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Nine US states are teaming up to accelerate the adoption of heat pumps

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Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#441

Post by cde-v »

newZWhoDis wrote: post #364
david422 wrote: post #270

Earlier quoted context omitted.

I use solar, but using heat pumps and an electric car uses maybe 3x more electricity than my roof can produce.

Higher efficiency panels + vertical panels would help. Most houses have decent south-facing walls. Ground mount is also an option in many places.

20kW ground mount array in NH produces twice as much as we need for our 4 heat pumps heating 3000 sqft. Went into the last two winters expecting to deplete our summer credits with the power company but we have only used about 1/6th of it.

Definitely doable.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#442

Post by jcalvinowens »

I have NEM2 solar, so obviously a heat pump is a big win. But I'm convinced the heat pump I installed a couple years ago would save money even without the solar:

I pay $0.30-$0.40/KWh for electricity, and $0.08/KWh for natural gas ($2.35/therm) *.

My heat pump has a COP of 3.62 when the outdoor temperature is 47F: it uses 1KWh of electricity to move 3.62KWh of heat into my home. The old gas furnace was 80% efficient ("AFUE"): it used 1KWh of gas to dump 0.8KWh of heat into my home.

So, at 47F, as long as the ratio between the cost of electricity and natural gas is less than 4.53x (3.62 / 0.8), the heat pump saves me money. In my case, this means I save money when electricity costs less than $0.37/KWh, which it does almost all the time.

At $0.30/KWh-electricity, I effectively pay $0.083/KWh-heat with the heat pump, a 17% total heating cost savings over the $0.10/KWh-heat the old gas furnace cost.

Heat pumps do become less efficient as it gets colder outside: at an outdoor temperature of 17F, my heat pump COP is only 2.44, which would cost more than my old furnace ($0.123/KWh-heat vs $0.10/KWh-heat).

Extrapolating linearly between the 17F and 47F COPs from the manual (it only gives those two points; this isn't strictly correct, but close enough), the temperature below which my heat pump starts to cost me more money than my old gas furnace is roughly 30F (3.0 COP). In the decade I've lived in the bay area, I've never seen it get that cold, which is why this is such a perfect climate for heat pumps.

* These numbers are from August 2022

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#443

Post by crazygringo »

gertlex wrote: post #140
TheBlight wrote: post #94

Earlier quoted context omitted.

How well do they function? Do they provide nice consistent heat? How's the noise? Sorry to clog up HN with a random request of a product quality review but I'm in the market right now to replace my furnace as well. Thanks.

One anecdote I've seen is that the right way to run them is to maintain a near-steady-state temperature in the house, including overnight. I'm not sure if that's maybe a bit extreme and just how they suggest use to non-savvy home-owners, but it makes sense... They're not going to blast out heat to raise the house temperature 10 degrees in an hour in the morning. Spreading heat-increase over several hours is more feas…

You don't need to run it overnight. But I do set a timer for mine to turn back on an hour before I get up. Because exactly -- it's not blasting hot air, it's merely circulating warm air. An hour beforehand works fine for mine though.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#444

Post by PaulDavisThe1st »

sokoloff wrote: post #308
what_ever wrote: post #275

Earlier quoted context omitted.

Is net metering a subsidy?

Absolutely. If a customer is permitted to buy as much electricity as they want at a fixed price while also being able to sell as much as they can at a different time at a fixed price, it seems like there's an obvious subsidy happening anytime they sell electricity at other than when the wholesale price is the highest or buy other than when the wholesale price is lowest. (In areas with an excess of solar generation ca…

But until the relevant grid is saturated with solar generation, surely the surplus just needs to be moved around.

And if the grid itself is saturated, that means it isn't big enough.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#445

Post by alistairSH »

epistasis wrote: post #95
readingnews wrote: post #86

I just replaced a furnace... everyone I called for a quote would not touch a heat pump with a 20foot pole, or they wanted prices that were 2X what a separate furnace and AC would cost to install. It was very strange. This is the second home where I had this experience.. basically, they really did not want to install it. I ended up going with gas as no local person would install/warranty a heat pump, or, it was priced…

Your experience is extremely common. Residential HVAC contractors tend to be extremely conservative, and don't adopt new technologies quickly, or even attempt to understand them. I had some flexibility in time in replacing my 50 year old gas furnace, so I was able to call about 8 contractors before I finally found one who was comfortable with the tech and wanted to do it.

But heat pumps aren’t new. And aren’t much more complicated to install than a stand-alone AC. And certainly less complicated and less labor (overall) than than AC+furnace.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#446

Post by interroboink »

antisthenes wrote: post #396
nostromo wrote: post #114

I have mixed feelings about our heat pump system. Yes, it's efficient. But it breaks about once every other year. Last winter the compressor circuit board malfunctioned and cost $5k to fix. Two years ago it was another issue entirely. All of our savings have been lost to service calls. I'm not super price sensitive, but it's still a pain when the heat goes out in the middle of winter and all the service techs are boo…

> Last winter the compressor circuit board malfunctioned and cost $5k to fix. Ok, so it sounds like you got scammed. HVAC circuit boards cost $100. > Two years ago it was another issue entirely. Which was? > All of our savings have been lost to service calls. I'm not super price sensitive Yeah, obviously, if you're willing to spend $5k on a service call. > If we ever have to replace it, we're going to have to rip ope…

> HVAC circuit boards cost $100.

This very much depends on the brand and the board, no?

A quick search for the brand the OP mentioned (Daikin) shows some boards easily in the $1000 range.

Just one example: https://airconditionersrus.com/en/components-parts/2423-daik...

I don't know the details of OP's situation, but I'm not sure what makes you say such things so confidently.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#447

Post by turtlebits »

aqfamnzc wrote: post #246
turtlebits wrote: post #218

Earlier quoted context omitted.

Yes, HVAC contractors in the US massively overcharge. I saved ~ 10k doing the install myself. The equipment is inexpensive, labor can be upwards of 2x equipment cost.

Do you feel like the number of invisible footguns was manageable? That's always my concern with diy trades stuff, the things that seem fine at install but come back to bite you 6mo later.

No invisible footguns, just a bit of anxiety releasing refrigerant and hoping my lineset connections don't leak. Theres only a preset amount of refrigerant, it dissipates into the air and theres no easy way to refill it.

That said, some will inevitably leak out (ie. while disconnecting manifold gauge set) but no big deal. I've done four installs and nothing catastrophic.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#448

Post by vondur »

gnicholas wrote: post #243
bagels wrote: post #214

Earlier quoted context omitted.

Right, the heat pump will reduce energy use to maybe 1/3 of a gas furnace, but natural gas is something like 6x cheaper for the same amount of energy, so it is an expensive folly. If California is serious about this, they need to reign in the utilities to reduce prices and or stop the attacks on solar installation.

> stop the attacks on solar installation I've not heard of any attacks, just reductions in subsidies (tax credits, net metering). Can you share what you're referring to?

Basically, to get subsidies, you need to install a battery storage system with a solar installation. This can be quite a bit more expensive than the solar alone. (worth it if possible, adds a backup in case of a power outage too)

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#449

Post by lelandbatey »

GloriousKoji wrote: post #193
burkaman wrote: post #144

Earlier quoted context omitted.

> It's now more expensive to fuel a vehicle with electricity than gas This is very hard to believe, what are you paying for electricity? California gas prices are also way above the national average at the moment. Here's a per-state comparison from last year, I'm sure it's a bit out of date but I doubt things have completed flipped in a single year: https://energyinnovation.org/2023/07/27/ev-fill-up-savings/

I live in the Bay Area California and get electricity from PG&E. I use a minimal amount of electricity and I paid 43 cents/kWh last month. Gas from Costco is $4/gal right now. I have a plugin-hybrid which does 4miles/kwh and 45mpg or in terms of money: 9.3miles/$ on electricity and 11.25gas-miles/$ on gasoline. But maybe you don't actually care about fuel efficiency, then you have an argument that it's cheaper to fue…

> I paid 43 cents/kWh last month

Whoooooa ok that makes more sense why folks are complaining; I paid 13 cents/kWh last month, less than 1/3 of what you're talking about.

Note for others, paying $0.45/kWh is highly unusual for the US as a whole; see the US Gov published stats on average electricity prices by region which puts the average at ~$0.17/kWh: https://www.bls.gov/regions/midwest/data/averageenergyprices...

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#450

Post by PaulDavisThe1st »

1minusp wrote: post #313
mdasen wrote: post #174

One of the big problems with heat pumps in New England is that our electricity costs 1.7x the US average ( https://www.eia.gov/electricity/monthly/epm_table_grapher.ph... ). If you're in the South, a heat pump makes perfect sense. You're going to want AC anyway and it'll be way more efficient and save a ton of money when you want heat. In most of the country, even if it gets cold your electricity prices are still a t…

Large drilling costs from where I am in the south due to ground being mostly (lime?)stone: makes it cost-infeasbile. Other areas might have it easier though.

It can vary over the micro-scale. Where I live in NM, we could go down very deep and never hit rock, because we're sitting on the soft sandy soil(ish) alluvial deposits at the bottom of large (20 mile diameter) basin. But neighbors who live less than 1 mile away are sitting on metamorphic rock just inches below the surface.
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