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Joined 11 months ago
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Cake day: August 2nd, 2023

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  • Damn. The other day I received a notification from my local post app about something very important that has landed in my PO box when I had just arrived at home from work. I was curious and checked my emails for the exact time stamp of the delivery, turns out it was not “just now” like my Android notification implied but 12 minutes ago. Incidentally, 12 minutes ago was pretty much exactly when I cycled past my PO box being really disappointed that my package hasn’t been delivered yet, or so I thought at the time. Had to go back when I could’ve just picked it up on the original trip.

    Stupid me thought it was the “optimised” per-app battery setting vs “unrestricted” that would control this.

    Thanks for pointing this out OP!










  • schnokobaer@feddit.detoMemes@sopuli.xyzCan we please just have both?
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    8 months ago

    Loads of people love to pretend an NPP is just a hut with a magic gem inside delivering an endless amount of power for free. In reality they are huge, highly complex, high-security facilities that take decades and billions to build and need to be operated and maintained by loads of highly trained staff in 24/7 shift operations. This isn’t to downplay their merit of providing CO2 emission free power, but for the love of god please appreciate the enormous effort and expense this is achieved with, especially when comparing it to renewables.




  • And what is the problem with a gas hybrid heat pump? It’s an ideal solution for places that get very cold, use the gas furnace for the weeks when it’s below -5 and use the heat pump for many months around that. It’s one of the most efficient ways to use a heat pump as you don’t have to bully it through the coldest part of winter with very bad COPs, you’re only using it when it’s most efficient. And when your heating period is very long, that will only benefit your seasonal COP. So of course it’s more expensive than a simple furnace, but it will also save loads of energy and redeem itself after 5-10 years.

    The best part about this is you already have an AC, aka a heat pump, but you don’t use it for heating?



  • gas furnance that was somehow under-dimensioned – the idea is that in the real cold days you’d still have the good ole fireplace

    Oddly enough I’ve never encountered that in Germany, I only ever see catastrophically oversized furnaces that start cycling in March… Seems to me plumbers never really worry too much about correct dimensioning, they just put the same 20 kW furnace that they know and love to install in every apartment and single family home. For some it will be somewhat adequate, for some it’ll be oversized, who cares, customers never complain when the furnace cycles, but when it’s too cold, you’ve got a problem. Same as they’re never too worried about finding suitable supply water temps. Just set it to 80 and you’re good, it’s the customer who pays horrendous gas bills, not you lmao. That’s also why everyone thinks their Altbau has to have 80°+ supply water when they have never really tried anything lower to see if it maybe suffices. My parents had their oil-furnace on 80C supply for the past 40 years and last winter when everybody was trying to save as much energy as possible they figured out you can set it to 55 as well.



  • but assuming they’re saying that it’s saying that $0.63 worth of natural gas gives you the equivalent thermal output of 1kWh

    Correct (although $0.063), and interesting to see you seem unfamiliar with this, this is the standard way of listing energy prices in Europe, it’s not just that site. That site was just my first hit when I looked up Canadian energy prices. It’s the low heat value and it’s determined by the energy in a fuel if not allowed to condense (which is the relevant value for a traditional furnace, if you have a more modern condensing furnace you take the high heat value) and it makes it relatively easy to compare different sources of energy.

    Canada is huge, and some of that landmass is in the Arctic circle.

    What people never realise is that being far up in arctic climates doesn’t only impair an SCOP. Yeah the lowest temps are very cold, but that means temporarily bad COPs. An SCOP is made up of the whole heating period though, which in colder climates is longer, so in turn you have several months more of the time where heat pumps are extremely viable with temporary COPs above 5 or 6 saving loads of energy. The real problem is if your lowest temps are so low that a heat pump will stop working entirely, in which case you get a hybrid system or just leave your old furnace in as backup, which is even better for your SCOP because you omit the month(s) with the worst COP and only use the heat pump when it’s most viable. Let’s say you live in Tuktoyaktuk and heating period is basically all year, then you have your furnace on for 3-4 months but you’re saving massive amounts of energy with your heat pump in the other 8-9 months of the year.

    touching on the nuances of the word “efficiency”

    I actually tend to avoid using that term for heat pumps anyway, as it’s not really correct in terms of physics. What makes heat pumps so viable is a coefficient of performance, their actual electrical efficiency isn’t all that good at 50-60%, but it’s also kinda irrelevant. It’s sometimes easier to just call it efficiency, but like you say, once you go into the nitty gritty it falls apart.


  • People think that’s a killer argument against heat pumps when it absolutely isn’t.

    In that sort of climate you get a hybrid system or just leave your old furnace in as backup. You’ll use the furnace for the couple of days/weeks when it is below -25c/-13f and use the heat pump for the 6 months around that time window and save huge amounts of energy because you only use the heat pump when it’s most efficient. A hybrid system will improve efficiency because it combines the technologies at transition temps while just keeping the old furnace as backup is obviously much cheaper, since you can also get a smaller unit than you normally would because you don’t have to worry about the coldest period.