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I got a heat pump and my energy bill went up

heatpumped.org

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

#121

Post by tharkun__ »

StillBored wrote: post #120
triceratops wrote: post #119

Earlier quoted context omitted.

> In areas with moderate outdoor temperatures. Anywhere that the heatpump is going through defrost cycles, that statement is likely false because the COP is likely 1 or less when that starts happening. Modern heat pumps have a COP close to 2 at 5F/-15C while still delivering 50k+ BTUs. Here's one example: https://ashp.neep.org/#!/product/68628/7/25000/95/7500/0///0

While heating, That isn't even a particularly efficient unit (EER 9), and not all all unusual for r410 (which is basically banned for new sales in the USA since jan 1st) But it has a 150W pan heater, but I don't think that is its primary defrost mode, at least its not going to be at 50k btu at those temperatures unless its also really dry. The pan heater is probably to just assure that the coil melt water doesn't bui…

Not your parent. We had a Fujitsu AOU15RLS3 installed ~10 years ago. 25.3 SEER apparently, EER 13.9. Also r410A. We mainly got it for AC in summer but we'll take the heating of course. Pretty cold winters here.

    Minimum Outdoor Temperature for Heating: -5°F
Yeah that's about as cold as it's right now actually. During the day!

We'll definitely use the propane fireplace in winter, especially when the power goes out, which has happened more frequently in recent years, as "proper winter" has given way to more freeze / thaw type stuff with ice storms.

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

#122

Post by dilyevsky »

BeefWellington wrote: post #32
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…

PG&E is basically California, where it can hit north of $0.50/kWh pretty regularly. I think it's worth noting in this article too that the author mentions they can now heat and cool parts of their house they weren't previously, so I'm gonna guess their actual usage went up and this is basically surprise for no reason.

Cost of 1 therm from pg&e is $2.66 so variable speed heat pump can still be cheaper

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

#123

Post by sjducb »

thebruce87m wrote: post #98
rlpb wrote: post #64

Earlier quoted context omitted.

> 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…

> 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 You can view the live production here: https://electricityproduction.uk 51% renewables as I write this, and it’s only going to increase over time. I bet the people were arguing about the coal generation until we switched that off. > because gas is vastly cheaper per unit ene…

Great comment, from a carbon perspective it’s even better than 51% .

16% is nuclear, and 19% is imported from France which is about 60% nuclear.

Right now only 10-12% of our electricity is coming from burning gas.

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

#124

Post by 8fingerlouie »

whatevaa wrote: post #93
8fingerlouie wrote: post #31

Personally i save about 75% with my heatpump over my old gas furnace. We used around 1500m3 - 1800m3 worth of natural gas per year, and for the past couple of years we've used between 4000kWh and 5000kWh on the heat pump per year. Granted, natural gas is expensive in Denmark, and while electricity is also normally expensive, if you have electrical heating you're excempt from paying taxes on electricity usage above 40…

What if exemption wasn't in place?

My average price during 2024, with taxes was DKK 0.88/kWh ($0.$12). This number is biased as it includes EV charging typically done at night where electricity prices are low, and the EV takes up about 40% of our electricity consumption. It is however the average price reported by my smart meter for 2024.

The average price for electricity with taxes was DKK 2.77 / kWh [1] ($0.39)

I spent 4600 kWh on the heat pump during 2024, so DKK 4048 ($562) without taxes and DKK 10.764 ($1497) with taxes.

I haven't checked my COP for 2024, but it's usually around 4, meaning I've gotten 18400 kWh worth of heat from those 4600 kWh electricity.

Natural gas has around 10 kWh worth of heat per m3, and assuming an optimistic efficiency of 90% for the gas burner, that is equivalent to 2044 m3 natural gas.

The average price of natural gas in the first 6 months of 2024 in Denmark was DKK 11.09 [1], so DKK 22.667,96 ($3.152,63) would be the price to produce the same heat with natural gas.

So even if paying the full price for electricity, I would still only be spending less than 50% for heating with the heat pump compared to natural gas.

[1]: https://www.dst.dk/en/Statistik/emner/miljoe-og-energi/energ...

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

#125

Post by iosguyryan »

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…

Not to mention the footprint of making something new, disposing the old, and transport.

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

#126

Post by metalman »

Something ignored in the article is that the old gas furnace was of an early and eceptionaly inefficient type, proven by its rotten flue pipe, newer gas furnaces are of the condensing type, and exract so much energy from the exhaust, that it condenses water, and the flue pipes are made of plastic, as the exhaust is barely warm.Older furnaces have hot caustic flue gasses, that will rot and corode the pipes. Total efficiency is what counts from an environmental standpoint, and grid electricity can often come with CO² outputs that are high, per delivered heating energy at the load compared to delivered fuels. Heat pumps realy start to look good, when there is grid tied solar PV, and energy bills can drop to 5% or less of anything else.This works as far north as 45°latitude, at least. But the truth is that even @45°n, a house that is built to the best insulation standards, has no heating system whatsoever, as domestic activities and heat air exhangers alone, will produce excess heat, and party gatherings of organic heat machines, will require opening windows to stay comfortable, in the depths of winter.

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

#127

Post by cjrp »

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…

> Here in the UK, natural gas is used to provide electricity

In the past year, natural gas provided 27.4% of the generated electricity. Wind provided 31.1%. Scroll down on https://grid.iamkate.com and choose "Past year" to see the full breakdown.

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

#128

Post by beepboopboop »

Amorbellum wrote: post #115

I'm in Kitchener Ontario Canada, I'm a licensed gas and refrigeration tech I've pulled my gas meter off my house and I'm exclusively heat pump now. I'm saving money, absolutely. Canada has cold ambient temps and cheap natural gas, and I'm still saving money, so I don't know how you aren't I'm paying 10 cent pretty kwh electricity, gas here is 15 cents per cubic meter

How does your heat pump do on cold days like today? Do you still use an AC in the summer?

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

#129

Post by vfclists »

Should it require that much numeracy and time researching price options to benefit from a heat pump?

Can't it be much simpler?

Not all people have the brains AND assuming that they do, the time to go through these hoops to make their heat pump investment pay off.

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

#130

Post by ac29 »

Amorbellum wrote: post #115

I'm in Kitchener Ontario Canada, I'm a licensed gas and refrigeration tech I've pulled my gas meter off my house and I'm exclusively heat pump now. I'm saving money, absolutely. Canada has cold ambient temps and cheap natural gas, and I'm still saving money, so I don't know how you aren't I'm paying 10 cent pretty kwh electricity, gas here is 15 cents per cubic meter

>and I'm still saving money, so I don't know how you aren't

> I'm paying 10 cent pretty kwh electricity

Electric rates are ~4x that where the author lives.

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