If you’re here to look at (or join) all the people who want to tell you that they think heat pumps aren’t good, here’s the brass tacks: Heat pumps are the most efficient way to use *any source* of energy - including fossil fuels - for heating buildings in almost all cases; recent improvements in Air Source heat pumps have meant this remains the case in all but the most extreme temperatures. While energy costs to the end-user may be out of whack right now - sometimes more resource-intensive energy is cheaper, for better or worse - it is factually the case that modern heat pumps allow us to RIGHT NOW reduce the amount of fuel we need to consume (a good things for various reasons), and make electrification easier as we go on.

While I agree with everything you said there is something even more important especially in the USA. Insulation. Insulation earns back the investment easily (especially with the current rising prices) and will also reduce the need for heating meaning your heating pumps won't be on as often and that IF there is a failure your house will hold on to the heat inside of it.

This is only tangentially related to the topic, but please learn how to use alternate sources of heat before there's a winter calamity of some sort. My old subdivision had a week long power outage during an unusual winter event, and although everyone had a gas fireplace, they were electrically operated so nobody used them. It turned out almost nobody knew there was a battery harness in the service panel below the fireplaces where you could install a pair of D batteries and get pretty good heat (at least in one room). Nobody read the instructions that came with the stove / oven, either, where it details how to override the electronics and light the thing with a match.

As a Finn where we’ve been using mini splits for heating for 2 decades, the most important thing is R32. Nothing gets even close to it in performance for heating in cold climates. According to our national laboratory, the second most important component to performance is the name Mitsubishi on the front of it, for some reason.

I own an HVAC company in Ottawa, Canada (MURPHY HVAC INC) and we specialize in air source heat pumps installations. Mostly Mitsubishi Hyperheat units that can produce heat down to -30°c or -22°f. The inverter technology is pretty awesome and we've helped clients save thousands in heating costs. Plus we have government rebate programs where people can get up to $5000 back, making this really expensive equipment more affordable.

In the 1960s, my aunt and uncle lived near Colorado Springs and had two "cutting edge" (for the time) innovations: 1) Recursive air ducts under the foundations of their home to provide cool air for summer and 2) A solar chimney to draw the cool air from the ducts into the house during summer and provide heat in winter. I well recall my uncle boasting that he paid less than twenty-five cents per day for electricity. My nine year self was amazed by the blast of heated air I felt when my uncle demonstrated the way it all worked. Sadly, theirs was the only house I have ever seen in the USA with a solar chimney. I saw dozens of buildings with solar chimneys in Nepal and Bhutan, and it's a good bit colder there than most places in the continental USA.

Reverse cycle air conditioning has been the standard in Australia for a while now, but there is also a growing trend to using heat pumps for hot water systems over traditional gas burners or resistive electric heaters. Heat engines are just too good to not use for any heating or cooling applications these days.

I've been watching you videos for a while now, and I really appreciate all of the effort and expertise you put into them. You have a very broad minded way of presenting information to make it understandable by a good majority of people. I can tell by this video in particular that you truly care about our planet and would like to see some changes, and regardless of what critical comments come about regarding your opinions, I think it's important to acknowledge the deeper meaning of this video. So thank you for doing what you do, I love the videos you create. Please keep it going. You're making a difference.

I've been a fan of this channel for a while and I'm almost certain it's at least part of the reason I work for an HVAC company today despite having gone to school for biochemistry. I'm just an air duct cleaner right now, but the company I work for is gonna pay for me to get my NADCA certification so I can work on a broader range of issues and I just wanted to say thank you for making these concepts easy for me to understand, if only on a rudimentary level.

Earlier this winter I discovered that the central air conditioner in the house I moved into 2 years ago can be run in reverse as a heat pump. I literally would have had no idea were it not for your videos.

There's been some changes in legislation in Finland so you can build geothermal heatpump wells in a lot of places. With permission you can even drill the geothermal wells on city property instead of your own if it's not in the way of other infrastructure

When I first heard this thing in your video called a “heat pump”, I was so _pumped_! I immediately started to search this hidden gem that can heat my home more efficiently, and I realized…that’s what I have always been using. I was born in a eastern country and now living in another one and “heat pump” is almost the only form of “air conditioner” I know, and it’s definitely the most common one I see in every place I’ve lived in.

Can confirm. I live in Georgia (USA) and my parents' house has 3 heat pump units with a backup electric resistive heating element (that to my knowledge has only been used once - when the installers tested the system). My apartment also has a heat pump. It's smaller in size and on the older side, but it keeps me nice and toasty when the temps dip below 40 here. While I don't often get to air condition the outside (since my downstairs neighbor keeps their place hot year-round and the heat seeps up into my unit), I'm glad that the few times I do are more efficient than using other space heating techniques :) One of my coworkers was renovating his house and asked the HVAC installers for air conditioners. The installer refused and gave a few reasons to install a heat pump instead. He's been happier with it than he was with his old HVAC system with separate heating and cooling.

I have to say, the UKposts algorithm (and the release timing) on this video is impeccable. I just got an HVAC inspection on a house I am in the process of buying, and they are telling me that there are leaking coils and that the whole system will need to be replaced in the next year or two. They are giving me quotes for a like sized gas based furnace, but because of this video I am going to have to see if I can afford a heat pump instead. Great video!

When it was time for us to replace our old HVAC system, a gas/AC combo unit, I chose a heat pump in large part due to the information provided in your older videos. I thought you might want to know that your calls to action actually effect change.

Thank you for your informative heat pump video series. They have been most helpful as we were deciding to install mini split unit heat pumps in our Pacific Northwest home this past fall. While ours is not a high end unit good for colder temps, rather just standard base model, we have used the heat pump most of this winter. Supplemented with our older gas furnace only coldest days/nights, below freezing. We installed them for air conditioning but found the dual use most helpful as the natural gas market was changing during our installation.

Your enthusiasm for heat pumps warms my heart with a COP of at least 1.75 at 5 degrees F! That is one unofficial industry standard for what qualifies as a “Cold Climate ASHP”. I work for an electric utility in northern MN and part of my job involves trying to get customers to adopt ASHPs, particularly for customers with electric resistance heat. With over a million subscribers, you are literally doing my job better than I could ever hope to, haha. In addition to our own efforts, we help fund and work closely with the "Minnesota ASHP Collaborative" which is an organization that works to accelerate market adoption of Cold Climate ASHPs through research studies, contractor training, and homeowner education. In short, there are teams of people working to achieve the goals of this video, and on their behalf I say “thank you” for your support! Living in a region that usually occupies a few slots on most "Top 10 Coldest Cities in the US" lists, I can safely say that if it works here it will work anywhere. Most winters the Weather Channel sends someone to do a live report so the rest of the country can gawk at how unfathomably cold it is. We have made huge investments in testing and proving this technology because we do not want to promote something to our customers if there is a chance that it will fail them, and I can tell you that it works and works well. As you know, there is always a giant asterisk next to any claim involving homes, energy, and the personal preferences of these silly creatures we call “humans”, but assuming you have a competent HVAC contractor there is an ASHP solution for every home, even in northern MN where we expect nights below -20F and daytime highs under 0F for multiple days every winter. But of course, those days are the exception, and even here it is easy to meet 80% or more of a home’s annual heating load with an ASHP. Some additional resources you might find interesting: (Just search for these so I don't have to put in links) -Cold Climate Air Source Heat Pump Field Assessment (a CEE research study from 2017 with performance graphs at low temperatures and cost comparisons) -NEEP Product Listing - ASHP (NEEP provides a database of cold climate ASHP equipment with ratings at 5F and below.) -Minnesota ASHP Collaborative (some general info and case studies)

Canadian here, we installed a heat pump unit 2 years ago, and it give way enough heat output in the winter for most days. we do have a few days in a row that can be around -40, but we still have our resistive heating backup for those days. My parents were sceptical that it was really using less energy than the resistive heaters, and didn't know if it was really good to keep it working in winter, but I showed them the numbers, and they never asked again. Since more than 99% of the electricity where I am comes from renewables, I'm pretty happy about the negligeable carbone footprint we produce to keep warm.

Electric grid nerd here. There's still an unresolved issue with heat pumps in cold climates when it comes to backup resistance heat. The record low for Chicago is -25F, which would mean that everyone would need to use a ton of resistive heat in those very cold, albeit unusual, circumstances. The grid today unfortunately cannot support that level of usage by everyone without a major curtailment (read rolling blackouts). Folks who design, build, and operate the grid are in the exact business of "but sometimes" in order to try and get as close to 100% reliability as possible within the financial constraints set out by regulators. That's not to say heat pumps are bad or don't work or whatever. They do work and they *are* a good idea, even in Chicago. But to say that it won't require grid investments in terms of new generation or transmission or demand response is not quite accurate. The good news is that everyone *won't* be switching to heat pumps tomorrow, so it should be possible to do upgrades over an extended time period. I'm all in on heat pumps; currently have a heat pump water heater and headed towards HP heating in the next few years. I just know you're a stickler for accuracy and nuance, so I think this is an important point to discuss.

Howdy, Been following your channel for some time now and I really appreciate your level of detail in your videos and I would like to say that I enjoy your content immensely. With that being said, I recently went through a transformation with heating and cooling in my house. When I purchased the house it had a Hydronic heating system and a 10 seer trane air conditioner from 1999. While this was actually really efficient, it heated my house with the gas water heater that cost about 30 a month in the winter. I average a trend of 27KW a day in the summer of electrical usage. I went to upgrade, with cost in mind only switching to a heat pump and a normal gas water heater made financial sense. I will update when in the winter, but with the 14 seer heat pump I purchased, my energy usage in the peak (daily) of summer went from 27KW to 18KW. This is huge, I paid around 5200 for the heat pump and air handler combination, my gas usage is also down , but I can only measure that in dollars (around 4 dollars so far a month I will know more next month).

Since I'm getting quotes for heat pumps right now, this video was incredibly helpful in dealing with picking the right vendor, the right specs, and disproving the opinions of the installers, most of whom are telling me to keep my natural gas heat here in New England. Thank you!

At 1.8 k comments if you ever actually see this, we installed a mini split last year as our bedroom was at the end of the line for the central air and summers were toasty. Found ourselves using the heat function quite a bit this winter and barely firing up the furnace. Mind you we rarely see below freezing temperatures around here, so it worked out great. Your videos helped me understand what the mini-split heat pump is, and helped me decide to go ahead with it.

It's so crazy to watch this, I live in the southernmost state in Brazil and it gets quite cold (below 0ºC) in here and most of my life I thought that was how air conditioning worked, you can set it to cold or hot, it took me a while to discover that there are air conditioners that just cool, but the most shocking discovery to me when watching this series was to find out that it is actually more efficient to heat the air like this, I always thought it was an "undeveloped country" thing to heat spaces like this because it wasn't done like this in Europe and the US. BTW, our electrical system is mostly based on hydroelectric plants, but in months that don't rain too much we turn the thermoelectric plants on and get a "yellow" or "red" flag on our bill depending on how much non clean power we are getting (not only because it is more expensive to use coal but to discourage waste).

I am on the UK. Our government gives us £7500 towards getting a heat pump fitted. Energy company Octopus Energy fit them at cost. I will only have to contribute £3000. This price includes everything required including 12 new radiators. They will then at my request disconnect me from mains gas. I generate electricity from 16 solar panels and have a home storage battery. My very small contribution to reduce carbon dioxide levels. Loved the video and it is brilliant to put out this message worldwide although some countries are way ahead of us.

Love this video, the information and the engaging delivery. Thank you! Just on the verge of replacing my 12 year old gas furnace with an air source heat pump and electric air handler combo, subsidized under Canada's Greener Homes program. This video gives me even more confidence that I'm doing the right thing!

EXPERT HERE! I'm a factory technical representative for these and other HVAC items. Your video was exceptionally good and I'm sending the link to coworkers. There are some details missing, however, and they are important. That centers around sizing the system and defrosting. Without getting lengthy, the COP and HPSF ratings are for a condition that is very dynamic. I will simplify it that defrosting will occur in outdoor temperatures approximately 47 degrees, plus or minus. The need for how long the defrost and the frequency of it depends on both outdoor temperature AND the humidity. During defrost, the heat pump is now in cooling mode except the condenser fan is turned off. So, it is now removing heat from the conditioned space to melt the frost on the condensing unit coil! So, best efficiency is obtained in climates where the outdoor temperature is seldom below 47 degrees or so and defrosts don't occur. We have huge VRF systems where to not have defrost losses, the condensing unit is indoors, and gas heaters are used to keep the ambient warm enough to do so. In some cases, water source VRF systems are used and condensing gas boilers supply heat for the heat pump. In the summer, the cooling water is cooled through cooling towers on the roof. As to sizing the system. In Arizona, New Mexico, Florida, and the like, the cooling capacity needs are plenty for winter heating. However, in the north, heating needs can be two or more times the needs for cooling. So, while the heat pump may operate, it will require auxiliary heat. The rule for sizing a system is to size it for cooling needs. If sized for heating and that is larger than cooling needs, cooling performance WILL BE DISAPPOINTING! Mainly, temperature swings and very poor dehumidification control. Finally, Honda had an experimental home natural gas-powered fuel cell that was intended to provide the electrical needs of the home and charging an electric car. That seems to be a fascinating idea. I've not heard more about it. Have you?

Having now installed nearly 125 heat pumps, can say honestly they bring a new comfort level that my customers never imagined, with a lower monthly bill. (properly and optimally installed of course)

I found this channel through The Create Unknown and I’m highkey obsessed. This is content is scratching my exact itch as a pro-technology efficiency-conscious new homeowner. The first upgrade I made after moving in was a hybrid water heater and I LOVE the thing. It’s in the boiler room in the basement, so it performs just fine in the winter. But speaking of that boiler… yeesh, it’s an old oil boiler on its last legs and we’re gambling on it even making it through this winter, although so far so good. My family thinks I’m insane for wanting to switch to electric (for cost reasons in our area) but for environmental reasons I’d love to make it financially feasible for myself. I’d already been planning to talk to some HVAC profs about heat pump options in our area, but this video series is super helpful so I have a better picture of my options and how to talk about them.

Yes! More heat pumps America. Have you ever looked into the "Earthship" houses? They are amazing half buried passive solar heated, but they can also passively cool themselves via underground air passages. Would be interesting to see a Technology Connections point of view on them.

Hey just so you know, you're videos are in a special "always watch immediately" category for me. You're one of I think three channels like for me. Keep up the good work.

I’m in Georgia. And I had multiple HVAC techs tell me “Heat pumps don’t work below 40F”. Just made it through this winter with an inexpensive 14 SEER unit and a single 700w space heater without the house getting below 64 including a couple nights around 15F outside. A 19 SEER variable speed unit with 25% more capacity and we never would have noticed it was cold outside.

You do great presentations that are well thought about, thanks. For your next video I suggest that you also look at Mrcool DIY heat pumps. They overcome the main problem of connecting the refrigerant line sets by using prefilled refrigerant lines with their special connectors that just require 2 ranches to tighten. Currently Mcool DIY systems can go up to a 4 zones. I installed in my house two such systems with a 27,000 BTU 3 zone and 36,000 BTU 4 zone systems. I never installed any such system and 1st one is working great and heated my house in the winter at a fraction of the cost of oil heating. The 2nd one I will be finishing in the next week. Currently Mrcool are not the most efficient but are pretty good with SEER of 21.5 and HSPF 11 for the 36,000 BTU with 4 zones. For heating they work down to -13 F (-25 C) and for cooling up to 122 F (50 C) outside air temperature.

I have just install 3 mini splits in my home. They are working great in my living area which is Oklahoma City. We dont have too many days temperature goes down below zero, but whenever it comes to that extreme weather we have our old furnace system to be kicked in while I let those mini splits remain off until the normal temperature weather comes back. And that plan works flawlessly, I have no complaint at all. Even though my mini splits heat pump are not top tier quality units. Electric and Natural gas bills are the same with those years before I installed the mini splits system, but I save ton of money instead of install or repair the old HAVC system which come with expensive ductwork. The cost to install 3 mini splits system was about $2500, and I can install them myself without hiring a professional team which cost a lot more money. For the estimate to repair or replace my old HAVC system would be around 10 grands plus 2 grands of ductwork.

My 2 cents on the backup heating: Regardless of fuel source, you should ALWAYS have a backup heat source. Things break, and you don't want your only heat source breaking when it's 10 degrees outside.

I’m glad you mentioned the issue with gas leaks that arise because we’re piping it all over the place. I’d never thought of how heat pumps might be able to reduce that problem.

I'm always stunned by the amount of effort you put into research and then into creating the video. Your videos are really long, but not a single second is boring. Keep up the good work! 😎

Hi! I just discovered your channel today and have enjoyed 3 of your videos already. You are 100% right about heat pumps. I'm in London and am in my 12th year of my Mitsubishi Ecodan Air Source Heat Pump, the only area I would pick you up on is that a modern Combined Cycle Gas power plant, as used in the UK, is actually about 60% efficient. In the UK an ASHP over the year averages at a claimed COP of about 3.5. Our lowest temperatures in London are about -5C. My ASHP drives an underfloor wet system, so probably achieves in excess of the claimed COP of 3.5 as the flow temperature is low and inversely proportional to the outside temperate. It heats the hot water too on a high temperature hot water cycle. Solar thermal provides hot water for about 8 months of the year. For heating swimming pools (in the summer) COPs of 5.5 are easily achieved so make massive sense. Cost wise I have a Tesla PowerWall and currently pay 11.1p/kWh for electricity (24x7) plus 20p/day standing charge. That's a special deal as Tesla export the energy from the PowerWall at peak times and charge it from my solar and also on off-peak electricity. As a comparison mains gas would cost about 9p/kWh plus standing charge plus safety maintenance at today's inflated prices and as you say a boiler is about 90% efficient, so an ASHP is much cheaper to run on this tariff. Installation costs are not that different for a new build house, especially when you consider you don't have to pay to have the gas main run to the house. That's exactly what I did at my house.

Great video, I'm from the Netherlands where there's a big push for so-called hybrid heat pumps at the moment. They're installed as an add-on to a gas furnace, and are designed to take care of heating 90-98% of the time. Only when it gets really cold (which to be honest, is nothing like Chicago) the gas furnace adds the extra heating power required. I think it makes a lot of sense to widely adopt these, since the electric grid will not be pushed to its limit or needs to be updated for just a couple of hours each winter

I put in one of these Mitsubishi units last month and thought I was reading something wrong in the manual concerning its heating effeciency at -15f. It really is quiet, efficient and most importantly effective at what it does.

This is such a great informative video! We are fully decommissioning oil heat in our New York house and installing two hyper heat ducted Mitsubishi heat pumps. I'm a little anxious to see them perform next winter, but I am pretty excited overall!

Thanks for a really nice video! You should also look into Air Heat Exchangers. Up here in Scandinavia the most common heating installation in newbuilt houses in the last years has become a combination of Air Heat Pumps and Air Heat Exchangers to minimize the loses when ventilating the house.

I found this video very interesting because all of the places that I've lived in for the past 22 years have always been heated with a heat pump. Literally all of my life. From my experience they just work all of the time without fail and that makes the lack of use of heat pumps in the US very intriguing to me.

It would be cool if you could do a segment on the current refrigerants. CFCs are banned, HCFCs mostly phased out, would be cool to see a good dive into why those are banned/phased out and what currently available ones have taken their place and how they compare.

I installed a mini-split heat pump system in my office last year. It worked great in the summer, cooling during the 95F days. This winter, we had a few nights of 0F, and the heating kept working but ran more often. I do keep it warmer when cooling and cooler when heating. The propane price was already high, and we had to get more middle winter as we are figuring out the new places. That was not a nice bill. Only a few winter fill-ups and I can pay for the main house getting AC and Heat Pump installed. Paired with solar at some point, I cant see keeping propane as our only heat source. One note, last I had heard from guys in the power plant industry, the new GE turbines claim 30-64% efficiency not sure if that was with heat recovery steam generator (HRSG), I know one project I worked on it was more efficient to create electricity to run motors with HRSG than to direct drive the systems using natural gas. It's also too bad we are scared of old nuclear technology and not the new fail-safe high efficient nuclear steam power generators. The new ones are small self-contained systems that can be deployed locally for power use and have a life span of up to 100 years.

Thank you for the very informative video. I live in the Seattle are. Bought a house in 2014 that was built in 1987. Replaced the original gas furnace with a heat pump and high efficiency backup gas furnace. Replaced old gas hot water tank with gas on demand hot water. Replaced all incandescent lights with LED. Installed an 8 kilowatt PV grid tied system on the roof. Replaced two gasoline powered cars with two Tesla BEV’s that charge 95% at home. Added extra insulation in the attic. Even with gray, rainy Seattle weather our PV system generates over 60% of our annual electricity usage. Our natural gas company has sent status report emails stating that our gas usage is only 20% of their average customer. It seems like our experience aligns with your video’s content.

I've got an extremely efficient Australian-made (ActronAir) heat pump ("reverse cycle" ducted refrigerated HVAC) AND rooftop solar at my place. It's absolutely fantastic.

I want to add heat storage to the backup solutions. A big water tank can store enough energy to get you through those cold days and doesn't really cost anything. It also means that the heat pump can run indepentently from the heat demand. That way it can get around peak demand times with high prices and high grid load.

I love you brother. I always love to see you get nerdy on interesting topics! You've had a place in my mind, and my heart, for a few years or more!

Your last couple videos have convinced me to switch to a heat pump from my ancient boiler/baseboard heating system instead of replacing the boiler with a modern one. So far I'm loving the multi-zone mini-split heat pump system.

Thank you for doing this update. Because of your previous heat pump videos, I was set on only getting a ground source heat pump, but they are prohibitively expensive to install here (in Scotland). Watching this has me willing to start crunching the numbers on air source, as I'm desperate to not have to get another boiler. I'm looking forward to the install video.

2 things. 1. I just found your videos, and have been watching the heatpump section. I found your dishwasher stories, and watched all of those first. Anyway, I have enjoyed watching your hair grow. Thats all on that point. 2. The more useful thing, is that I have come here for a solution on cheaper cooling, and was surprised to hear most people are concerned about heating costs, as, in Ohio, my heating costs are nominal.

Well never thought I’d have watched the whole video. But I stayed and it’s great. I’m looking at heat pumps and the scop has surprised me. Thanks for the info. Looking for the other videos in the series now

Nice video! I live in Sweden and even though we have quite cold winters all types of heat pumps are very common here and so are roof top solar, I think that is a winning combination.

18:10 Thank you, I like this point a lot. Most homes already have no backup heat source, so why is that only now an issue? With the extra efficiency of heat pumps on all other days, having to bust out the space heaters a few times isn't a big deal. And like you mentioned, tons of places will never face this obstacle. I live in Georgia, and even basic heat pumps will work year round.

Your videos are amazing. I started with the dishwasher/detergent video and never stopped.

My dad is the business development director at one of the largest industrial heat pump companies in the world (remaining nameless for anonymity). He is working with multiple cities and companies, mainly in Europe, right now as they ever increasingly realize this fact. Especially Germany.

The heat pump in my all-electric house (dated 2006, since that's when my house was built) has resistive heating elements (heat strips, like you said) in the indoor part of the system, in case it gets too cold for the heat-pump to generate enough heat. You can definitely tell when those things kick on -- our electric bill goes up by a good 25% or more in those months. It's amazing to me that these new heat pumps can still draw heat from the outside air even when the temperature is only 5 degrees F. That's a relatively recent development, I'd imagine? My 16-year-old heat pump definitely cannot do that. If it drops below about 28 to 30 F those heat strips kick on (the thermostat has an "Emergency Heat" indicator when they do, so you can easily tell). But I live in northern Georgia, so it's pretty rare that we drop below freezing at all, let alone below 28 or even 30 F. We might spend a grand total of 14 nights a year with temps that low, and maybe 5 or 6 where it stays below freezing for 24 hours in a row? When this system craps out (hopefully not *too* soon, but these things usually don't last more than 20 years, so it's gotta be in the not *too* distant future, I'd imagine) I'm definitely going to pay attention to the COP rating of the new one we'll be buying. I'd bet we could get one that wouldn't even need resistive "emergency" heat -- dropping down to 5 F in this neck of the woods? Unheard of. (I just Googled it. I was born in April of 1970, and since then there have been four -- FOUR -- times that the temperature has dropped below 5 F here, and the most recent one was way back in 1985. LOL I think we could put out a few space heaters for a few hours on those days, if something like that ever happens again.)

Italy has apparently had a successful heat pump replacement program where the government payed 110% of the installation so there was a bit left over for the homeowner. There's always corruption and stuff in Italy related to things but this but it has still improved Italy's GDP and made it more environmentally friendly

I found your channel pretty recently, and I've been impressed by how good you are at explaining the things I've seen you cover. You got my subscription when you dared to say the words "heat pumpdate", though. Nicely done.

Looking forward to your next video on this subject. Your timing is impeccable!

4:40 The absolutely best way to use that gas would be to use it in a combined heat and power plant. In that case you'd have 40% as electricity and another maybe 40% as district heating (for hot water and heating in winter), if people outside the range of the district heating network used heatpumps you'd get about as an efficient system as is possible.

Worth pointing out that even in cold environments where a heat pump can have issues, those issues can be mitigated by pulling air through a ground loop. Most places that experience ambient temperatures below what a heat pump can operate with have ground temperatures that are reliably above 40F year round available a mere few feet down into the soil.

I put a PTAC with a heat pump in my 700sqf home. I live in the south now, so it doesn't get too cold, but have a resistive heater/ac to take up slack in cold/heat snaps. It keeps my pipes from freezing, and keeps me warm for a fairly cheap price. Purely electric home and diesel backup generator for power outages. Converted the propane tank to a diesel storage tank as well.

I'm a heat pumper in the Chicago area, too. It's a superb experience. For the very cold days I use a few space heaters and they totally do the job. My house is well insulated -- you can get various rebates for improving your insulation, making it much more affordable than you might think.

Heat Pumps have been widely used for heating in Europe for as long as I remember. One of the main selling points here, that was worth mentioning, is that they can be used for both - cooling and heating, (hence known as just Air Conditioners here) and thus saving you a lot from having to install two separate systems, especially on new buildings. Having had (and still have) both - AC and gas fired radiator based heating I must admit that radiators bring much more comfort than air conditioners do, however, although more expensive to do, heat pumps can be used to heat water and than respectively radiators for much more comfortable conventional heating.

I've already switched, couldn't be happier. Got Toshiba penta splits inverter. Very cheap, and VERY efficient. My home is 3 floor around 200 meters square, with 10cm styrofoam isolation, and temperatures reached -10 degrees Celsius where I live on several occasions. In two years Inverter didn't suffer much. It inverts the cycle for about 10 minutes to defrost itself in like every 3 hours or so.

I just replaced my natural gas furnace with a heat pump. Washington State has the third lowest price on electricity in the US, so it made sense to. I wanted to add on a central A/C for the summers, because I hate when it gets above 75 in my house, but due to the tight space where the existing furnace was, it was easier to fit in a new heat pump and add in a compact electric furnace as a backup. Our natural gas has also been pretty cheap, so I haven't seen much difference in heating costs from the year before, but I'm still happy with my purchase. I think I'll be even happier when summer hits and I don't have to worry about using window A/C units anymore :).

New to the channel and loving the videos. Please never stop making them.

I'm considering getting a heat pump for my house now after seeing this. Don't forget about electric blankets as an alternate heat source. I feel they are more efficient than a space heater as it doesn't need to heat an entire room/house for the heat to be effective at providing heat to us. Also I just heard at work yesterday that Tesla uses heat pumps in their vehicles, which now after your explanations makes a lot more sense.

Wow, what timing. My family got our heat pump installation finished literally yesterday, after years of deliberation because we struggled to find a good contractor. I can already say it was a worthwhile investment, as we no longer have to keep several portable resistive space heaters running basically 24/7 to stay warm.

I installed a mini-split AC/Heat pump in my house up here in northern MN last spring. The AC was great when we needed it in the summer. Then as it got cool we flipped the unit to heat mode. We ran it from September until the snows finally arrived in mid December. Saved us about 2 LP tanks worth of heating fuel over the winter. (roughly 1000 gallons) When we put up our garage I think we will be using at least one of these new units to heat that building. (in addition to a larger earth-buried line system)

Air pump haver here in the midatlantic area. My hvac system was nearly state of the art when it was installed in 2017. I live in a trailer with not so great insulation… my auxiliary pump comes on when the temp gets down around 15 degrees outside. This happens infrequently. I’m very happy with my heat pump.

Roughly 50 years ago, my parent's friends had a natural gas powered heat pump in their Midwest 4500 square foot house. In summer they kept their house very cold, in winter it was toasty warm. Their utility bills were much smaller than our 1900 square foot house.

In my experience the ambient temperature around the external units of heat pumps can become much colder than the reported general air temperature especially if there isn’t much wind. So the efficiency can tank as they are operating in lower temperatures than expected. So placement of the external units is pretty important but often they are just put in the most convenient place for the installers.

Your videos are the reason my new home is built around a heat pump. Thanks!

I gave this my 👍 after you said “heat pumpdate.” Then I watched the rest of the video. Great stuff! One challenge I wish you had touched upon though (maybe you do in the next video) is the need in many places of the world to upgrade the strength of our electric grid and electricity generation capacity. Without question, heat pumps are the most efficient way to heat our buildings from any form of energy, but having everyone use heat pumps in the future will specifically increase our electrical energy demand, especially on those colder days. This means, we need to invest in *MORE* wind energy (more turning, more now) and solar energy (more sunning, more now) and energy storage (more storing, more now) for this future to produce that electricity safely and reliably, and we need to invest in upgrading our electric grid so we can deliver that electricity to our buildings safely and reliably.

I moved into a new place (northern US, we get plenty of snow here) most of a year ago, and was surprised, given the climate, to find the central heating was an air-source heat pump. I haven't had the slightest issue with it, though. Things have clearly improved since my knowledge on heat pumps was gained.

Thank you so much for bringing this to our attention. I live in a place that doesn't often get below 15C (59F) in the winter time but in those times having heating would be nice. Next time we upgrade our AC units we will get one with a heat pump function.

Great video, and agree 100%. Modern heat pumps are fantastic. One thing to note: air sealing and proper insulation is HUGE in how much energy a given house/building/space takes to heat and cool. Even a brand-new house is pathetic if simply "built to code". Older houses are pretty bad. We KNOW HOW to make very efficient buildings, and we know how to retrofit existing buildings to become more efficient. IMHO, doing so needs to be part of the solution. Combined with the magic of heat pumps, it is a double-whammy in energy savings. Perhaps a topic for a future video? Dig into it a bit, you'd be surprised to learn there are some builders currently making homes for the same cost as a "normal" home that use a fraction of the energy. A nice side bonus of these homes is they are nice and quiet inside (outside noises stay outside) and also really comfortable since there are no drafts.

Awesome video! The 2.5 COP to match gas is actually even lower when you factor in leaks piping gas to your house. Exact on these leaks is hard to come by though so I accept that you just noted it. In your install video I hope you get one of those crazy cheap 15 HSPF 9,000BTU Gree units and at least mention the new window mounted heat pump that Gradient is about to release (it will truly be the easiest to install heat pump ever).

I've been pumped for a return to this heated topic for a while.

You hit on this a little bit in the video, but the "but sometimes" factor of this problem is a bit harder to find a solution for, in that when it's extremely cold, everyone will need their backup heat all at the same time. If the backup heat is electric, then we find ourselves in a situation where the grid needs to be able to support everyone in the area using resistive electric heat all at once, which would be very wasteful to build out when it will be used only in the rare extreme cases. The alternative option would be for the backup heat to be a gas furnace, but, as you mentioned too, this could introduce an added cost to families that will make them not want to go that route. Many utilities have a minimum that they will charge even for zero usage, so families would have to pay to keep a gas line active that they will only need a few days of the year. If there's no such fee in someone's area and the cost for zero usage is indeed zero, I think a gas furnace as the backup heat makes a lot more sense than resistive electric for the foreseeable future. True, resistive electric can become more "green" down the road, but realistically we aren't getting there before the next time that furnace will need replaced, so locally burned gas is still a better solution than purely resistive electric heat strips. Some kind of fossil fuel stored locally in a tank onsite could be an interesting solution, but transporting fossil fuels by truck is so laughably inefficient that we'd be wiping away a non-negligible chunk of the environmental benefits just accounting for the edge cases. But, that would be an easy transition at least in many rural communities where locally stored propane, oil, or some other fuel is a common means of home heating already. You could do a similar thing with something akin to Tesla's powerwall for homes with electric backup heat, but I'm not sure that manufacturing lithium batteries of that size and quantity to account for an edge case is a great idea. There's also the defrost cycle time that will require the backup heat, but the "but sometimes" factor isn't nearly as great there as it's very unlikely that a large percentage of homes will all be in defrost mode at the same time. All that said, and recognizing that heat pumps aren't without problems that we have to figure out how to solve, I still think there's very little reason not to have a heat pump installed next time anyone gets a new AC system, especially if the backup system is something that is appropriate for the infrastructure in their area. They *shoudn't* be significantly more expensive than an air conditioner. They often are, but that's an artificial markup. If everyone understood that heat pumps are just normal air conditioners with a reversing valve, it would be harder for manufacturers to inflate the price of a machine that does both.

I have a 120V window heat pump made by Friedrich (the Kuhl model) and LOVE it! Window heat pumps look like an A.C. but can go in reverse. It’s not as powerful or efficient as a ductless mini-split; but all the mini-splits have to be hard-wired to your breaker box whereas a window heat pump just plugs into an outlet. Window heat pumps are pretty rare though. Amana makes a 240V window heat pump and that’s the only other once I found. Friedrich makes literally the only 120V window heat pump on the market. They say it heats when the outside is as cold as 37 degrees F, which is pretty rare for where I live (Los Angeles). It’s kept me warm in in the winter and cool even during brutal heat waves.

@technology connections; It's always good to hear someone understands thermodynamics.

The mention of good insulation is important, and I'm glad you did. My current apartment is brand new and came with a heat pump and what I can only assume is an electric backup heater. Been living here since mid-January in western Virginia, and not once has the backup heat come on. We've had some pretty cold days where two or three time it was almost zero, and still nothing. My apartment is very well-insulated, and that's helped a heck of a lot. Over the past week (currently late March) my heat has barely been running outside of a couple cold days. The normal temperature here and the apartment's insulation mean that the heat pump is crazy efficient right now. These sort of temperatures are fairly steady for the spring before it gets hot. A good heat pump and good insulation work wonders for a small living space.

I had a 48,000 BTU ductless min-split system installed August 2021 in my old, drafty New England house. Air conditioning benefits aside in the summer, I was particularly interested in heating. Previously I was typically going through one tank of oil every 5-6 weeks running November to March (about 5 months), depending on how cold. This translated to 5-6 tanks per season, which at $500 or so per tank, translated to $3,000 or so spent on oil per year heating. Over the same period of time this year, with my heat pump I was able to cut my oil to just about 1.5 tanks, or about $800 spent on oil. That's $2,200 saved on oil. Over the same period, my electric bill went up about $175/month, or $1050. Net savings $1,150. With a savings of $1050 and a finance plan of $170/month, that means at an "average" monthly savings ($1050/12 = ~$87.50) the oil savings alone are paying for about half the system. Not bad, and I'm thrilled with summer AC (functionally central AC) and the reduction in oil burn. Love my system.

Yey! Excited for part 3 :) thanks for putting this stuff out there as it's helping lots of people, myself included!!

0:23 Thank you for saying this. Also, thank you with continuing to examine this topic.

Lets hope that increased demand and volume of sales for heat pumps has the effect of reducing price and further increasing efficiency. Great video, and yes, this viewpoint needed to be emphasized. See you on the next one. Cheers.

Because of your video, I recommended my parents get a heat pump for a project. It can keep a large space at room temperature down to -25 Celsius outside because it's so dry in our climate that there's little moisture in the air to freeze onto the condenser

I would be interested to know how much overconsumption is due to the fact that people with heat pumps can now access to A/C in summer while previously they didn't. It's a confort increase for sure but also an energy consumption increase compared to furnace. Nice video for engineers as always!

I just installed an inverter heat pump/ cooling system in my living space and it's amazing, barely needs to run and hardly consumes any power when it does. What especially helps is full insulation with Low E windows.... Big difference over old single pane windows.

I bought a heat pump dryer based on your previous heat pump videos. I love it. Sure, it takes a little longer to dry stuff but it uses a ton less electricity (measured with an energy monitor.) Thanks for converting me.

We've been very happy with our inverter heat pump system. It was more expensive than a traditional one- or two-stage heat pump system, but our A/C bills dropped to zero and our heating bills are about 50% of what they were when the temperatures drop under 40F. My only complaint so far is that when it gets really cold, like

Your recommendations are so good you should be hired to inform public policy makers. You could also share affiliate links to allows us to give you a percentage of the things we buy. I bought some things you recommended. The can opener is unbelievable

Those backup heating elements in ducted units are usually called emergency heat or e-heat on your thermostat. Our AC unit did quit working for about a day during that polar vortex and that saved us. Like he said though, their COP is only one, so expect your heating bill to adjust accordingly if needed for long stretches. Having a heat pump did definitely drop our heating costs in the winter overall.

Hey man. Good video. I do appreciate how reserved you were when you presented opinions, and you did really well in differentiating them from the ideas you meant to talk about. I think that's what you were going for, so keep up this path if that's where you're going.

I love you promotion of heat pumps. I would love to see you look into "extreme" insulation of homes. I have seen home insulated on the outside. Like some sort of blanket. I do believe that higher insulation and heat pumps can really reduce energy use and save money as a bonus.

This was one of the first videos I watched of yours, and you'reoneofthefew channels I actually have notifications for. And now I'm back here because I'm taking a physics course where we're learning about heat pumps, and this is the first place I ever heard of them. I'm not even going into a physics related field. Funny how the world goes round

Heat pumps are amazing, I can tell you they are widely being adopted in the State of Maine and they work through our winters. Cheers, guys.