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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

#91

Post by seiferteric »

amazingman wrote: post #19
hnburnsy wrote: post #12

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.

This is exactly the kind of thing government is for, even though it's missing the other half: subsidies. At the very least buying heat pumps for the next 5 years should be tax deductible. Even better: a $2000 or similar rebate.

The problem is, energy use is only one part of the equation. Often times new appliances that are more efficient end up being more prone to breaking due to more complexity and companies trying to cut costs to meet a price point. This leads to people needing to replace there appliances much more often which really makes me question how much energy is actually saved if you include the energy used to produce them...

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

#92

Post by lizknope »

jandrese wrote: post #62

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…

Ask This Old House had an episode literally yesterday where they installed a \ solar-assisted split heat pump water heater. There is a component that goes on the outside of the house but not on the roof which simplifies installation.

https://www.youtube.com/watch?v=uqyAWkXXt3A

https://www.neshw.com/residential/solar-heat-pump-water-heat...

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

#95

Post by Youden »

baggachipz wrote: post #86
gwbas1c wrote: post #84

Earlier quoted context omitted.

You're about 20 years behind. My heat pump is working great at 0F. It's 7 years old.

heat pump for house !== heat pump for hot water

I don't know what it's like where you're living but here in Switzerland it's completely normal to have one heat pump that does both. Here there's a lot of floor heating, which also uses water, so you usually just run one loop to the "boiler" (a water tank with a copper loop for the water from the heat pump to circulate through) and one through the floor and have a valve to switch which is running through the heat pump.

I have one of these: https://cta.ch/en/private/products/ah-i-eco-innen

I got it in October so most of the time I've had it has been <10C. It's produced 806.3 kWh of heating for hot water and 6587.2 kWh for the floor heating. It consumed 302.7 kWh and 1801.4 kWh respectively, for a COP of 2.66 and 3.66.

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

#96

Post by karussell »

hedora wrote: post #10

I wonder if this can store any heat or just heat pump heat. If it can store any heat, it would help a lot to further reduce heating costs in our modern energy efficient house. Sometimes, in the winter, we get too much solar forcing, so if we don’t heat all, it can be 85F in the day in the house, but 60-65 at night. (We open the windows during the day, and don’t always close them at exactly the right time at night.)

I think this can work and instead of that the heatpump pumps the heat into your house (when "solar is plenty") it would pump it into the storage. (I have a similar setup, but heat the water but of course this is rather limited)

unrelated: a simple technical solution to your window problem would be home assistant and a few sensors to notify you when the windows are open too long or open when too cold inside.

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

#97

Post by Loughla »

chankstein38 wrote: post #57

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.

And yet, if you make it like I do, there always manages to be one piece that is ice cold while the rest is shockingly hot. Even if you're start with warm ingredients.

Physics does not apply to lasagna.

Also I suck at making lasagna.

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

#98

Post by mike-the-mikado »

gwbas1c wrote: post #90

The article omits some critical details: It says this is both a "heat pump" and also "storage" AND says that it will run when electricity is cheap or plentiful. Thus: 1: Where does it pump the heat from? (Or is this not really a "heat pump" and instead is using resistive heating?) 2: How long does it store heat? Is this something that will store heat on a 24-48 hour basis, or will this store heat during the spring /…

I would guess that is intended for a daily cycle, perhaps using air source heat pumps at times of day when the air temperatures are higher and electricity prices are lower, then using it as required.

As it works on phase change (e.g. think of melting ice) heat is added (or removed) without changing the temperature of the store (which, I guess, might be hotter or colder than where the heat is extracted or used).

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

#99

Post by IshKebab »

gwbas1c wrote: post #90

The article omits some critical details: It says this is both a "heat pump" and also "storage" AND says that it will run when electricity is cheap or plentiful. Thus: 1: Where does it pump the heat from? (Or is this not really a "heat pump" and instead is using resistive heating?) 2: How long does it store heat? Is this something that will store heat on a 24-48 hour basis, or will this store heat during the spring /…

1. The device is just storage. It would be paired with an air or ground source heat pump.

2. With good insulation you can easily store heat for a day which is all you need. You're never going to get close to storing summer heat for the winter. That's not impossible but not feasible for something this scale (and not cost effective at any scale).

3. You just heat it up and cool it down. There are no fancy chemical processes happening other than the phase change. It's exactly like a phase change hot/cold pack you can buy on Amazon.

4. I'm pretty sure this is designed for domestic heating...

It's kind of an obvious idea tbh. I don't think they've done anything super innovative... They made an aluminium heat sink..

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

#100

Post by karussell »

Xylakant wrote: post #65
mrguyorama wrote: post #60

Earlier quoted context omitted.

Efficiencies and effects are at the point where taking a photon, converting it into an electron, and using that electron to pump heat is more efficient than turning that photon perfectly into kinetic energy. Similarly, in mild weather, it is more efficient to burn hydrocarbons and turn it into electricity to run a heat pump than use that hydrocarbon for it's heat energy directly. Pumping heat is more efficient than m…

Thermal solar panels have the advantage of being very simple and surprisingly effective. But if you're lacking space to put up both solar cells and thermal, you can use combined panels which have a solar cell with a backing thermal system. The interesting thing is that these combined panels outperform solar cells even when it comes to electricity generated because solar panels loose efficiency as they heat up, so coo…

The problem with thermal solar panels is that you can use its heated water only if it gets warmer than the water in your system, which is not always the case, especially in winter.

Compared to nearly 100% usable energy from normal solar panels.

Furthermore if you have a heatpump you can convert this electric energy into heat energy with a factor of >3 (COP).

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