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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

#311

Post by jefftk »

david422 wrote: post #265
exe34 wrote: post #239

Earlier quoted context omitted.

Is there a reason heat pumps use electricity? I would have thought the same approach would work with gas - you only need to burn a fraction of the gas to drive the "fridge" backwards?

I think you are back to where you started. If it was cheaper to use gas to run a heat pump then everybody would just run generators in their houses off of gas instead of using electrical lines.

In MA this actually does work at first glance: a 23% efficient Generac 7171 is rated for 9kW at full output on natural gas, and uses 127 ft3/hr (1.37 therms). This is $0.30/kWh at $2/therm, compared to the $0.323/kWh I pay the power company. If you were doing this for real you'd put in the work to find something more efficient than this unit, which would then be enough to make up for the cost of the generator and the maintenance.

Except it's not legal to do this, and even if it were there'd be a lot of hassle.

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

#312

Post by jefftk »

bluGill wrote: post #290
david422 wrote: post #265

Earlier quoted context omitted.

I think you are back to where you started. If it was cheaper to use gas to run a heat pump then everybody would just run generators in their houses off of gas instead of using electrical lines.

That has been proposed. Well the proposal was to run a small engine powering a generator, then you cool the engine to heat the house, while the electric is sold (or otherwise powers the house). However modern gas furnaces are > 90% efficient and it is hard to get an engine that efficient for heat (remember the engine will be running indoors so it needs to not fill the house with noise of CO). I think no matter how yo…

> I think no matter how you look at it, you can't make this system more efficient than just using the furnace to generate heat without the engine.

I don't think that's right: look at micro-CHP (Combined Heat and Power) systems: they run an engine to generate electricity, and then capture the heat for heating. I don't think you can get them for residential in the US though.

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

#313

Post by 1minusp »

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.

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

#314

Post by wongarsu »

what_ever wrote: post #275
gnicholas wrote: post #243

Earlier quoted context omitted.

> 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?

Is net metering a subsidy?

If few people use net metering it's kind of fair. Your solar installation generates electricity, any excess gets delivered to your neighbors. The electricity is providing the infrastructure for that without making any money on that specific transaction (it gets deducted from your meter and added to your neighbors' meter), but that's easy enough to account for in base fees.

The issues start if too many people do net metering. Imagine everyone has a solar roof and reaches net-zero electricity. You can still maintain the infrastructure with base fees, but the electricity company still has to run power plants in the morning and evening when demand outstrips solar supply, and for baseload in the night. And during the day there's now an oversupply of electricity that they somehow have to sell.

In commercial electricity generation many countries have a kind of spot market for electricity, where prices are determined by demand (down to the minute) and available supply. Prices can go close to zero if lots of solar and wind capacity is available, or far above the price charged to consumer for capacity to cover the evening peak. If we changed consumer prices to more accurately reflected this "true" market price (plus markup for the grid operator), with prices changing by the minute, net metering would be pretty fair. But so far there's little desire to dump all that complexity on regular consumers.

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

#315

Post by SECProto »

gnicholas wrote: post #295
SECProto wrote: post #286

Earlier quoted context omitted.

All electricity generation throughout the US is subsidized in various ways already - eg low interest loans for new generation capacity, programs for low income earners, not (or not effectively) charging for carbon and methane emissions, low fuel taxes on sources used for electricity generation. The "subsidies" you list help make a desirable energy source compete on a more level playing field - matching benefits that…

My understanding is that when utilities buy energy from solar farms, they do so based on the demand and available supply, meaning that solar farms get paid more or less depending on these factors. But with net metering for residential solar installations, utilities are buying independent of supply/demand, which gives the residents a subsidy even vis-a-vis other solar producers. I understand that all kinds of energy p…

There are all kinds of complications - commercial solar isn't dispatchable so it does tend to get lower rates than most other sources. In my jurisdiction residential (net metering) customers are only allowed to install a certain numbers of panels - corresponding with household energy consumption and assumed production levels (i.e. your monthly bill will never be negative - at lowest you'll be paying distribution charges and 0 for consumption). With low levels of residential solar installation, locally installed panels can help balance the grid as it is consumed on distribution lines and doesnt need transmission lines (conversely, high levels can unbalance the grid).

> if net metering lets residential solar owners get paid more for the energy they produce than solar farms would be paid, I don't see how that's anything but a subsidy.

Paying them nothing would be even more unfair (and that's the only option available where I am at least - net metering or no household generation)

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

#316

Post by bluGill »

Mountain_Skies wrote: post #32
danans wrote: post #8

A big issue right now is the oversizing of heat pumps by HVAC contractors who are used to sizing gas furnaces using very simple btu/hr/sqft calculations. A contractor should do some kind of heating need analysis, at the least by studying old utility bills, and ideally by doing a Manual J heat loss calculation for the house. But almost none of them do that. There are some startups attempting to handle these design ste…

Other than higher cost for the heat pump unit, are there any other issues with having one that's oversized for heating? My understanding is that for cooling, having one that is oversized can be a problem because of humidity issues, which also makes me wonder what can be done if a space has an imbalance between the size needed for cooling versus what it needs for heating.

No there is not IF the heat pump is variable speed/flow. Many modern ones are, but most old ones are not, and it is really hard to tell if a new one is. In fact you want one oversized as if it is the correct size for cooling it cannot make enough heat when it is cold (it can make heat, just not enough)

If you get a normal single speed heat pump see the other reply - there are significant downsides.

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

#317

Post by jdeibele »

oooyay wrote: post #254
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…

Yeah, I made this mistake this year. I pumped $20k into a heat pump system, coming from what used to be Natural Gas. I wasn't given any kind of relief because I live in Oregon where most relief is income based. Then at the beginning of the year PGE announced a 20% rate hike. My house is covered in trees, so solar isn't really an option. I really regretted my decision once I got a $300-$400 bill for heating three mont…

I'm moving from Portland to McMinnville in a couple of months. Price of kwh goes from $.1945/kwh to about $.0720. I've noticed that McMinnville Water & Light doesn't help pay for EV connections, etc. compared to Portland General Electric but at almost 1/3rd the cost, they probably don't need to.

MW&L is community-owned, PGE is traded on the NYSE. They both buy a ton of hydro from the Bonneville Power Administration.

https://findenergy.com/providers/mcminnville-water-and-light... gives an average. Actual per kwh rate is cheaper but there's a $16.10 customer charge to have an account. https://www.mc-power.com/wordpress/wp-content/uploads/pdf/ra...

https://portlandgeneral.com/about/info/pricing-plans

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

#318

Post by ghufran_syed »

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…

I’m in Northern california, I just got a heat pump installed by these guys: https://www.heliosclimate.io/ - a YC company btw, for those who think they just fund consumer apps :)

Overall it was a great experience, there were some minor issues immediately after installation that got dealt with quickly and efficiently. I think the list price was similar to what you were quoted, but in northern california (menlo park, peninsula clean energy) there were around $5000 of grants/tax incentives, and an interest free loan from pce for the rest, over 5 years meaning our monthly repayment should be about equal to the reduction in our gas bill.

We already had solar and batteries, otherwise I would NOT want to put myself at the mercy of PGE and their crazy electricity rates. But as they reduce the payment rates for solar electricity, the heat pump becomes a better deal.

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

#319

Post by sokoloff »

jefftk wrote: post #306
xutopia wrote: post #303

Earlier quoted context omitted.

I'm in Canada and we have heat pumps with secondary heat sources for when it gets really cold. Mine is with gas.

These sorts of programs generally require you to disable your existing heating system, and don't allow you to run it only in warmer weather. Ex, Massachusetts: https://www.masssave.com/-/media/Files/PDFs/Save/Residential...

Note that's for the whole home $10K rebate only. For the per-ton rebate, you can leave the existing fossil fueled appliance installed and connected. (It's also new for 2024; the 2023 rules allowed you to leave the appliance in to be used for supplemental heat during extreme cold or during an equipment outage. https://www.masssave.com/-/media/Files/PDFs/Save/Residential... )

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

#320

Post by zbrozek »

giobox wrote: post #292
bluGill wrote: post #280

Earlier quoted context omitted.

All modern furnaces I've seen take #2 - use air from outside. Despite that they can get to 99% efficient. It doesn't take much energy to heat up that cold air.

My experience in the US at least is that its not uncommon for the furnace air intake to draw air from inside the house (my last two homes in PNW as one example).

California resident here. Both of my last two places with gas furnaces combust unconditioned air.
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