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Pretty soon, heat pumps will be able to store and distribute heat as needed

sintef.no

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Re: Pretty soon, heat pumps will be able to store and distribute heat as needed

#241

Post by moooo99 »

IneffablePigeon wrote: post #209
moooo99 wrote: post #169

Earlier quoted context omitted.

It does. However, the hotter the water becomes, the less effective the heatpump becomes. With anything beyond 60C becoming very inefficient. With hot water tanks, they are unfortunately pretty badly insulated as well, with some of them loosing heat very quickly. Depending on how you plan on using that water, you also have to make sure the temperature never dips below ~60C to avoid legionella from spreading. I actuall…

The legionella thing is a little overblown fwiw. 50 degrees is perfectly adequate, and you can go lower with very little risk if you set it to briefly bump up to 60 every week or two. Even that is not hugely necessary in a domestic setting. https://www.heatgeek.com/articles/legionella-and-water-tempe...

This is a heavy depends. Primarily on how well insulated throughout your home your waterlines are and how frequently they are used.

If you only have 50C in your tank and badly insulated lines, your temperature can dip below 50V very easily where legionella feel really comfortable.

Re: Pretty soon, heat pumps will be able to store and distribute heat as needed

#242

Post by coryrc »

modo_mario wrote: post #240
coryrc wrote: post #228

Earlier quoted context omitted.

1. No, absolutely not. Why would you settle for COP=1 when you can have COP>1? 2. The electrical to heat conversion efficiency is indeed 100% regardless of the temperature of the resistor. And if you're putting out 1000W, then all input losses are also identical. If you put a 1000W light bulb in the middle of your room, or 2 of them but run both at 500W, you'll get EXACTLY the same heat output in your room, but the s…

1. Are there not scenarios where it drops below 1? The stats for them always seem optimistic scenarios given what i hear from people during winter cold spell in houses that aren't absolutely perfectly insulated. If your water term needs to remain above 70C and it's starts freezing hard outside during winter when that COP starts to matter the most for example.

If there were, you installed the wrong equipment.

Re: Pretty soon, heat pumps will be able to store and distribute heat as needed

#243

Post by darkteflon »

Tor3 wrote: post #166
darkteflon wrote: post #163

Earlier quoted context omitted.

I’m in Japan too. Could you name the model you ended up going with? My heating bill in the winter is insane.

The model is not yet decided, we're in the finalizing stage with the building company. What we have been focusing on is a well insulated house, unlike the old one which has no insulation at all.. if we tried to heat that it would not only be extremely expensive, it's impossible to even heat the small bathroom with an electric heater. So instead you kind of get used to it. Took me a year to stop feeling like I was fre…

Thanks for your reply! We’re about to finally replace our windows with double-layer glass. Hoping this makes a big difference.
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