Technology Connections
17 HN recommenders · recommended in 18 months, 2021–2026
35:15 · 4.9M views · Feb 28, 2021
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.
HN's default recommendation for a friendly, thorough introduction to heat pumps and why they are so efficient.
20 comments from Hacker News
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!
Highly recommend the YouTube channel 'Technology Connections' videos on heat pumps: this video [LINK] [LINK] [LINK]
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]
> 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
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]