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

Harnessing America's heat pump moment

heatpumped.org

Post reply on HN
Print view View original

301–310 of 571 posts

Re: Harnessing America's heat pump moment

#301

Post by ZeroGravitas »

neltnerb wrote: post #234

I've got to throw out an obvious explanation. A third of the country rents. Renters pay the utility bills. Landlords pay for appliance upgrades. Why would the landlord put any effort into upgrading appliances when the cost of not upgrading them is borne by the renters? I've never rented at a place where they didn't want to fix broken equipment with the cheapest possible replacement. And no renter would ever consider…

In some locations you can't rent out places without minimum energy efficiency ratings, which then leads to insulation and heat pumps getting installed.

Re: Harnessing America's heat pump moment

#302

Post by flakeoil »

edg5000 wrote: post #261
kortilla wrote: post #238

Earlier quoted context omitted.

Then why aren’t they in 2/3 of houses

They are efficient but do not have as high of an energy output as a smaller and cheaper gas furnaice. Apart from that, the water temperature is lower, so you need much larger radiators. Due to the lower energy output, you also need better insulation or a relatively massive heat pump. And the tech was not around 20 years ago (for reasons unknown to me).

The water temperature which you deliver to radiators are not defined by capacity of the heatpump, but how hot the radiators can be for safety/comfort reasons. If the radiators are too hot people could burn by touching them or stuff like platsic chairs would melt. Also the piping in the walls and floors cannot support too hot temperatures.

The temp for water used in radiators 60-70C is easily achievable by an air-top-water heat pump. It does not depend on the energy source, gas/oil/electricity.

Re: Harnessing America's heat pump moment

#303

Post by dzhiurgis »

chongli wrote: post #235
dzhiurgis wrote: post #226

Earlier quoted context omitted.

2k NZD to install minisplit vs 160KWh per winter month to heat my bedroom. Thats about $150 in power or 16 yrs to pay itself at COP 5. Or install 1 additional $130 solar panel to make about 650 KWh per year. Makes sense for living room tho.

Oh you live in New Zealand! Where I live (Canada) if you don’t heat the entire house then the pipes freeze and burst and then the whole house floods.

I do heat house main (using hp) just for comfort (and because it’s cheap). And I come from further than saaskwatch so I know what freezing pipes mean haha.

My point tho is - hp’s are not panacea in my use case.

Re: Harnessing America's heat pump moment

#304

Post by stavros »

CalRobert wrote: post #295
danielsju6 wrote: post #148

Maybe I have scar tissue from COVID prices but $20k to install a ductless heat pump vs. a $200 to throw a window A/C in or $700 for a portable heat pump. While I get that these heat pumps are better for the environment and much more efficient it's a last mile issue. The installers charge an arm and a leg and I'm not hurting enough to self install. I'm hoping the window heat pumps that just run off mains will be avail…

Why not pick up a few mini splits from Home Depot and slap them in yourself?

I think the better question here is "why can't I pay a fair price for an expert to do this for me?". What has happened to the market?

Re: Harnessing America's heat pump moment

#305

Post by adrianN »

ZeroGravitas wrote: post #301
neltnerb wrote: post #234

I've got to throw out an obvious explanation. A third of the country rents. Renters pay the utility bills. Landlords pay for appliance upgrades. Why would the landlord put any effort into upgrading appliances when the cost of not upgrading them is borne by the renters? I've never rented at a place where they didn't want to fix broken equipment with the cheapest possible replacement. And no renter would ever consider…

In some locations you can't rent out places without minimum energy efficiency ratings, which then leads to insulation and heat pumps getting installed.

Where is that?

Re: Harnessing America's heat pump moment

#306

Post by adrianN »

flakeoil wrote: post #302
edg5000 wrote: post #261

Earlier quoted context omitted.

They are efficient but do not have as high of an energy output as a smaller and cheaper gas furnaice. Apart from that, the water temperature is lower, so you need much larger radiators. Due to the lower energy output, you also need better insulation or a relatively massive heat pump. And the tech was not around 20 years ago (for reasons unknown to me).

The water temperature which you deliver to radiators are not defined by capacity of the heatpump, but how hot the radiators can be for safety/comfort reasons. If the radiators are too hot people could burn by touching them or stuff like platsic chairs would melt. Also the piping in the walls and floors cannot support too hot temperatures. The temp for water used in radiators 60-70C is easily achievable by an air-top-…

The heat pump runs with much better efficiency at <50 degrees.

Re: Harnessing America's heat pump moment

#307

Post by burnt-resistor »

Missed opportunity to discuss GSHPs and instead pushes electric HPs because it's a business blog masquerading as a .org to push product.

And also, contractors and maintenance shops push products that minimize their costs and maximize their profits. It's also why private equity owns effectively every high voltage motor capacitor manufacturer in the US and why those capacitors have such short lives now. It's not about minimizing TCO, it's about maximizing customer dependency upon service and parts without seeming there is any other choice balanced with the stochastic equilibrium of potentially more reliable alternatives threatening this "cottage" industry.

PS: clean your coils, change your air filters (without excessive MERV flow restriction), surge protect ECMs, and check your caps.

Re: Harnessing America's heat pump moment

#308

Post by kalleboo »

nine_k wrote: post #285
kalleboo wrote: post #222

Earlier quoted context omitted.

For comparison, I just bought a house here in Japan. Installed 6 minisplit heat pumps across various rooms in the house. All together it cost me 750,000 yen ($5,000) for the hardware and 90,000 yen ($600) for the install.

How much time did it take?

They arrived at 9 AM, was done by 2:30 PM

Re: Harnessing America's heat pump moment

#309

Post by pilingual »

Animats wrote: post #192

Everybody seems to agree that installation costs way too much. There's a few parts to this. Everything has to be carefully sized - power, pipe sizes, unit locations. You need to put a house's thermal profile (how much heat loss, how much air leak, how much thermal mass) along with the regional thermal profile into an engineering calculation which computes what you need. Thermographic inspections are a thing.[1] Usual…

This wouldn't work, unfortunately. A lot of insulation has a reflective layer yielding invalid readings from thermal imaging.

There are several other factors like air tightness which requires a blower door to measure and even the number of elbows in the duct system could have an effect. It's a surprisingly complex field. You wouldn't gain anything over a traditional home energy auditor.

The real opportunity is to scrap everything and rethink the system from scratch.

Re: Harnessing America's heat pump moment

#310

Post by upcoming-sesame »

kalleboo wrote: post #222
danielsju6 wrote: post #148

Maybe I have scar tissue from COVID prices but $20k to install a ductless heat pump vs. a $200 to throw a window A/C in or $700 for a portable heat pump. While I get that these heat pumps are better for the environment and much more efficient it's a last mile issue. The installers charge an arm and a leg and I'm not hurting enough to self install. I'm hoping the window heat pumps that just run off mains will be avail…

For comparison, I just bought a house here in Japan. Installed 6 minisplit heat pumps across various rooms in the house. All together it cost me 750,000 yen ($5,000) for the hardware and 90,000 yen ($600) for the install.

Do you mean 6 A/C units ? I. e. 6 outdoor and indoor units

regardless, this is incredibly cheap

Post reply on HN