so the sound isn't in the living space. Its like: who would want a window-mounted air-con when they could have one of those white boxes up on the roof where nobody hears them instead?
- skuhn 6y agoThey are a bit noisy, but it depends on the location for your site. In a basement, maybe it doesn't matter as much (and HVAC equipment is likely to be much noisier). Current models range between 49 and 55 dBA, equivalent to a refrigerator.
- twic 6y agoThis is one of the reasons that heat pumps don't play well with high-density living. A friend who had a semi-detached house looked into getting air source heat pumps. That would have involved a big fan unit sitting just outside his kitchen window. He couldn't get planning permission, because it would also have been sitting just outside his neighbours' kitchen windows, and it's rather loud. Ground source heat pumps don't have that problem. But i live in a second-floor flat (third-floor apartment for the Americans) - where am i going to find a ground source? If i run a pipe down from my kitchen, i hit my neighbour's bathroom! There are several comments on this page suggesting using an outdoor pool has a heat source. Different worlds!
- milofeynman 6y agoI want to pump this cool air into a server closet with an outtake but I'm sure there are problems with that... Anyone tried?
- frosted-flakes 6y agoIt would probably be more efficient to pump the warm air from the server closet into the water heater room.
- agent86 6y agoWhen my water heater last needed replacing I went and got a Propane Condensing Gas Tank water heater[1]. It was a bit expensive up front, but at 96% efficiency I thought I would make up the difference on gas while enjoying the performance. It is pretty wild - we lost power for days once in the winter cold, and it brought the water back up to temperature in under 10 minutes. Even empty it can basically keep up and heat like a tankless unit would. It has a little LCD panel where you can check the stats of the unit, so I just took a look. We've had the heater on for 3430 days, it has cycled 15,584 times, and run the burner for 57 days. It has basically run about 1.5% of the time it has been on. In the future I'd consider going the heat pump route if I can get solar, but given the topology and how my house is positioned it doesn't look like I'm a great candidate for it :-(. [1] https://www.hotwater.com/water-heaters/residential/high-efficiency-gas-tank/ https://www.hotwater.com/water-heaters/residential/high-effi...
- teruakohatu 6y agoI had not heard of Condensing Gas Tank water heaters before. They are very clever. Gas water heaters are very popular here in New Zealand. Do you know how much more efficient the Condensing Gas Tank water heater is over regular gas? If I understand it correctly, the difference is that the condensing system pre-heats the cold water with the exhaust gas from the burner. https://www.hotwatercylinders.nz/images/source/Bosch_26eco_Condensing.jpg https://www.hotwatercylinders.nz/images/source/Bosch_26eco_C... Did you compare costs of a regular gas heater vs. condensing?
- elric 6y agoBest case, a condensing heater uses 20% less gas than a conventional one. But there are some caveats...in order to condense the exhaust fumes, the returning water has to be cold enough. Low temperature radiators or underfloor heating are best for that. If you have huge, old, cast iron radiators that get super hot and stay hot for a long time, there probably won't be much condensing going on. Basically any time you see white smoking coming out the flue, it's not condensing.
- agent86 6y ago
- WaitWaitWha 6y agoI do not understand why anyone uses water tanks at all. The tankless or demand-type water heaters tend to be more energy efficient, take significantly smaller space, less parts, and have been in use successfully since the 19th century. Am I missing something?
- Negitivefrags 6y agoThey take longer for the water to heat up. And a heat pump is going to beat it hands down.
- imtringued 6y agoI don't understand. One of them takes hours the other one produces hot water as soon as you open the tap.
- kevstev 6y agoThere is a small "spin up" time to get everything hot and hot water pouring out. This is pretty minimal IMHO, and dwarfed by the amount of time it takes to get cold water flushed out of the pipes. Recirculating systems exist to prevent this problem- for tank/tankless systems- but according to some have drawbacks around increasing wear on your pipes. I have a natural gas tankless system and find this to be a non-issue.
- serpix 6y agoEnergy storage. A tank of water can be used to store and release heat from a multitude of sources. Compost, wood, solar, wind, electric, heat pump, gasoline.. The best part is hybrid sources. Couple a wood burner to a solar heater and a heat pump and run the pipes through a fireplace as well. Combined with an intelligent mixer you can heat up your shower and tap water and your house.
- sacred_numbers 6y agoI don't know if this is the reason, but one potential advantage of tank water heaters is the ability to use off-peak power. This can be a big cost advantage, and even if it's less energy efficient it can theoretically be better for the environment by allowing water heaters to act as distributed renewable energy storage. At the moment, though, the efficiency savings probably make tankless water heaters a bit more environmentally friendly.
- reyoz 6y agoI put in a Sanden heat pump to replace an old electric gravity water heater 1.5 years ago. Based on power meter data it uses 30% of the energy of the old system on average. This is probably understated as hot water consumption has gone up as the new system and new pipes increased pressure and flow. I say on average as there is seasonality to the energy consumption. I live in a temperate climate, no snow. We run it at night to take advantage of cheaper separately metered electricity rates ('controlled load'), it could be run even more efficiently during the day, but at higher cost. This and replacing the old gas ducted heating with reverse cycle air conditioning has allowed us to stop using gas, saving the fixed $~30/month service charge. Eventually the additional of solar will further increase our use of renewables.
- dirtyid 6y agohttps://www.youtube.com/watch?v=omivdhxdGv0 https://www.youtube.com/watch?v=omivdhxdGv0 Matt Risinger has some approachable videos to building technology for those interested.
- JackPoach 6y agoHeat pumps are nothing new. They are not wide spread for a reason. It's weird how old ideas get a new life over and over again. My pet peeve is that these ideas are presented in an overly simplistic way that simply aren't true. "Did you know that you can get free electricity by simply installing solar panels on your roof?" Or "Cut your utility bill 50% by harnessing the power of wind". We know about heat pumps for 100 years. There's a reason why most heaters use gas or electricity - it's cheaper and more simple in installation. There are a lot of enthusiasts who can do things well with their own hands, including sourcing materials, so it's really cheap and simple FOR THOSE FOLKS. But for regular folks these things tend to cost more even for totally proven and technically viable technologies - solar, heat pumps, passive house, water harvesting, etc.
- bkovacev 6y agoI moved into an apartment that has a Gree Versati Pump, and it's super neat because I can control it via modbus and raspberry pi. Electricity bill decreased tremendously when I moved.
- deleted 6y ago[deleted]
- alkonaut 6y agoIsn't this just a normal water heater? Apart from the very simplest models that you might install in a small cabin or separate building (direct-electric or maybe gas powered) isn't this is what you'd normally install in a new house for the last 30 years or so?
- rini17 6y agoNo, normal heater heats water directly using supplied energy, while heat pump works like fridge or AC in reverse - it pumps ambient heat to the water using smaller amount of energy. Perhaps in some locations they install it in new houses as a standard, but I doubt it, it is more expensive.
- alkonaut 6y agoI guess it depends on where you live. In Northern Europe it's been the default for a very long time, but so has triple glazing and a foot of insulation etc (For obvious reasons). Heating is a large part of living costs and a 30% efficiency increase pays off in no time not least because the hot water is used for space heating as well as for household water. For that reason you'd expect the same to apply for parts of northern USA and Canada.
- joking 6y agono, this one uses the same principle of an hvac, to heat the water with around 1/3 of the energy needed with a resistance. so far, are very common in new buildings, as you can use the same heat pump you use to climatization, to also heat the domestic water.
- alkonaut 6y agoYes my heater is a heat pump and it has been for 30 years. As have all my neighbors’ heaters. Because it’s cold where we live and we use it for heating the whole house (hot water for radiators too). I didn’t think anyone in cold climates or even moderately cold (e.g continental Europe) would use a direct heater, at least not if they have hot water radiators.
- TopHand 6y agoI live in one of the most continuously windy parts of the nation (US state of WY). In the winter time, the heater, a ground source heat pump struggles most when the wind is blowing. I've often wondered if a hybrid heat pump system could be built that drives the compressor and circulation system directly from the mechanical action of a wind turbine rather than first converting the wind energy to electricity, then goes back to drawing from the mains when the wind is still. My thought process is that you would lose energy by first converting to electricity, then converting electricity to mechanical motion. If someone out there likes this idea, and wants to pursue it, I hereby release it to public domain.
- ptspin 6y agoHere is some information on this concept. https://solar.lowtechmagazine.com/2019/02/heat-your-house-with-a-water-brake-windmill.html https://solar.lowtechmagazine.com/2019/02/heat-your-house-wi...