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

I got a heat pump and my energy bill went up

heatpumped.org

Post reply on HN
Print view View original

61–70 of 156 posts

Re: I got a heat pump and my energy bill went up

#61

Post by Yeul »

Kim_Bruning wrote: post #45
nottorp wrote: post #39

Earlier quoted context omitted.

Agreed, but you only tend to accept that when the other needs in that famous pyramid are taken care of. Regulation that increases cost of living is only going to cause resentment and we already see where that leads to. Can't do it with feel good statements, you need the authorities to support/push towards cheaper electricity. Like the Denmark poster said elsewhere on this thread. Is this going to happen globally? I s…

China is pushing hard; EU is pushing less hard but a little; only the US (says) they're going to lag behind these next few years.

America has vast natural gas reserves there's no need to invest.

If your country has to import oil and gas there is a financial reason to change.

Re: I got a heat pump and my energy bill went up

#62

Post by skyyler »

glimshe wrote: post #51
tommiegannert wrote: post #28

Transparency is great, but let's not forget that the point of switching to electricity is to be able to use renewables. We only have one nice planet to live on, and there are others who want to keep being able to live comfortably on it, I've heard. Oil/gas is a potent drug that is difficult to vane off of. (Arguably solar/battery has the same problem as oil: let's dig and refine stuff from the ground, and not care ab…

It's not only potent, but fantastically cost-effective. There is a reason it's popular, or so I've heard.

It's not so cost effective when you include the future costs.

But like a payday loan, it's hard for most of us to think about those future costs until they're being collected.

Re: I got a heat pump and my energy bill went up

#63

Post by dns_snek »

rayiner wrote: post #10

I don’t know where this person is, but electricity is wildly expensive in many places. On a cold day, a good heat pump might give you say a COP of 2. So with 5 kW, you get out 10 kW of heat, or 35,000 BTU/hour. In say MA, at $0.25 per kWh retail, that’s $1.25/hour. In Boston, natural gas costs $1.5/therm, which is 100,000 BTUs. With a 96% efficient condensing boiler, you’re looking at $0.55/hour for the same 35,000 B…

You really need to be calculating costs based on seasonal performance (SCOP) which is going to depend on your area. In my climate the worst case COP is around 2, but the seasonal performance of an air-to-water heat pump would be between 3.5 and 5, depending on various factors.

Granted it doesn't make a difference in your example because your gas is cheap at $0.05/kWh, but for me (EU), the price for natural gas would be around $0.11/kWh while electricity is around $0.25/kWh.

Re: I got a heat pump and my energy bill went up

#64

Post by rlpb »

tommiegannert wrote: post #28

Transparency is great, but let's not forget that the point of switching to electricity is to be able to use renewables. We only have one nice planet to live on, and there are others who want to keep being able to live comfortably on it, I've heard. Oil/gas is a potent drug that is difficult to vane off of. (Arguably solar/battery has the same problem as oil: let's dig and refine stuff from the ground, and not care ab…

> let's not forget that the point of switching to electricity is to be able to use renewables

Here in the UK, natural gas is used to provide electricity[1], so switching to a heat pump right now isn't likely to help with the environment and (because gas is vastly cheaper per unit energy) nor the utility bill. You might as well spend the capex on the insulation upgrades required for a heat pump anyway, but then stay on gas. The bottleneck seems to be on us weaning ourselves off gas for electricity first.

[1] 53% natural gas during the recent cold snap, and only 16% renewables, according to https://news.sky.com/story/britains-gas-storage-levels-conce...

Re: I got a heat pump and my energy bill went up

#65

Post by BenjiWiebe »

KptMarchewa wrote: post #53
Kim_Bruning wrote: post #52

Earlier quoted context omitted.

Ah, so ultimately the author did end up paying less. The problem was they were on the wrong plan. And the optimization problem at this point in time is that -ideally- you want to have some amount of excess generation on your solar panels, then time shift that with batteries to a point in time when power is more expensive, and have some amount of excess capacity in batteries so you can also sell that power; versus the…

>And the optimization problem at this point in time is that -ideally- you want to have some amount of excess generation on your solar panels, then time shift that with batteries to a point in time when power is more expensive, and have some amount of excess capacity in batteries so you can also sell that power; versus the (amortized) cost of that extra capacity; and/or what will actually fit on your roof. Yep, that's…

7 hours of sun in a month? How do you survive? I think I'd go crazy.

Re: I got a heat pump and my energy bill went up

#66

Post by tatersolid »

seanmcdirmid wrote: post #58
nottorp wrote: post #35

Earlier quoted context omitted.

> while electricity is also normally expensive, if you have electrical heating you're excempt from paying taxes on electricity usage above 4000 kWh per year :) So it can be done with state subsidies, but worldwide even the one time bonuses for EVs are being canceled. States aren't likely to give up on even more revenue.

It’s not a subsidy, but a hold back from taxation. It’s usually in these country’s national security interests, let alone environmental interest, to push away from gas and oil given that they are often imported from hostile nations. America doesn’t really have that same problem, but Denmark and China do.

> It’s not a subsidy, but a hold back from taxation.

These are exactly the same thing in the end unless a subsidies were to exceed tax revenue.

Re: I got a heat pump and my energy bill went up

#67

Post by r_klancer »

rayiner wrote: post #10

I don’t know where this person is, but electricity is wildly expensive in many places. On a cold day, a good heat pump might give you say a COP of 2. So with 5 kW, you get out 10 kW of heat, or 35,000 BTU/hour. In say MA, at $0.25 per kWh retail, that’s $1.25/hour. In Boston, natural gas costs $1.5/therm, which is 100,000 BTUs. With a 96% efficient condensing boiler, you’re looking at $0.55/hour for the same 35,000 B…

After I installed a high-COP, cold-climate heat pump in my Boston area house in 2020, I figured the wintertime running cost was about half again the cost of gas heat. However, the cost was about the same as that of running the somewhat ancient oil furnace the house came with.

Electricity prices in MA are high and are controlled by the marginal cost of gas to run generators, even though we have a significant fraction of renewable, hydro, and nuclear generation. Gas prices are also high because we're at the far end of the east coast natural gas pipeline network.

It's interesting to think about the whole chain -- burning gas in a high efficiency condensing furnace at home approaches 100% efficiency of conversion from chemical to heat energy.

Whereas utility generators that convert heat to electricity are upper bounded by the second law to ~60% efficiency, and then you have transmission losses on top of that. But you win roughly all that lossage back because your heat pump can pump ~3 units of outdoor heat energy into your house for every ~1 unit of electrical energy it consumes.

Add transmission costs and unfortunately heat pumps are more expensive here for now. But CO2 wise of course it still wins because of that renewal and nuclear share I talked about

More importantly, I can also install solar and start getting some energy "for free" (obviously, much more so in the summer than in the winter). And over time of course our renewable share will go up.

Re: I got a heat pump and my energy bill went up

#68

Post by [deleted] »

tommiegannert wrote: post #28

Transparency is great, but let's not forget that the point of switching to electricity is to be able to use renewables. We only have one nice planet to live on, and there are others who want to keep being able to live comfortably on it, I've heard. Oil/gas is a potent drug that is difficult to vane off of. (Arguably solar/battery has the same problem as oil: let's dig and refine stuff from the ground, and not care ab…

[deleted]

Re: I got a heat pump and my energy bill went up

#69

Post by Kim_Bruning »

KptMarchewa wrote: post #53
Kim_Bruning wrote: post #52

Earlier quoted context omitted.

Ah, so ultimately the author did end up paying less. The problem was they were on the wrong plan. And the optimization problem at this point in time is that -ideally- you want to have some amount of excess generation on your solar panels, then time shift that with batteries to a point in time when power is more expensive, and have some amount of excess capacity in batteries so you can also sell that power; versus the…

>And the optimization problem at this point in time is that -ideally- you want to have some amount of excess generation on your solar panels, then time shift that with batteries to a point in time when power is more expensive, and have some amount of excess capacity in batteries so you can also sell that power; versus the (amortized) cost of that extra capacity; and/or what will actually fit on your roof. Yep, that's…

The idea would be to sell excess power in summer to offset the cost of buying power in winter.

For sure this won't work equally well everywhere, and I'm not sure if this would still work once practically everyone has solar; but right now it's plausible.

Re: I got a heat pump and my energy bill went up

#70

Post by harg »

rlpb wrote: post #64
tommiegannert wrote: post #28

Transparency is great, but let's not forget that the point of switching to electricity is to be able to use renewables. We only have one nice planet to live on, and there are others who want to keep being able to live comfortably on it, I've heard. Oil/gas is a potent drug that is difficult to vane off of. (Arguably solar/battery has the same problem as oil: let's dig and refine stuff from the ground, and not care ab…

> let's not forget that the point of switching to electricity is to be able to use renewables Here in the UK, natural gas is used to provide electricity[1], so switching to a heat pump right now isn't likely to help with the environment and (because gas is vastly cheaper per unit energy) nor the utility bill. You might as well spend the capex on the insulation upgrades required for a heat pump anyway, but then stay o…

You get more heat out of using a given quantity of gas to generate electricity which is used to to power a heat pump than you do by burning the gas directly for heat, even when considering generation and transmission losses etc.

Given that even during a time of low output from renewables we still only rely on 53% gas for electricity generation it's still much more beneficial environmentally to use a heat pump.

The monetary cost is another story though, and I agree we do need to work on weaning ourselves off gas.

Post reply on HN