17 HN users recommended this explainer15 months2021–2026score 16
Years with an HN recommendation, 2007–2026
HN's default recommendation for a friendly, thorough introduction to heat pumps and why they are so efficient.
Technology Connections explains how heat pumps work as reversed air conditioners and why they can deliver several times the heat of resistive heating per unit of energy. It also tackles common myths such as poor cold-weather performance.
“Start here for a good introduction to heat pumps and how they are so efficient” (HN, 2021)
His whole channel (called Technology Connections) is probably my favorite one on YouTube, can’t recommend it enough! My favorites are his series on refrigeration and heat pumps, for example this one: [this video] Edit: to clarify, this article is based on an old Technology Connections video, and the creator of that video has lots more!
Favorite channel with series on refrigeration and heat pumps
> no wasted power Electric heating can be much more efficient than what's effectively resistive heating with 500%+ efficiencies being possible. Search for "heat pumps" or watch: [this video]
> So the heat pumps can also do cooling during the summer? Here's a pair of really great videos about heat pumps and what they can (and could, in the future) do: [this video] [link]
This video is a great explainer on heat pumps [1]. The TL;DR is that they are essentially nothing more than air conditioners that run in the opposite direction. Plus, a heat pump and an air conditioner can be combined into a single system. 1: [this video]
Great explainer: heat pumps are reversed air conditioners
> I'm wondering if there's any low-energy or green solutions to this. The answer is "it depends". How your flat is designed will have an impact on what you can do. But if you are able and willing to do some house work, there is a lot you can have control over. At the end of the day, it's all about how you can control humidity, the flow of hot and cold air and humidity. At your disposal, tools such as conductive materials, insulating materials, etc. Google "passive house" to see the concept and what these things use. With that said. Heat pumps are incredibly efficient, and replacing your heater with a reversible air conditioner which you can then run in both summer and winter will do far more for your overall energy efficiency than anything else you can do. Most of your energy consumption comes from winter-time heating. Start here for a good introduction to heat pumps and how they are so efficient: [this video]
Good introduction to why heat pumps are so efficient
Our house is electrically heated via a heat pump, which has appreciably more efficiency than a resistance heater (or computer). Here's a neat video about them: [this video]
Neat video on heat pump efficiency over resistance heating
There are highly efficient heat pump powered water heaters, going out anywhere remote, these and other heat pump systems should really be used. This is a really great overview [this video]
Thankfully, you are wrong about that! Just like you don't need a cooler source _from which to source cold_ in the summer with AC. Technology Connections has a fun (well, to me) video on how heat pumps work and are great. Literally just AC units running in reverse, thanks to having a valve. [this video]
Technology connections did a great video on heat pumps. [this video] One of the best things is that is an air conditioner you run in reverse to get some heating.
Great video explaining heat pumps as reversed air conditioners
I feel like it's almost a requirement to take this opportunity to share Technology Connections great video [1] on the topic. Personally, I've used a heat pump as the sole heating unit for my house for the past 6 years or so. There have been a few cases where I've opted to use an extra blanket, but overall the results have been pretty impressive, and the cost savings are pretty huge. (Apartment, so no fuel heat, it's electric or nothing) [1] [this video]
Great video on heat pumps, backed by personal experience
It feels obligatory to reference Technology Connection in a thread about heat pumps. TC is a super fun YouTube channel that digs j to everyday technology and has had a number of episodes on heat pumps and modern thermodynamic management challenges and technologies. [this video]
Fun channel digging into everyday technology and heat pumps
They are great if you are looking to use electricity to heat because they are 3 to 4 times more efficient than resistive heaters. It depends on the price of electricity and other heat sources in your area. If you live in the north where temperatures go below -15 Celsius, air-to-air units aren't as great because they lose efficiency as it gets colder outside. My heat pump has a COP of 3, meaning it can generate as much heat as a resistive heater using 1/3 the electricity, but it shuts off at -15 Celsius because below that point it is less efficient than resistive heat. If your heat pump has a COP of 4, you might get to -25 Celsius before it is less efficient than a resistive heater. Better, but more costly, heat pumps use in-ground water, either from a pair of wells, or from a deep pond that won't freeze to the bottom, or from many meters of water pipe buried deep enough beneath your lawn to not freeze in the winter. Because of the depth, they always have access to the earth's heat so they don't lose efficiency in the winter. The Technology Connections YT channel has a couple of good videos about how them: 1. [this video] 2. [link]
He made several excellent videos explaining residential heat pumps: [2021-02-28] [this video] "Heat Pumps: the Future of Home Heating" (35m14s) [2021-04-01] [link] "Ground Source / Geothermal Heat Pumps and Other Info" (28m03s) [2022-03-26] [link] "Why Heat Pumps are Immensely Important Right Now" (21m02s) [2022-04-13] [link] "Heat Pumps are Not Hard: Here's what it will take to start pumping" (46m32s)
This guy[0] has done quite a few deep dives on heat pumps that cover a lot of the myths (eg they don't work in the cold). It's pretty interesting material if you're thinking about a heat pump. It has always seemed silly to me that we spend money to keep a box of cold (fridge) inside the houses we're spending money to heat in the winter and spend a lot of money to heat up dryers, stoves, etc in the houses we're spending money to cool in the summer. Watching these videos made me think there's a real possibility at some point to have something like a whole home heat pump that just moves heat from where it is to where you want it and in the process reduces the need for systems working against each other to heat/cool specific parts of the house. I understand there's something in commercial settings that has this capability but I'm blanking on the name. 0: [this video] 1: [link]
Deep dive debunking heat pump myths like poor cold performance.
They are a very efficient way to get both AC and Heating: [this video] [link] Unless you live in a cold climate, they are worth it for a discounted energy bill =3
The first answer tells you why you are wrong. Heat pump. It's a silly question trolling for the obvious first year engineering/high school answer, heat pump. In practice how heat pumps work in the artic circle might be interesting. But in practice light bulb in the article are probably working to government rules for the entire country. Or practical limitations like exposure to the cold or transport costs or what's getting mass produced in society. Post internet heat pumps have become quieter and far less in cost that's why they are popular now (and trolled for karma) Technology Connections talked about them in an ok vid - [this video]
> An A/C is a heat pump. Stop trying to change existing terminology I am not trying to change existing terminology, I am using existing terminology. Air conditioners (A/C) are devices sold to only cool a house: * [link] * [link] * [link] Heat pumps are devices sold to both cool and heat a house: * [link] * [link] * [link] See also US Department of Energy: * [link] And most definitively of all, Alec of Technology Connections : * [this video]
Authoritative source on heat pump versus air conditioner terminology
>heatpumps and other gimmicks Anecdotally, two of the smartest people I know love heat pumps—doesn’t Technology Connections too? Was probably this: Heat Pumps: the Future of Home Heating [this video]
Technology Connections video on heat pumps cited as likely source.
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