Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

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

sintef.no

Post reply on HN
Print view View original

81–90 of 243 posts

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

#81

Post by ortusdux »

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…

I'm in the northern US and am very happy with mine. I self-installed with a county rebate, so the total cost was a Saturday and $700. My old electric unit was EPA rated for $450/year, and the new one has averaged $170/year over 4 years, so I've already broken even.

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

#82

Post by AlexandrB »

lm28469 wrote: post #41
direwolf20 wrote: post #37

Earlier quoted context omitted.

Is the heat pump heater taking heat from inside or outside the house?

Depends on the model, but a lot use the air from their own room, that's why they can't be installed in small rooms. Models pulling the heat from outside are more expensive and require more labor obviously, and they don't make a lot of sense for places that are bellow 0c multiple month a year as the COP will drop to 1.x and you will most likely need extra electricity for the anti frost cycles

But dumping the waste cold air into the house when it's below 0C outside doesn't make much sense either.

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

#84

Post by gwbas1c »

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…

You're about 20 years behind.

My heat pump is working great at 0F. It's 7 years old.

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

#85

Post by snuxoll »

Tor3 wrote: post #66
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…

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…

Installed mini-splits to replace the propane stove that heated my house, DIY job, so all it cost was the units themselves and some materials.

Propane bill (no natural gas, town of 500) from Oct 24 to Feb 25 (installed the mini splits that month) was $1200, for just heating.

My mini-splits are on a dedicated sub panel with an Emporia Vue 3 energy monitor. $604 in electricity consumption, and that includes air conditioning over the summer months.

For what it’s worth, our winter weather averages 25-35F with the occasional few days dipping to tens, single digits, and the occasional -10 freak; but these units just BARELY have a HSPF4 rating to classify as “cold climate” models. Still going to pay for themselves in 6 years without any tax credits, and 4 or so since I still installed them when they were available.

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

#86

Post by baggachipz »

gwbas1c wrote: post #84
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…

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

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

#87

Post by drhike »

sgc wrote: post #26
hnburnsy wrote: post #22

Earlier quoted context omitted.

Heat pump water heater (hybrid/HPWH, e.g., 50–65 gallon equivalent): Unit prices range from ~$1,500–$3,000+ (most common models $2,000–$2,500), with total installed costs $2,500–$5,000 (higher if electrical upgrades or space mods needed). Average retrofit/install often lands around $3,000–$4,000.

Electrical upgrades are almost always required, and price is more like 7k-9k around here. It's going to be seriously painful for a lot of people.

Ehh 120v models exist. My 65 gal runs fine on a standard 20a breaker.

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

#88

Post by JoblessWonder »

mrd999 wrote: post #35
hnburnsy wrote: post #23

Earlier quoted context omitted.

These are credits that only work if you have owe federal taxes and they cannot be carried forward. I've seen estimates that 40-45% of taxpayers owe 0 or close to 0.

Eh? If you have income you owe taxes, Uncle Sam just takes it before you even see it

I think something like 25% of the population reports 0 household income.

(I don't understand the implications, it was just surprising when I heard that.)

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

#89

Post by themafia »

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…

> government mandate will force enough demand that manufacturers can enjoy some economies of scale

So you want the government to pick winners and you want to do business with a monopoly? This is the opposite of what you would want.

If the product saves me money, and it's _actually_ better, I will buy it in a heartbeat. If you're involving the government it's because one of those things isn't true.

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

#90

Post by gwbas1c »

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 / fall when longer days mean extra power from residential solar, and then use the heat in the winter?

3: Is the unit itself "warm" when storing heat? Or is the heat stored in a purely chemical way and needs to run through a catalyst or similar to get it back?

4: Can this be scaled up for general domestic heating?

---

Just an FYI: There are plenty of schemes with resistive electric water tanks to store heat when power is cheap.

Post reply on HN