Hey everyone, it’s pinned comment time! And there are some *corrections and clarifications* here. Exciting! First, heat pumps part 1: ukposts.info/have/v-deo/b3pmZqN7oZCr1aM.html Second, refrigerants! Sloppy script-writing me didn’t catch that I implied CO2 as a refrigerant was the _only_ other option, but it’s not! There have been many climate-friendly refrigerants in use in lots of applications such as isobutane and propane, but the main trouble with these is they go boom sometimes. In larger systems the quantities needed can be dangerous which is why R-1234yf and CO2 as refrigerants are important! Third, heat pump dryers! My explanation into them is, um, well not right. It’s better to think of them as giant dehumidifiers that recirculate air through the drum. Heat slowly builds up, but it’s not really being taken from the room. Instead it’s just the heat created by the compressor being continually recaptured, and a sort of thermal feedback loop forms. The cold surface of the evaporator also pulls the moisture out to be collected. Here’s a video from This Old House that has a great diagram (though the refrigeration cycle’s magicalness of latent heat is pretty much skipped) ukposts.info/have/v-deo/fJV_YZ5tpqamxoE.html Fourth, I regret saying it's a "myth" that tankless heaters provide instant hot water. More fairly I think it's a misconception. Fifth, I dunno! I’ll add stuff here as we go along. Aren’t pinned comments neat? I love being able to put information right up at the very top for you so you don’t have to waste your time commenting!

As a HVACR technician of 27 years, I just want to slap you....on the back and say bravo, and thank you for this extremely well made video. Information that I have been preaching for years.

Me mentally constructing a perfect home with all of this technology

When I was in HS in the '70s my girlfriend's father "invented" his own geo-based heat pump system. It almost worked! The first time he fired it all up something was obviously not entirely correct because he ended up freezing his lawn solid! A few modifications later and it actually pretty much worked, enough so that they had heat and A/C that actually kept the house pretty comfortable. Not bad for a shipyard welder with no formal HVAC training.

Hi I'm very late to comment on this video but my FAVORITE use for the heat pump is the combination ice rink/swimming pool building. Western Michigan University has both of them in the same building and the majority of the heat for the pool comes from cooling the ice rink, and I imagine there is a huge industrial heat pump in the building managing both. I just thought it would be nice to share :)

When I was about 9 we moved into a new home that my dad had designed, built by a local contractor. The primary heating system he had put in was geothermal. The secondary system was an advanced wood furnace. It was able to burn various types of woods at the correct temperature to avoid releasing any harmful particles or gasses. The furnace was only meant as a backup, in case we were to endure any particularly cold winter months and needed any additional hot water. - You see, my father and his 3 brothers had, a little over a decade earlier, taken over the family business, a small company producing looms, workbenches, and conference furniture out of wood. So during wintertime, he would keep a small stockpile of wooden leftovers in case we needed to feed the furnace. - I did obviously get the full story and explanation (several times actually) along with instructions on how to correctly adjust the furnace for the different types of wood. But as a kid, I didn't really think much of it and thought it to be fairly common. It wasn't until much later that I was able to grasp, how far ahead of his time my dad must have been by choosing a geothermal heating system... because the year we moved into that house was 1980.

0:27 I like to imagine that Alec spent a large portion of editing time browsing through stock-video sites to find a pair of roof AC units that were explicitly _not_ lined up with each other, or with the rest of the building.

As a professional HVAC service tech, I have to say your videos are absolutely on point even down to the terminology (despite missing accumulators but that's perhaps beyond the scope) but even after about a decade in the field this has been an incredible refresher and I will absolutely be referring future apprentices under my tutelage to these videos.

I think it isn't enough said by your audience, since most porbably the majority of them are in US. BUT THANK YOU A LOT for converting all the temperatures in Celcius, it helps A LOT for me and all people who watch you outside from US! TNX!

26:29 "We've talked about all I wanted to talk about heat pumps" I have trouble believing that.

01:27 - The most cinematic shot of any non-Nest thermostat on video.

Thank you for a detailed information about geothermal heating! Our housing cooperative in Finland just finished drilling 42 holes, totalling more than 10 kilometres into the ground to switch from district heating to geothermal heating. We have 138 flats and 9 buildings. We also installed 250 kWp solar panels. At least so far electricity is cheap and fossil fuels very expensive here. Every heating system is required to operate at -29 °C (-20°F) here.

We are a geothermal heat user since 1992. Amazing units. Also makes our hot water (most of it) and in the summer said hot water is FREE (as in beer) because it is the first place the excess heat from our home is dumped. The heat pump is completely inside the home and the same size as a standard furnace. It's also just as quiet, literally the only thing you can hear is the fan. Here in Western Michigan USA the electric backup heaters have almost never been used. Highly recommended!

Hi! Guy from Finland here. Ground heat pumps have been extremely popular here in the last 15 years. Mostly installed in detached houses and small housing associations.

An alternative take on "You don't hate your heat pump, you hate your thermostat" would be "You don't hate your heat pump, you hate the guy who installed it" If your heat pump seems to break all the time (like several times in one winter) get a different company than the installer to check it.

My parents had an underground (drilled) heat pump installed fifteen years ago. It more than paid for itself within 8 years. Now it's just gravy and massively improves their property value. Also cities are often near lakes or oceans, which can be used as a huge heat pump resevoir. Look at what they did in downtown Toronto.

"Carbon dioxide can actually be used as a refrigerant... Although when you do that, it prefers if you call it R744. It's more polite." I love you 🤣

I had a friend who once hooked up their heat pump to their swimming pool during the summer to use as a radiator and it heated the pool and cooled the house. Why don’t we see more setups like this????

The Heat Pump Manufacturer's Guild should really be sponsoring your videos, because I'm sold.

“Turn around, there’s a thing there that can be found! A human skull on the ground!” - Turn Around by They Might be Giants! I’m amazed they are still making albums, they have like 30 already. I wonder if we can get them to make a song about heat pumps.

I know this is an older video, but I figured i'd input my perspective as an automotive technician. Heat pumps are amazing, as you point out with a bit of comedy. For housing, heat pumps make great sense and I never knew there were heat pump water heaters. I want one. As far as automotive goes, why more cars don't use reversible heat pumps, it's nothing to do with reliability. The switching valve is incredibly robust and not prone to damage from vibration, at least not more than the compressors themselves. The main issue with it is complexity. You can't just stick a reversing valve in, when you select heat you then by design lose AC. This means no dehumidification of the air, which makes defrosters far less efficient and also serves to humidify the car. The solution is to install two evaporators or a split row evaporator, one stays AC always and the other can be switched between heat or AC. The method of doing so would require switching the heat/ac section between the condenser or evaporator lines, this is the only way to make such a thing work without even more needless complexity. Since you always need once AC section of the evaporator, you must always have a condenser. This limits the condenser behind the grille of the car to only being a condenser, it can never be the evaporator (or you lose AC and just the two sections in the cabin air box will result in a net zero change in air temp, one cools and the other raises the temp both by the same amount). So the only option is to switch the heat/ac section of the cabin airbox evaporator between the condenser side and the evaporator side. This would result in hot dry air so long as you routed the discharge line to the cabin air box first then to the main condenser. The problem is complexity, now you have not just one evaporator you have two (they can be the same physically assembly but the plumbing must be separate) which means twice the refrigerant lines in the engine bay from the reversing valve which also must be right after the compressor. It means twice the thermal expansion valves, and twice the pressure sensors. All this in an already tight packed space with hardly any room. It could be done, but the complexity just isn't worth the slight energy savings. Especially considering you could just use waste heat from the batteries (if they are producing enough that is) to supplement the electric heater. I love your videos, i'm not trying to nit pick I just wanted to give my input as a professional in the field.

The quiet, "usually" after, 'you know how pipes don't freeze underground' is hilarious

I live in an 8 apartment building in Sweden that gets its heat from refrigerant-to-liquid geothermal. We installed it just a few years back so we could throw out the old oil furnace. The unit itself in the basement is really quiet, it saved us huge amounts on heating costs and has been way more reliable. 10/10 would recommend if you can get past the high upfront costs.

I used to rent an office space that had what we call a "heating AC", now I realize it's one of those that are reversible. We used it as little as possible because we thought it would consume way a lot of energy, now I see that I was wrong!

My town actually does district heating from trash incineration, and the town one over does it from fermentation in a sewage treatment plant. There really is an exciting number of options beyond just yeeting mains voltage across a resistor.

"One thing's for sure about the future: I'm pumped for it!" How dare you.

The April Fool's joke in this video is that it's a straight video on the April 1st.

Chiming in from Germany here - we bought a clothes dryer with a heat pump some years ago, use it a lot - A full load on the normal setting runs for about 2 hours on a 400W energy intake - totally fine on a 16A fuse together with the washer (230V system, 2500W washer). A cycle of drying clothes (in the max setting) is about 1kWh. Compared to the old one that was using an electric heater, thats less than a third of the energy. The old dryer averaged 1500W for about 2.5hrs, did raise the room humidity significantly and needed a separate circuit from the washer - or a tighter schedule. We’re very happy that we decided to go and buy that new one, because it wasn’t even that expensive. I don’t know about pricing in the US, but this brand one set us back about 700$ (converted) in 2018. Thanks for pointing out more ways to use heat pumps :).

Funny note about dryers. In my last home (decades ago), the dryer was in the garage, which shared a wall with our livingroom. My husband installed a way to move the vent tube to a hole in the wall in the winter so we could use that warm air, lowering our natural gas bill with heat we were just venting out to the environment previously. (In warm weather the hole was closed and the vent went back to the outside.) This _literally_ saved us when the gas heater broke during a snow event. Yes, running the dryer was expensive but it kept our home (and us) from literally freezing, and the cost to run the dryer for 1.5 days was waaaay cheaper than what the repair company would've charged us for an emergency visit during a snow storm. The house was a 3 bedroom single level but on the smallish side, built in the 40s, so it wasn't like we were trying to heat one of those modern multilevels.

So living in europe i am amazed at how many of the things you describe has been everywhere for over 15 years.

That "TOO DEEP" alert legitimately cracked me up every time.

As a HVAC tech in Australia I love how much you know about the switching of a reversing valve. I love it’s brutality 😅

I live in the southern hemisphere, and I'm glad this series of videos was made facing our winter.

All of these problems become really interesting in the subtropics (most of Australia, Florida etc). You want hot water for your shower but you want air conditioning to cool your house. So an 800w heat pump hot water unit is sitting outside your house chilling the air and heating your water, while an 800w air conditioner is sitting in your bedroom chilling the air and heating the air outside. We need central AC systems with central water heating built in.

Few feelings are more uplifting than staying until the credits and watching Alec's fall from the pedestal of extremely eloquent and well-spoken content creator to a mumbling bumbling everyday person like the rest of us. Thanks for leaving in the blooper reels!

I have a friend with geothermal heat pump on pond loop and ground loop I changed out this year that he ran for more than 30 years with minimal maintenance thumbs up to you imparting KNOWLEDGE to others

Welp, I’ve been skipping a bunch of these videos over the past couple years and boy was this a series I needed. I live in an addition in a home that has always gotten freezing in the winter and boiling in the summer. Two years ago I got a mini split, and I’ve only ever used it frequently as a air conditioner, because I was convinced by an uneducated person that my carbon footprint would be terribly increased by using it instead of gas heating. Now I plan to run it whenever it’s above 35 degrees f. I already loved how effective and quiet this thing is, now I can feel less guilty about it. I also will tell all my solar powered friends that they should absolutely be using that excess power for heat. Also, it makes me kinda incensed how my very green city and neighborhood hasn’t been pushing heat pumps or geothermal at all, but have all sorts of “environmental” initiatives that are way more expensive and way less effective. This is going to become my new soap box.

The "heatpumps don't work on the coldest winter days" argument is the same as "how do I transport all my construction tools/furniture/etc on a bike" argument. Yes, heatpumps and bicycles might not work in every single circumstance, but they're greatly beneficial for the vast majority of circumstances in which they do work.

This video reminded me of the casual comment my professor said 20 seconds into day one of my heat transfer class: "Life is a heat transfer problem."

(Canada) My home is 2900 ft² two stories and I've been using a heat-pump since 1995. My first pump ran 24/7 for over 20 years, before finally failing. (R-22 refrigerant) My replacement pump (R-104 ?) now does the work. Over 25 years the annual heating cost has been ±37% savings and summer air conditioning to boot ! The room winter heating temperatures are even through out the house. I've used oil furnace as back up but will be changing to an electric furnace some time this year. Had I been smarter back in 1995 I would have gone with the geothermal pump (I have a large property) but that isn't the case. Heat pumps are great ! Always enjoy your videos ! Thanks.

I am a self-taught refrigeration system designer (Thank you internet!) and I would like to suggest that the reason heat pumps lose efficiency when the outdoor air gets colder is not because there is a lot less heat in the air, the difference between 70f and absolute zero vs the difference between -20F and absolute zero is quite small after all. It is because in the summer we are moving heat from a space that is 70F to a space that is 100F, a difference of 30 degrees. In the winter we are moving heat from a space that is -20F to a space that is 70F, this is a difference of 90 degrees. The efficiency of the compressor (COP) is directly correlated to the pressure increase it needs to produce. The pressure increase correlated to a 90F rise is WAY, WAY, more than the pressure increase correlated to a 20F to 30F. If you want to know the COP potential of a refrigeration system, look at the required temperature DIFFERENCE between the evaporator and the condenser, not so much the actual temperatures.

I got a lot more enjoyment out of that "They Might be Giants" reference than you can know.

When you got to the geothermal section, i thought, "wait a second, i already have a hold drilled a few hundred feet down... My well!" Yeah, turns out there are geothermal systems on the market that can use well water for their constant temperature source. Neat.

With thanks to your videos, I replaced my AC with a heat pump, leaving my propane heat as a backup. And that could not have been better timing given fuel prices.

I just had a split system (tap water heater plus circulation water heating) air heat pump and it's working splendidly. We've had temperatures down to -20 already this winter and it's kept my 130+ square meter living space warm 20°C. Plus my garage/full cellar at about +13°C. COP has been about 2.5 on average. This in southern Finland, we do get really cold days but not usually very many in a row. I'm planning to build a big solar heater on the southern side of the building, to heat up the cellar. I believe that's where the biggest loss of heat is, currently.

"I'm pumped for it." I love that face when he said that.

I was blown away how little heat pump cloth dryers actually cost to operate. It always felt luxury to me to have one, but recently I needed it because of the high humidity from drying clothes. And yeah, you can literally operate it from any outlet. Mine is temporarily in an unused sleeping room and works very well. Incredible how much water it collects from a load, and just thinking about all the water previously was getting onto the walls.

My dad's a big energy efficiency nut like you. We've had an air source heat pump (that you will be delighted to hear, also works to cool the air all in the same unit!) for years now. We also had a hybrid water heater for years, but the refrigeration section broke and my dad didn't bother to fix it because it made the already cool basement truly frigid. He WANTED to get a ground source heat pump. Unfortunately, regulations prevented him from doing so because we use well water, and if the refrigerant lines broke they could contaminate the water (something to consider in the future when we are talking about alternative refrigerants, I suppose). My dad has the same thought process you do though- if he were to ever build a house again it would be designed with a ground source heat pump from the get go.

I live in Brooklyn NY, and my landlord got a government rebate to switch the whole house over to New split units system. So we got 5 big outside units, 28,000btu each. and I got in my room a 9,000btu indoor until. I'm kinda excited to see in action, it's almost completely installed already, should be working in a couple of days already. My landlord got The Comfort-Aire brand. My next door neighbor also used this gov program to convert his house like a month ago. He also got the same 5 outdoor units, but he got a different brand, Westinghouse. His has been working for like 2 my weeks now, they're loving it. I can't wait to have mine working. Btw I watched your other video on how these heat pumps work, I loved it. It explained a lot to me. And I also loved seeing my neighbors new system have ice building up on it, and I remembered it explanation on how it deals with it, so I actually stood there waiting to see it defrost. And after a couple of minutes, I could hear it shut down then restart, defrosting it in second, then reversing the flow again. I loved seeing it. I even explained it to the new owner. He was amazed by it too. So thanks for enlightening us all

“Management was just really bad about marking it when they built the place” Don’t blame Slartibartfast. He was just responsible for the fjords.

My grandparents home had a water loop heat pump installed in the early 1980s. It pulled heat from the water that came from the well and presumedly returned heat to the water stream when it was in cooling mode. The only part I thought was odd (and these days would be considered really wasteful) was that if water wasn't being used somewhere else in the home, the heat pump overflowed it outside and into a creek... All that being said, it did work fairly well, and they had wood heating for backup, which was rarely used since we live in western Oregon.

Here in Sundsvall Sweden we have a whole suburban area that is heated up with water pipes underneath the ground from excess heat from a powerplant nearby. That's about 3000 homes heated up or something like that with almost no extra fee. In fact the powerplant nearby was so eagerly telling us neighbors about this at an open house event that it was all their own idea to help the neighborhood being more environmentally friendly. The powerplant nearby is producing something from salt for usage in chemical processes, the powerplant is so hot that the doors are open up all year around to help the workers cope with workspace environment.

Dude, your channel just gets better and better! A balanced, informative and sensible info package...way to go!

As a European (Swede to be precise) the facts that surprise me the most are not the "cool ways we can heat our homes", because most of those were ways we're using on a regular basis. But stuff like using propane (or other gases) to heat clothes dryers is weird and shocking to me.

I intern for an HVAC company doing engineering. These videos are amazing. I watched before I started the more heavy stuff because I love this channel, and it helped me in my job. Thank you Alex for amazing content

I'm buying a home that is all electric and has a heat pump. I was initially concerned about how well they work since I'm in central Ohio. After watching this video and you last one, I'm very confident that my home will stay very warm. You have been a trusted source of information for years and I value everything you say more than any other source

This is just one of the best shows out there. I love your calm midwestern man voice. Actually you remind me of RBCP off the phone prank shows. And then the end credit music just makes me feel all warm and cozy. Thanks, man. Keep it up.

In Norway household thrash that can't be recycled is incinerated as efficiently as possible (landfills are banned, they're horrible for a ton of reasons), and the heat is sent to apartment complexes and other buildings. Should be standard everywhere. Near total carbon capture from the incinerators is also possible (although not common yet), that way you'll get nearly totally clean energy from thrash.

Too deep alert should definitely be a recurring ting in future episodes. I love it!

Another great video! Lots of great information, in a easy to understand format! Changing the heat pump reversing valve with the compressor running (and making a lot noise each defrost) is typical on most home heat pumps, but when I installed my Goodman unit in 2014, I was surprised it does shut off the compressor each time it starts a defrost cycle. Before 2010, I think all of them would change to defrost without wanting to shut off the compressor. But times change. I have been called out to homeowners who just got a heat pump, and they said "It's not doing it right now, but it make a terrible racket about once every 90 minutes". I would describe the racket, they would say "Yes that's it!" I would charge them $125 for the service call and leave. . .. Well make sure it is running normally too, but still charge them for my hour to come out there. With a R-22 heat pump, the typical outdoor refrigerant pressure was only about 30 - 45 PSI when running on a 30 - 45F day, and they did not collect a lot of heat. While my R-410A system can collect a lot of heat and the outdoor refrigerant pressure is fairly high, around 100 PSI. This provides a lot more heat inside, because the compressor heats the R-410 to well over 130F - even on a cold day. So you might hate your heat pump because it is to old, they changed to only allow the installation of R-410 systems after about 2005. I had a temperature alarm on my heat pump to monitor it. Actually a meat temperature sensor, so at 165F the alarm would start beeping, and that only happens when it is around 55F outside, (or warmer) and the heat pump runs more than about 30 minutes in a row, the heat keeps building as it runs longer each cycle, a good thing. Your talking about getting 50F water out of the ground loop heat pump system, 50F is being very optimistic, and if you measure a system in the Chicago area, you might see 40F but likely if you are cooling the loop, by heating your home, the water will come out around 20F temperature range in the winter. Usually after a couple of years, the ground loop will keep getting colder, and the savings will drop every year. The Bore Hole might be providing the warmer output water, by reaching very deep, and collecting heat from a volcano or something well below your home, or from a lot of water to heat exchanger below your home. Typical cold water from the faucet in Chicago is 41F, and that would be the very highest water that you could get from a water loop, when the heating system is not running in the heat mode. In Florida, it is possible to get 65F water from your faucet and water loop too. But after heating a home in Florida for a hour or so, the water loop will be in the 35F to 40F range. I have a Airtemp brand heat pump water heater. It is about the size of a upright window air conditioner, and has a 12,000 Btu compressor in it, just like a portable Air Conditioner would have. It has a 15,000 Btu heat output, so much faster than the typical electric water heater, while using about 1/4 of the electricity, they plug into a 20 amp 120 volt outlet. Airtemp was sold by Chrysler Corporation, and they stopped making Airtemp products in 1979, due to Chrysler almost going bankrupt. So heat pump water heaters have been around a LONG time. It also air conditioned the garage it was mounted in. It supplied about 20F cooler air to the space it is mounted in. Modern heat pump water heaters use way to small of a compressor for my liking. It is something like a 2,200 Btu compressor, about double the size of a refrigerator compressor. So TINY! A 4,500 watt electric heating element is 3.4 Btu's per watt, or about 19,000 Btu;s per hour. Also if mounted in a attic, they will switch to only electric heat if the temperature exceeds the limit, I think it is max compressor run temperature is 125F inlet air temp. They did use carbon dioxide to cool movie theaters back in the 30's but a small leak could cause everyone to fall asleep forever. They also used ammonia to cool the air in theaters too, but that could cause everyone to faint if there was a leak, or trample each other looking for the door. Imagine a gallon of windex sprayed into the air! And the ammonia they used was not diluted by 99% like Windex. So they started to cool the water loop, then use the chilled water loop to cool the theater, thus it became a non-toxic way to cool the air, without danger to anyone. Water chillers are still used today in larger buildings, even though most use refrigerants to cool the water loop, not CO2 or ammonia. There was a company that used a unit that looks like your heat pump, they used CO2 (as a refrigerant) to heat water in a water heater connected to the unit. They produced about 20,000 Btu's per hour, and worked great, but the company went out of business. You can also buy a new refrigerator with CO2 refrigerant in a reach in commercial refrigerator. There is also a company that is making refrigerators using propane as the refrigerant. If you ever see R-290, it is propane, in a very pure type, with no moisture in the propane. The propane boils just like the refrigerant in a normal refrigerator. Another air source heat pump water heater is a Mitsubishi City unit. They typically have a outdoor unit connected to several indoor coils, up to 30 of the indoor units. One indoor unit can be a 13,000 Btu or 30,000 Btu water heater / cooler. I worked on a City Unit that used cold water or hot water to precool or preheat the air in the make up air unit that supplied air to the building, and the heat pumps inside. So with a normal building heating or cooling system, they typically have 10% to 20% make up fresh air, to keep the oxygen levels normal all day long. But with a ductless heat pump like you have in your garage, there is no "Make up air". Fine for your garage, but not for the retirement center where our system was located. We needed to supply about 3,000 CFM of make up air to the 75 rooms in the building, thus the make up air unit with the cold water in the summer, and warmed water in the winter. I think that the Mitsubishi City units will become more popular, especially to heat hot water. They already work great to cool and heat spaces. Restaurants can use a lot of hot water, especially for dish washing.

If I can ever afford to build a house, it'll totally have geothermal heating. It'll also have this fireplace called Leivinuuni, which can be used for cooking stews, Christmas ham, maybe even baking bread or pizza? Just for some extra heat, just in case something goes wrong during wintertime. Oh and ofc as a Finnish person I need to have a Sauna in the house. That'll help with heating too.

yet again you've done an amazing job of making me incredibly angry at my household appliances. my wife is becoming concerned about my mood swings.

lol the subtitles at the end: "Geothermally Smooth Jazz"

Preaching to the choir here, brother! When our fuel tank came to its "expiry date" (as far as the insurance company was concerned) we took the plunge and scrapped our oil-fired furnace for a ground-sourced heat pump system. The installers drilled a single 100 meter vertical hole in our back yard for it, and adapted our forced-air ducting. There were government programs that gave us a couple thousand dollars in rebates as an incentive. Much cheaper to run now, and - Yay! - cheap air conditioning in the summer. It's much quieter than our old system and the furnace footprint is about half that of the old system. One difficulty facing suburban home owners is getting the drilling rig into place, but I gather that they (who? I dunno) are working on designing more compact rigs that can fit between houses and into back yards. I asked my wife if our home insurance went down any, since there's no more fuel tank in the basement, but she said it actually went up a little bit because now the market value of the house is higher. I can live with that.

Wow! You crushed it. This half hour video covered so many topics I've been thinking a lot about, and you confirmed many thoughts, filled in gaps, etc. I still can't believe I learned more about CO2 as a refrigerant and more about heat pump dryers in the same video. You confirmed medium-confidence ideas of mine while teaching me plenty more and you bring the polish of confidence and pertinent detail.

"We should only consider solutions that cover every possible situation" seems to get brought up a lot with expanding bicycles and transit. It's so tiring.

"only solutions which cover every single possible contingency are feasible!" That pretty much sums up every argument against electric vehicles I've heard.

We live in Pittsburgh and have a heatpump. After moving to a different home for a short time without one, I will personally always prefer a heatpump system. Ours is particularly nice in that the thermostat while not quite as intelligent as dreamed of here, does allow you to step in and say "alright... the pump isn't enough anymore" by turning on Emergency heat mode. We have only ever done this 1 time.

Another excellent series! Your comprehensive and well thought out videos are (as I see below) making their mark on future homes - just as they have with me! THANK YOU for your GREAT work!

I love how there was a card flashing on my feed when you said "But sometimes." I know EXACTLY which video it was suggesting.

I know this video is old in cyber years. I would just add that my parents bought a house partly because it has an alpha type version of a heat pump from the mid 80's that includes solar, geothermal and what is called and ice stick/ispind (a metal tower much like the radiator on the heat pump you have shown) It heats up both their house and their water for showering ect.. It actually works really well. Its only two draw backs is: you have to be careful while taking a shower during the summer as you might burn your self, and if it breaks down you need an engineer with a back ground in plumbing to fix it, that was also actively working during the 80's- since its quite niche. They live in a part of the world where cooling is hardly ever needed, so I haven't seen how well it works with that.

8:09 Our boi just casually dropping TMBG references. I see you, and I respect you.

This whole heat pump series has been an excuse to make that "I'm pumped for it" joke, wasn't it? WASN'T IT?!? CHOKE ON YOUR CANDOR! Oh, you did. Good. Balance to the universe restored.

I'm glad to see Alec doesn't need to nearly blow out his colon to summon a card anymore Edit with reference: ukposts.info/have/v-deo/r5hllY2RiaqF2Ik.htmlm15s

When our merely five-year-old A/C compressor bit the dust last summer, we replaced it with a reversible model. Our house also has oil heat for those really cold days. You are spot on - there is nothing wrong with a hybrid solution that use heat pump technology when efficient and fossil-fuel technology when necessary. I wish the powers that be would recognize this.

Well you usually combine the heating and hot water here in Germany on new systems. You get a 1000 liter tank which has a heat exchanger at the top to do "tank less" hot water. Hot water is then looped to each bathroom with a pump which runs like 2-3 times a day for some minutes. The natural gas, wood, heat pump etc boiler has a dedicated loop which just runs to an heat exchanger in the tank. Usually you add a resistive heater as a backup heat source if the main unit needs a repair or a service. Vaccum solar collectors do most of the year the base charge, usually you don't need to run the main heater at all, since the solar collectors are enough.

4:57 You're assuming the makers of those heat pumps actually care about not going too rough on the compressor, so it doesn't die an early death. I'm not sure I share that belief.

Dude you're the hero we don't deserve. Thank you for teaching me SO much stuff.

We have a water furnace. It draws the heat from ground water and reverses in the summer for AC. All we needed was our basic well pump, a lot of plumbing, and a return to the aquifer. A bonus is that the furnace also circulates water through our hot water heater so we have a constant reservoir of hot-ish water that is topped off by the electric resistive elements. I love it.

Ground source heat pumps are the way to go but installation costs are the main inhibiting factor. In Toronto Canada I buried temperature sensors at different depths. Even at 14 inches it only got down to 4.5C in the middle of February. Apparently the frost line is not very far down. But how important is ambient soil temperature? To extract heat you need a certain length of buried pipe and a low fluid temperature. I made a water to water heat pump out of 2 window ACs, 2 vats of water (antifreeze), pumps and a Raspbery Pi controller. Buried about 100 ft of pipe in 1 ft deep trench and a couple of 5-9 ft holes. i have radiant floor heating, an efficient gas boiler, an Air Source Heat Pump and now, with the GSHP I have not had to run the boiler yet despite temps down to -6C. i've spent about $3K. Affordable DIY ground source heating seems possible.

I always get excited for and think about changing everything in my house to heat pump technology before remembering that I'll likely never be able to afford to buy a house.

My Fancy Pants Carrier Infinity system has a thermostat/controller that does exactly what you say! It monitors coefficient and will supplement with "Emergency Heat" when needed, you don't even notice what's going on. It can also take in energy cost data as part of its decision. It's a fantastic system that is so efficient it will even run when my home backup generator is powering the house.

I was already researching heat pumpy things without having watched either video, knowing full well that I would need to watch this two-parter. Now, one, I’m glad I did, and two, I want heat pump everything now.

In 2006 I installed a ground-source heat pump on my property near Denver, and it is (mostly) powered by the solar PV array on my roof. I pay only the service charge for electricity 10 months of the year. Plus I got Cooling as well. My roof space wasn't quite large enough. Everything works great, and I use a modern fireplace as my backup. One thing to note is that my heating is slower than a natural gas forced air furnace system so you need to design the ducting accordingly to eliminate "drafty" feeling air movement; or install in-floor radiant heat loops hooked up to the heat pump

I love how Alec calls vertical drilling "new" when I've been hearing about it for two decades in Sweden. 💙

Mechanical engineer here. I absolutely love when you cover topics like this

Investigating self-building a house right now. Did not know heat pump dryers were a thing. Will be looking at adding that to the plan. Thanks for all the informative videos!

Having had a geothermal heath pump for 20 years, with a 200 yards vertical hole I can only attest to strength of this solution , and I can easily recommend it to others. This costed me around $12000 when installed. Added on to this I use the brine as free cooling in the summer.

Talking about trying to heat cities reminds me of Toronto's way of cooling skyscrapers. A company called Enwave pumps water from deep in lake Ontario up and through buildings in the downtown waterfront then back out into the lake.

TC: "Management was *really* bad about marking the location of the frost line!" Management: "We apologize for the inconvenience."

One interesting article which I red recently was about one local parking hall for about 800 cars what they are building currently. In summer it collects heats and pump it to ground in about 50 meters depth. They say that the ground can store over 11GWh of energy during summer which they can use in winter to heat it without using any external energy for about 6MW heating power from the ground.

This is one of many of your videos that is directly applicable to my situation and has been both enlightening and helpful. Keep up the great work.

"engineers are smart" me an engineer: "eeehhhh I wouldn't bet on it."

Oooh, that heat pump dryer looks amazing! My schedule usually results in my clothes going in the dryer for way too long anyway, so if it takes longer I'm not actually losing anything.

This is video made me buy a heat pump dryer and i love the thing. I now have two extra 15a circuits in my laundry room thanks to the shim it came with and that's neat

Chicago - digs (or drills) underground to get heat. Coober Pedy - builds underground to avoid the heat. Life is complex. Another brilliant video, informative but with the right amount of humour.

I know people leave lame comments like this all the time, but dear god, I LOVEE this video. I had to pause every five minutes to let my brain settle after you've been clarifying solutions to questions that have been in the back of my mind for years, while re-affirming my beliefs that green energy isn't a myth. A few years ago, I was toying with the idea of using the waste heat from room-sized freezers in commercial kitchens to help heat their ovens / deep fryers. Thank you Mr. Connections.

In Israel, where I live, the boilers are connected to sun batteries on house roofs to heat water in the summer, which is most of the time. The water is circulated over black pipes encased in thin glass front, black rear boxes. It is a great solution for us. edit: You obviously addressed this, but it was my first thought. The bane of commenting before watching the whole video...

I don't have the time to read through all the comments to see if anyone else has brought this to your attention yet (I would hope so, but just in case) many if not most water source heat pumps have hookups where they can also heat your homes hot water (I would assume mostly in the summer when the system is in AC mode). This saves even more energy costs as the hot water heater doesn't have to run as much if the water going into is already warm/hot from the heat pump. Great job on the video's I've been enjoying them.

Some companies are using directional drilling (same equipment used to bury fiber, gas, electric, etc) for geothermal ground loops. This works on relatively small lots because they can drill from front to back right under the house or anything else in the way. Little land disturbed like with the vertical option but generally cheaper.