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

sintef.no

71–80 of 243 posts

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

#71

They should've used lasagna. You could be in a tundra heating it over a fire and, as long as you get it sufficiently and consistently hot, it'll still burn your mouth 20minutes later.

I was recently wondering if any particular type of food contributes to mouth cancer prevalence and I concluded that at the top of that list would be be lasagna and cherry tomato on a pizza/in a soup.

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

#72

I've been keeping an eye on heat pump water heaters for awhile, but right now they mostly make sense in warm climates. The big problem is they're still specialty products and marked up like crazy, but also they tend to use cheap components which makes them loud and prone to failure. If you run A/C for the majority of the year then they pay themselves back reasonably quick, barring early failure, but in colder climate…

They use them a lot in Norway, it's hardly warm there.

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

#73
post #66

I've been keeping an eye on heat pump water heaters for awhile, but right now they mostly make sense in warm climates. The big problem is they're still specialty products and marked up like crazy, but also they tend to use cheap components which makes them loud and prone to failure. If you run A/C for the majority of the year then they pay themselves back reasonably quick, barring early failure, but in colder climate…

I had a heat pump installed in 2010. In a cold climate. Only used for heating. It paid for itself extremely quickly - less than three years. It's still going strong, in 2026. It's important to maintain it regularly, i.e. deep cleaning every two years or so. The first time I got a company to do it for me, and the technician taught me how to do it all by myself, so that's what I do. In any case having a professional do…

What did you heat with before?

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

#75
post #69
post #67

Earlier quoted context omitted.

I think a heat pump only for water isn't the right way to go. In the EU, new systems I see use a single heat pump for all heating and cooling in the house including heating water. I do miss my natural gas on-demand water heater from when I lived in the states though. Unlimited hot water was nice, and it took up almost zero space.

Which models are you looking at? I was still quoted separate pumps for floor heating and a boiler with the pump built in taking the energy from the air two years ago. Is it something from nefit by any chance?

This is promising.

https://www.pv-magazine.com/2026/01/29/samsung-releases-new-...

> The South Korean giant [Samsung] said its new EHS All-in-One provides air heating and cooling, floor heating, and hot water from a single outdoor unit. It can supply hot water up to 65 C in below-zero weather.

> Dubbed EHS All-in-One, the system provides air heating and cooling, floor heating, and hot water from a single outdoor unit. It is initially released for the European market, with a Korean rollout expected within a year. “It delivers stable performance across diverse weather conditions. It can supply hot water up to 65 C even in below-zero weather and is designed to operate heating even in severe cold down to -25 C,” the company said in a statement. “The system also uses the R32 refrigerant, which has a substantially lower impact on global warming compared with the older R410A refrigerant.”

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

#76
post #67

Earlier quoted context omitted.

I think a heat pump only for water isn't the right way to go. In the EU, new systems I see use a single heat pump for all heating and cooling in the house including heating water. I do miss my natural gas on-demand water heater from when I lived in the states though. Unlimited hot water was nice, and it took up almost zero space.

Afaik heat-pumps in the EU can provide unlimited hot water–what am I missing?

Geothermal (and airbased) pumps theoretically do not have unlimited heating capacity. For example my pump (Daikin Altherma Geo 3) has a 180 litre water tank so it can ”only” supply 180 litres hot water at 65 degrees Celsius and takes about a minute to heat two additional lites.

So if I want to quickly scald myself in a 400 litre pool at fifty degrees I can’t. But if I had a gas heater that would be possible!

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

#77

Stones has the ability to store heat and keep cool. What's all this fuzz about ?

It's all about efficiency. You can store heat in anything, but the question is for how long and how much energy can you get back out later. The first part is easy and how we got ovens and stoves, the second part can be pretty tricky depending on your requirements. Large scale energy storage sometimes uses massive amounts of sand for example, but they heat it to hundreds of degrees which is not really feasible in most settings.

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

#78
post #67

I've been keeping an eye on heat pump water heaters for awhile, but right now they mostly make sense in warm climates. The big problem is they're still specialty products and marked up like crazy, but also they tend to use cheap components which makes them loud and prone to failure. If you run A/C for the majority of the year then they pay themselves back reasonably quick, barring early failure, but in colder climate…

I think a heat pump only for water isn't the right way to go. In the EU, new systems I see use a single heat pump for all heating and cooling in the house including heating water. I do miss my natural gas on-demand water heater from when I lived in the states though. Unlimited hot water was nice, and it took up almost zero space.

While they are not as efficient or flexible, they are many times more efficient than resistive electric water heaters. I've installed one with in house air intake (due to construction reasons) in my house and it cooled down the basement by a few degrees (and removed air moisture as an added bonus). In summer the thermal capacity of the ground heats up the basement again, in winter it's a bit cooler, but it still works efficiently.

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

#79
post #2

I would love to see a bus-sized version for year-long temperature moderation. Like, drop house heat into it during the summer so it can re-heat the house over the winter, and pull all the heat out of it by Spring so that it can cool the house over the summer. Bus sized because that amount of thermal mass is bound to take up a lot of space, but capable of being buried so that it doesn’t actually take up property space…

I live in a climate where, for most of the year, the daily high-low temperature range includes 20C, so I'd like a whatever sized one is needed to average that out, and run most of the year without any active heating or cooling.

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

#80

Related, TIL the US is effectively banning residential electric resistance water heaters in 2029, with heat pump water heaters being the only type that can meet the new standards. Users will see a 2-3x in cost difference and a 3 to 8 year payback on savings.

The problem with heat pumps replacing electric heaters (in cold climates) is that the waste cold air gets dumped into the house and needs to be heated again. Generally, electric water heaters are expensive to run compared to gas ones, so people use them in places a gas heater is not possible to install (e.g. no way to vent the exhaust). This also means that the heat pump would have nowhere to vent cold air.

This kind of thing is why I don't like bans like this. The specifics matter a lot.

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