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Harnessing America's heat pump moment

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Re: Harnessing America's heat pump moment

#331

Post by bluGill »

thelastgallon wrote: post #266
caminante wrote: post #249

Earlier quoted context omitted.

I'm jealous of the learning and hobby project. Though, the returns are (edit: "not great") if the figures above INCLUDE net metering revenues. Heatpump = Negative IRR until y8 Solar = Negative IRR until y16 Heatpump + Solar = 0 NPV through y25 | 8% discount rate

I'm jealous of your financial learnings. However, your model is not accurate as it doesn't factor in the 4 degree improvement in comfort and indoor pollution from propane furnaces: Propane furnaces can cause indoor pollution through the release of pollutants like carbon monoxide (CO), nitrogen dioxide (\(NO_{2}\)), and benzene, which are byproducts of combustion. It also doesn't include the negative externalities bec…

Indoor propane furnaces exhaust outdoors in most cases. Space heaters that exhaust indoors are rare - more used for garrage heat than house. If you use them of course actount for it, but most are not.

Re: Harnessing America's heat pump moment

#332

Post by bluGill »

thelastgallon wrote: post #276
glxxyz wrote: post #256

Earlier quoted context omitted.

Yes the people selling solar systems all factor in aggressive future electricity increases, it's best to also see how it looks with more conservative rate increases. By my calculation in a reply above with the interest free solar loan it's an 8% return over 14.3 years.

Residential electricity rates have risen fast across the US—more than 30 percent on average since 2020 and almost double the rate of inflation: https://www.wired.com/story/power-bills-in-the-us-are-soarin...

Very regional though - my rates have not gone up.

Re: Harnessing America's heat pump moment

#333

Post by bluGill »

mikepurvis wrote: post #269
chongli wrote: post #212

Earlier quoted context omitted.

There’s another alternative: a mini-split. Larger than a window unit, with a refrigerant lines you run yourself but with the actual refrigerant pre-charged inside the unit, so you don’t need to handle it yourself (which usually requires a license). Mini-splits tend to be much cheaper than full installations.

I looked into the precharged DIY option and the lengths just didn’t work out for what I needed in my space. I ended up paying a licensed installer C$12k to put in a three head system (two conventional, one ducted), and then a separate guy $5k to do the ducting for the bedroom level. It would have been nice to do it as one, but the HVAC firm didn’t want to get their hands dirty with my wacky ducting plan, and the duct…

The systems where you need to get a epa license are cheaper. The license is appearently easy to get.

Re: Harnessing America's heat pump moment

#334

Post by bluGill »

adwn wrote: post #246
jofla_net wrote: post #239

Earlier quoted context omitted.

Its most simply summed up as what I call the tradesman's protection racket. On one side of the coin you have any moron, calling himself a repair man which can and does end in disastrous jobs which can be unsafe. This though has much lower pricing. The flip side is, basically a protection racket where suppliers only sell to you if you have a 'loicense' and the hurdles required to become said VIP are so high, giving yo…

Have you considered that the second path you outlined, "giving your body to a master tradesman to get a piece of paper over many years" (in the figurative sense), is in general a necessary prerequisite to avoid the first path of any moron being allowed to "[call] himself a repair man which can and does end in disastrous jobs" ? > I wish I could live in a world somewhere in the middle […] This world would just be a mi…

I've done a lot of that type of work myself. It isn't hard to learn how to do it right from books - and I have passed inspection reports to prove it. I've also seen those professionals do a terrible job - to the point inspectors admitted to hurrying my job because they knew the next would be a mess.

Re: Harnessing America's heat pump moment

#335

Post by upcoming-sesame »

zemvpferreira wrote: post #320
upcoming-sesame wrote: post #310

Earlier quoted context omitted.

Do you mean 6 A/C units ? I. e. 6 outdoor and indoor units regardless, this is incredibly cheap

It’s very normal here in Portugal. If you looked carefully and weren’t picky about the brands, you could have 6 mini-splits installed for $3000 all-in.

Parent mentioned $600 for the install. I live in Portugal as well, paid around $500 for ~one~ mini split A/C install

Re: Harnessing America's heat pump moment

#336

Post by maxerickson »

relaxing wrote: post #228
smileysteve wrote: post #156

Earlier quoted context omitted.

Re #2. Tuning a heat pump vs resistive heat is a much tougher game than it should be. In a moderate climate, I use my ecobee to ensure aux heat doesn't come on until it's below freezing, and it should only come on if something has gone wrong at that point too. Unfortunately, many thermostats by default will use resistive heat in relatively normal scenarios, of worse, when you've programmed home and away times intende…

In a moderate climate you should have no need for resistive heat. Why isn’t running the heat pump alone enough?

They are saying that badly configured controls often run the resistive heat when it isn't needed.

Re: Harnessing America's heat pump moment

#337

Post by chongli »

dzhiurgis wrote: post #303
chongli wrote: post #235

Earlier quoted context omitted.

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.

Heat pumps are not inherently expensive though. It depends on how competitive (or not) your HVAC industry is. Sounds like New Zealand has issues with this (probably due to being a small market).

Re: Harnessing America's heat pump moment

#338

Post by Spivak »

thelastgallon wrote: post #276
glxxyz wrote: post #256

Earlier quoted context omitted.

Yes the people selling solar systems all factor in aggressive future electricity increases, it's best to also see how it looks with more conservative rate increases. By my calculation in a reply above with the interest free solar loan it's an 8% return over 14.3 years.

Residential electricity rates have risen fast across the US—more than 30 percent on average since 2020 and almost double the rate of inflation: https://www.wired.com/story/power-bills-in-the-us-are-soarin...

It will be interesting to see if this will make natural gas a more attractive source of residential heating as the price has remained relatively stable over the past 20 years.

The push for electrification seems like it relies on us metaphorically drowning in excess cheap electricity and want somewhere for it to go but right now the opposite it happening.

Re: Harnessing America's heat pump moment

#339

Post by eldaisfish »

ssl-3 wrote: post #245
eldaisfish wrote: post #195

Earlier quoted context omitted.

> They use the same amount of electricity whether heating or cooling This is completely wrong. The amount of power depends on the temperature delta. When cooling, you are typically not cooling your home to 30 degrees Celsius below the outdoor temperature. However, when heating, you are typically heating your home to around 20 degrees above outdoor temperature. Heating consumes more power than cooling.

It is approximately correct as long as the temperature deltas are approximately the same for heating vs cooling. (And as long as we're dispelling generalizations: Those deltas do vary wildly based on local climate, such that they're impossible to generalize and typify. For instance: The city of Saint Paul, Minnesota [USA] has a very different climate compared to the city of São Paulo in Brazil, with accordingly-diffe…

Well, in that case, you don’t need a heat pump. You need a sweater and an AC.

The real advantage of heat pumps is in displacing high cost fuels.

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