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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

#671

Post by fnbr »

Scoundreller wrote: post #503
fnbr wrote: post #350

Earlier quoted context omitted.

Yup, me too. And with my Nest thermostat, I can manually configure the crossover point. I did so at the economic balance point (where the heat pump is cheaper than my gas furnace).

Is there any capability in having a "smart" economic balance point? IE: Accounts for time of day/market pricing of kwh? I guess there needs to be occasional reprogramming of gas prices?

No, unfortunately. But my gas/electricity is fixed price, so it doesn’t matter. I’m sure this will be coming as heat pumps get more common. It’s a pretty easy calculation to do.

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

#672

Post by simonjgreen »

For those complaining of the cost of electricity vs natural gas, consider if the cost matters when you are comparing to burning something you shouldn’t be burning in the first place. It’s a bit like complaining it’s cheaper to steal food from a store instead of pay for it.

And I know electricity production is not renewable everywhere in the world yet, but at least it’s on a path and possible. Burning natural gas doesn’t have that course.

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

#673

Post by jtdev »

saalweachter wrote: post #667
pie_flavor wrote: post #664

No. As technologically cool as electrification is, the power occasionally goes out. When that happens, the heat should not. Not everyone has access to a generator, but gas lines don't need that. Same reason we don't electrify toilet flushing despite potential water savings.

Oil burners and gas furnaces also use electricity, to modulate the fire and circulate the heat. The only thing they don't use electricity for is generating the heat. In a power outage it just sits there, not able to turn on.

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

#674

Post by jtdev »

vundercind wrote: post #30
mikeyouse wrote: post #23

Earlier quoted context omitted.

> Uh, you still need a furnace (though it could be electric) if you live somewhere that ever really gets cold, right? For now - and only in part of the country. Most of the newest models can output 100% of their rating down to something like -5ºF -- they're easy enough to oversize as well, so if your 99% heating load is e.g. 48,000BTU, a 60,000BTU heat pump that's only outputting 80% of rated BTUs due to the extreme…

I’d say -15°F or lower is something you need to design for at least into the light-blue area on this map: http://4.bp.blogspot.com/-tdK_AMaZ9pg/Vb51WrvPDhI/AAAAAAAAD5... Which is quite a lot of the country. Light blue is a typical Winter low point in the -10°F to 0°F, which means you will see -15°F or lower often enough to worry about it.

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

#675

Post by hedora »

iraqmtpizza wrote: post #596
Retric wrote: post #349

Earlier quoted context omitted.

In the continental US you get ~2x the heat from burning natural gas in a combined cycle turbine to run a heat pump than you would from using a high efficiency gas furnace. The market price of electricity vs gas varies quite a bit through time and various distortions of the market. Currently gas is cheap, but you want to compare historical averages when buying something that lasts 15+ years not simply look at current…

I would like to see HN recommend looking at historical averages before buying an EV.

People have; it's a obvious win. There are sites that do this for your zip code correctly, but an efficient EV gets 4 miles / kWH. An efficient hybrid gets under 60 MPG.

California's insanely high electricity rates are about $0.15 / kWh, so the energy costs $0.0375 per mile.

Gas has hovered around $4 / gallon or higher for a long time, giving a fuel cost of $0.0666 per mile.

Big energy guzzling EVs get about 2 miles / kWh, for $0.075 per mile, and gas guzzlers easily get below 15 MPG, or $0.26 per mile.

You'd have to go back to the days of $1 / gallon gas (mid 1990's?) and ignore inflation / lower electricity costs back then to conclude large ICE cars have competitive fuel costs. You'd "only" need to go back to $2 gas for the energy efficient hybrids to be competitive.

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

#676

Post by hedora »

gnicholas wrote: post #610
bagels wrote: post #512

Earlier quoted context omitted.

Previously: Spend $60k to save $200/month Now: Spend $60k to save $100/month Break even would then be much further in to the future. Solar is a large capital expenditure, and this change reduces the return on that investment.

Can you explain how the income-based fee results in lower savings? It is a fixed fee that applies whether or not you have solar. To be clear, I think the income-based fee is a bad idea, but I just don't think it changes the calculus on installing solar. I have also had conversations about this specific question with a friend who has a PhD in urban planning, lives in CA, and is in the process of installing solar panel…

Income based pricing encourages people to go off grid.

The upfront cost of doing that with a propane generator is about a half that of a battery + solar system (it's about a third if you go with battery + solar + generator, which is more comparable to a grid connection).

However, the maintenance and fuel costs of the generator mean that the solar will be much cheaper (and quieter!) to operate.

If the income based pricing is $100 / month, and the net energy / base connection cost is $0 / month (assuming an exactly sized solar system), then it'll take about 200 months for the generator to pay itself off. That's 16 years, which is a bit longer than the system will last, though replacing a generator costs about half what I've assumed above.

So, there's a pretty low upper limit to the amount they can screw with these fees before it's economically (though not necessarily environmentally) rational thing for individuals to just cut the cord and let the power grid death spiral.

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

#677

Post by naijaboiler »

valenterry wrote: post #564
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.

Modern great heatpumps, installed correctly, are rather between 5 and 7 in terms of COP. Also, even the best gas heating systems only achieve 90% efficiency. In other words, it either be very very very cold in your area, or you have to screw up the installation before gas has lower running(!) costs. Besides that, a gas power plant easily achieves 33% of efficiency for generating electricity from gas, rather 50% for t…

I dunno. My mom’s heating bills in Indiana using heat pumps with auxiliary electric heaters was >$700 month at electricity costing 11c/kwh. I live in Massachusetts where my electricity cost 33c/kwh. So if I used my mom’s heater to heat a house of similar size, my heating bill will be $2k/month. My heating gas bill is under 120/month.

I understand a bulk of that cost comes from the aux resistive electric heater. But for really cold places, that’s needed when the heat pump can’t keep up or you need to rapidly warm the house.

As is, we are still quite far from heat pumps being cost efficient as gas for places that get really cold

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

#678

Post by naijaboiler »

Retric wrote: post #415
Aloha wrote: post #372

Earlier quoted context omitted.

I don't think your math adds up. Combined cycle is like at most 70% efficient, subtract 10% of distribution, you end up with 60%. At 50f my 5T heat pump takes 6.6 kWh to generate 50,000 BTU. 6 kWh of energy takes 71cf of gas to make - accounting for transmission and generation losses. 71cf of gas will make 71,000 BTU of heat, assuming an 80% efficiency furnace, that comes out to 56,000 BTU usable. Yes a heat pump wil…

Replace your heat pump? People installing new heat pumps are going to see much higher efficiency. 50,000 BTU = 5.27528 * 10 ^ 7 J = 14.6 kWh / 6.6 kWh = COP of 2.2 at 50f which is absolutely terrible. Modern heat pumps should have a COP around 4 at those temperatures and 3 near freezing. Also, “Subtracting 10%” would mean your grid losses are 17%. “annual electricity transmission and distribution (T&D) losses average…

So I have to spend 10k on a new heater every 10 years just to keep up

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

#679

Post by kenmacd »

lsllc wrote: post #525
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…

The big issue in New England is that heat pumps (ASHP or GSHP) are only really possible for new builds. Most existing homes will likely be forced hot water and there isn't any heat pump out there that will produce water hot enough (e.g. 185F), so your only option is to retrofit ducting (or go mini-split but then you need one in every room). Even homes with ducted AC, it's likely they are sized for cooling only, not h…

> here isn't any heat pump out there that will produce water hot enough (e.g. 185F)

For 185:

https://www.arcticheatpumps.com/high-temperature-heat-pump.h...

Or much more common, if you can deal with 176F, the SANCO2 ones will generate that down to -20F.

The hydronic temperatures you're talking about are only required if you have to stick with the existing radiators. They make radiators with little fans that work at lower temperatures, or larger panel radiators. There's lots of options for lower temperature forced hot water.

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

#680

Post by turing_complete »

simonjgreen wrote: post #672

For those complaining of the cost of electricity vs natural gas, consider if the cost matters when you are comparing to burning something you shouldn’t be burning in the first place. It’s a bit like complaining it’s cheaper to steal food from a store instead of pay for it. And I know electricity production is not renewable everywhere in the world yet, but at least it’s on a path and possible. Burning natural gas does…

Terrible analogy
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