Who has gone all electric in a colder climate?

[La Bibliotecaria Feroz]

We want to replace our gas furnace with an electric heat pump. We live in Denver, so the winters are medium cold. Please don't try to talk us out of the furnace replacement. My husband cannot smell gas, so we are trying to eliminate gas from our home, and we also have like a 10 to 15° temperature difference between the upstairs and downstairs and we do not want half measures. It's not like we can afford to move, we have five people and 1800 square feet, we need the basement to be livable!

Anyway, I had the first visit toward getting an estimate today, and the guy was trying to convince me that I do not want to go all electric because my electric bills will be too high. He says they are really pushing hybrid systems, where the backup heat runs on gas. I think there are some folks around here who have made the switch, so I wanted to hear what people's experiences have been. Is he right that it's a huge mistake to go all electric?

[seattlecyclone]

We live in Seattle. We replaced our old gas furnace with a Daikin heat pump system a little over a year ago. No gas furnace backup, and I'm pretty sure our system didn't come with electric resistance heating backup either. This is of course more of a mild climate than you have. We had an unusually cold week this winter, with temps hovering in the 15-25F range for three days straight. Our electric usage went up dramatically during this time, and also our system was unable to maintain our desired temperature when the outside temp was below 20F. It was still blowing warm air, just not quite enough of it to make up for heat lost to the outdoors.

We have a house with about 2,000 finished square feet and about 500 square foot unfinished basement. It's 100 years old, not well insulated at all. Pulling data from our smart meter...we use about 20 kWh in a typical spring/fall day when the heat pump is idle. On a more typical Seattle winter day with temps in the 40s we use about 50 kWh (so 30 kWh on the heat pump). The coldest day with a low of 15F we used 162 kWh (142 kWh for heat pump). In other words, we spent about $20 to heat our house that day. Such days are extremely rare here though.

All this is to say that in a place like Denver where the average daily low is about 20F lower than Seattle in mid-winter, you're probably going to want something besides just a heat pump. Whether a heat pump with electric resistive backup will be good enough, or if you really will save a bunch of money by having a gas furnace for the cold days is something I can't answer for you.

[nereo]

We have, three times

First was in our condo in Quebec, where we had a heat pump coupled with a couple baseboard heaters. Worked brilliantly, even down to -30°F. IIRC the heat pump functioned down to -14°F before a resistance coil kicked in to make it basically a radiant heater with a fan in it.

Then we removed the 40 year old boiler in our previous home in Maine and have installed four heat pumps (a single exterior and a triple) plus a single 8k heater for extreme weather (might be overkill).  We are also putting in s pellet stove as much for the ambiance as for a back up heating system for power outages (the pellet stove will have a power backup). We will occasionally get nights that go into the single negative digits but going colder than the rating on our heat pumps (-17°F) has not happened in the last 40 years.

[Paper Chaser]

I bought an all electric house in the lower Midwest last summer. Google says my location sees average low temps pretty similar to Denver, but average highs stay about 10 degrees cooler here. Denver sees ~30 degree delta between low/high temps each month while I see ~20 degree deltas. Similar lows, but I don't get as warm each day.
It's been a full remodel down to the studs, so no full time occupancy yet, but my electricity consumption in Dec was about 6 times what it was in July.
It has a heat pump AC with forced air furnace (not a ductless mini-split style). I kept the indoor temp set to 60F during colder months, and kept the AC set to 80F for dehumidification purposes in warm months.
I don't have the water heater on since there's no need for hot water.
I've added new windows and exterior doors since Summer as the old ones were damaged and leaked a lot of air.
Insulation and air sealing was below current standards upon purchase, but is being improved as the rehab moves forward.

With it being an unoccupied rehab, it may not be the best data point, but I think it's safe to say that your cold season usage will be pretty high. A lot of it depends on how well insulated your home is, and how your specific furnace or heat pump system is specced and implemented in your home.

[rockeTree]

If the heat switch allows you to eliminate gas service to the house altogether I would consider that you are avoiding the gas fixed charge which here at least is a couple hundred bucks a year before you use a single therm, helps cover higher winter costs. And insulate insulate insulate. The tech definitely exists to run electric only in your climate but you have to seal the place. Your utility probably has a program to do it fairly cheaply and you are likely eligible for substantial credits under the IRA (check out the rewiring America calculator for number specific to your state/income/etc.)

[Retire-Canada]

We want to replace our gas furnace with an electric heat pump. We live in Denver, so the winters are medium cold.

We have an electric heat pump. Coastal BC so coldest part of winter is normally -10C/+14F and summers get up to +30C/86F. The heat pump doesn't have any issues with that temp range and is fairly efficient to operate in terms of cost. Our system does have an emergency heating mode if thing got so cold it didn't work normally. That's never kicked in even in an extended cold snap. It's nice to have heat/AC in the same system. Of all the heating types I've had including forced air gas furnace and baseboard electric the heat pump is the nicest.

Our heat pump is 14 years old so I'm mentally getting ready to replace it in the next 6-11 years and pay the $$$ costs.

[FLBiker]

I've lived in Nova Scotia for 4 winters, and our house is all electric (and was built in the mid-90s).  We have baseboard resistance heat as our primary heat (per insurance) but we use it very little -- I set the basement at 13C and the rest of the house at 15C.  What we actually use for our primary heat is a pellet stove on the first floor, and a heatpump on the second floor.  It works great, and our electric bill is very reasonable, despite our rate being quite high here.  We'll typically have a few cold spells in the -10C to -15C range (where the heatpump continues to be fine), and I think the coldest overnight temp we had was -25C.  The heatpump doesn't work great then, but the pellet stove still does.

Coming from Tampa, I had no real heat experience, but I like this setup.  Some neighbors have wood stoves, which appeal to me because they can run without power, but they require a lot more work than a pellet stove.  And some have oil furnaces, but those folks all seem to be phasing out their furnaces.  Heatpumps (ductless, typically) are VERY popular here.  Personally, I really like the pellet stove, but it's probably a bit more expensive than a heatpump.  I just like the vibe, and it's better in extremely cold weather (but that's so rare for us it probably doesn't really make sense).

@nereo - I don't want to derail the thread, but I'd be very curious to learn what you're planning to do for a power backup for your pellet stove if you don't mind PMing me.  I've currently got ours on a UPS, but that just buys me another hour or two.  I've toyed with something more substantial, but I haven't done it yet.  Our power is very reliable, though.

[Sibley]

The heat pump can heat your house, the question is can the house retain the heat long enough for the heat pump to be effective. Do you have insulation? Is it enough? Are your windows and doors decently air sealed?

I put a heat pump + gas furnace combo in at my house. I did the combo because while I'm sure the heat pump can heat the house, I'm equally sure the house will lose heat quickly enough that I won't be happy. It's more efficient for a gas furnace when its really cold. It switches over at 50F.

Edit: as Beach Bound stated, I'm referring to cost efficiency at low temps. In my area, gas is cheaper than electric so the cost efficiency switches over to gas at a pretty high temperature.

[Beach_Bound]

You can estimate your future costs with a heat pump using your current utility bill. I plan to switch to a heat pump (23 year old AC and 80% efficient gas furnace... hopefully the HEEHRA rebates become available soon) and have run some of the calculations.

Before jumping into the numbers, a warning that when people talk about "efficiency" of heat pumps, sometimes they mean energy efficiency (heat provided per energy input), and sometimes they mean cost efficiency (heat provided per dollar input). You can see that in this thread: when Nereo says "the heat pump functioned down to -14°F before a resistance coil kicked in" that's energy efficiency. When Sibley says "it's more efficient for a gas furnace when its really cold" that's cost efficiency.

Heat pumps are always more energy efficient than gas furnaces. A gas furnace burns gas and keeps most but not all of the generated heat in your house. Newer models may be 92-96% efficient. My old one is 80% efficient. Heat pumps move heat rather than generate it. At worst, they're 100% efficient (basically just resistance heat). At warmer temperatures, they're much more efficient. For example, in the link below, the MXZ-8C48NAHZ model is 100% efficient at 5F, 270% efficient at 17F, and 375% efficient at 47F (efficiency = COP x 100).
https://www.greenbuildingadvisor.com/question/need-to-know-mitsubishi-heat-pump-cops-at-temps-below-17-degrees-f

However, gas is usually much cheaper than electricity per unit of energy. It's common at low temperatures for gas to be more cost efficient than heat pumps, while heat pumps are still more energy efficient.

Energy star uses a metric called HSPF (heating seasonal performance factor) to measure heat pump efficiency over a heating season. It's the ratio of BTUs of heat provided per watt hours of electricity used over the heating season. New heat pumps must have a HSPF of at least 7.2 to receive the energy star designation.
https://www.energystar.gov/products/heating_cooling/heat_pumps_air_source/key_product_criteria

In my case, last heating season I used 430 CCF of natural gas to heat my house, at roughly $1.40 per CCF, or $602 total. I got this from my utility bills by summing the natural gas consumed during the winter months. My furnace is 80% efficient, so 430 x 80% = 344 CCF worth of heat stayed in my house. If I instead had a heat pump with a HSPF of 7.2, then I would have used 4778 kWh to heat my house over that same time period.

(344 CCF) x (100,000 BTU/CCF) / (7.2 HSPF) / (1000 kWh/Wh) = 4778 kWh
1 CCF = 100 cubic feet = 100,000 BTU

My electricity costs last heating season were around $0.12 per kWh, so that 4778 kWh of heating would cost $573. That's a bit cheaper than the cost of natural gas. However, this year natural gas is more like $1.2 per CCF ($516 to heat for a season) and electricity is $0.13 per kWh ($621 to heat for a season), so the heat pump looks less attractive. I also pay $15 per month in connection fees for natural gas. Removing those fees makes the heat pump costs much more favorable.

For that reason, I plan to get electric resistance supplemental heat rather gas back up. The few days a year that I need supplemental heat will be much more expensive with electric resistance heat than with gas, but I won't be paying the other 360 days a year for a gas connection that I barely use.

You can substitute your own usage and costs to estimate how your bills would change with a heat pump. I looked at the entire heating season, but you could look at a single month's usage and get a reasonable estimate for your future monthly bills.

Please let me know if any of my numbers seem off! If I made a mistake, I'd rather find out before I get a heat pump.

[K-ice]

We removed all gas in a Quebec condo and just used electric baseboards. It works very well. Hydro Quebec electricity is very reasonable. Probably the least expensive per kWh in all of N. America. Any increase in electric was offset by the crazy high service fees you get with a gas bill even if you have zero usage.   

Especially if the system was coupled with solar panels it would be a great investment. 

[oldladystache]

Gas leak detectors are readily available and not expensive. I'd look at that before going all electric.

[nereo]

Before jumping into the numbers, a warning that when people talk about "efficiency" of heat pumps, sometimes they mean energy efficiency (heat provided per energy input), and sometimes they mean cost efficiency (heat provided per dollar input). You can see that in this thread: when Nereo says "the heat pump functioned down to -14°F before a resistance coil kicked in" that's energy efficiency. When Sibley says "it's more efficient for a gas furnace when it’s really cold" that's cost efficiency.
K

I’m really glad you brought that up and explained it so eloquently. There is so much confusion around the concept of “effeciency” and a lot of people assume (incorrectly) that a heat pump is a poor choice in cold climates because the energy efficiency (more specifically the HSPF) does drop precipitously as the exterior temperature drops, but you are going from ~300% Efficency around 50°F to ~125% Efficency in single digits to ultimately 100% Efficency around ~-17°F. Which must be compared to older furnaces (~80%) or modern “HE” furnaces (92-96%) with condenser units.

[sonofsven]

We want to replace our gas furnace with an electric heat pump. We live in Denver, so the winters are medium cold. Please don't try to talk us out of the furnace replacement. My husband cannot smell gas, so we are trying to eliminate gas from our home, and we also have like a 10 to 15° temperature difference between the upstairs and downstairs and we do not want half measures. It's not like we can afford to move, we have five people and 1800 square feet, we need the basement to be livable!

Anyway, I had the first visit toward getting an estimate today, and the guy was trying to convince me that I do not want to go all electric because my electric bills will be too high. He says they are really pushing hybrid systems, where the backup heat runs on gas. I think there are some folks around here who have made the switch, so I wanted to hear what people's experiences have been. Is he right that it's a huge mistake to go all electric?

I would get more quotes from installers and ask them that question.  You might think that someone in the business of installing furnaces would be cognizant of these things, but it's not necessarily true.

[Sibley]

We want to replace our gas furnace with an electric heat pump. We live in Denver, so the winters are medium cold. Please don't try to talk us out of the furnace replacement. My husband cannot smell gas, so we are trying to eliminate gas from our home, and we also have like a 10 to 15° temperature difference between the upstairs and downstairs and we do not want half measures. It's not like we can afford to move, we have five people and 1800 square feet, we need the basement to be livable!

Anyway, I had the first visit toward getting an estimate today, and the guy was trying to convince me that I do not want to go all electric because my electric bills will be too high. He says they are really pushing hybrid systems, where the backup heat runs on gas. I think there are some folks around here who have made the switch, so I wanted to hear what people's experiences have been. Is he right that it's a huge mistake to go all electric?

I would get more quotes from installers and ask them that question.  You might think that someone in the business of installing furnaces would be cognizant of these things, but it's not necessarily true.

At least in my area, there are a LOT of hvac companies who are resistant to new tech, and heat pumps are considered new tech. So not just get quotes but also gets quotes from companies that actually work with heat pumps. Otherwise, you're more likely to get the knee-jerk "that won't work" answer.

[nereo]

We want to replace our gas furnace with an electric heat pump. We live in Denver, so the winters are medium cold. Please don't try to talk us out of the furnace replacement. My husband cannot smell gas, so we are trying to eliminate gas from our home, and we also have like a 10 to 15° temperature difference between the upstairs and downstairs and we do not want half measures. It's not like we can afford to move, we have five people and 1800 square feet, we need the basement to be livable!

Anyway, I had the first visit toward getting an estimate today, and the guy was trying to convince me that I do not want to go all electric because my electric bills will be too high. He says they are really pushing hybrid systems, where the backup heat runs on gas. I think there are some folks around here who have made the switch, so I wanted to hear what people's experiences have been. Is he right that it's a huge mistake to go all electric?

I would get more quotes from installers and ask them that question.  You might think that someone in the business of installing furnaces would be cognizant of these things, but it's not necessarily true.

At least in my area, there are a LOT of hvac companies who are resistant to new tech, and heat pumps are considered new tech. So not just get quotes but also gets quotes from companies that actually work with heat pumps. Otherwise, you're more likely to get the knee-jerk "that won't work" answer.

+1. My experience with trades is that they are very much a product of the region they’ve worked in, and are extremely resistant to change. I can’t tell you how many conversations I’ve had with HVAC companies who would say versions of “but heat pumps don’t work in the kind of cold we get here” - even though they’ve been in extensive use in Canada for decades a couple hundred miles to the north and in a much colder climate.

Definitely find out what companies in you area have been installing heat pumps for a decade or longer, and ask them to do a manual J calculation and show you all the inputs used.  Any installer worth their salt can do this but it’s shocking how many can’t or just don’t bother.

[uniwelder]

Energy star uses a metric called HSPF (heating seasonal performance factor) to measure heat pump efficiency over a heating season. It's the ratio of BTUs of heat provided per watt hours of electricity used over the heating season. New heat pumps must have a HSPF of at least 7.2 to receive the energy star designation.
https://www.energystar.gov/products/heating_cooling/heat_pumps_air_source/key_product_criteria
...
Please let me know if any of my numbers seem off! If I made a mistake, I'd rather find out before I get a heat pump.

I want to add the HSPF is based off the climate of particular place, somewhere in New Jersey I think.  Since the energy efficiency of a heat pump varies based on the outdoor temp, the actual HSPF you will experience will differ depending on how your climate compares to the baseline (New Jersey?)  There is some kind of formula that utilizes the heat pump output and efficiency over several temperatures.

Definitely find out what companies in you area have been installing heat pumps for a decade or longer, and ask them to do a manual J calculation and show you all the inputs used.  Any installer worth their salt can do this but it’s shocking how many can’t or just don’t bother.

Also make sure the heat pump is being sized for the coldest design temperature.  https://www.energystar.gov/ia/partners/bldrs_lenders_raters/downloads/County%20Level%20Design%20Temperature%20Reference%20Guide%20-%202015-06-24.pdf
For Denver, that seems to be 3 degrees F.  A heat pump rated for 24,000 btu/hr will not put out that amount at 3 degrees, so make sure they take that into consideration.  It could be 70% or it could be 95% or that amount.

edited to add--- I have a heat pump with no backup element.  My climate isn't as cold as your's though, since my design temperature is 16 degrees.  It certainly gets colder than that, perhaps 0-5 degrees, but only a day or two per year and usually only for several hours, so its not considered worthy of designing a system around.

[pdxvandal]

I live in a relatively mild climate (PNW) and my 18-year-old gas furnace circuit board croaked just before Xmas. There are many shyster HVAC companies nowadays and unfortunately my first "quote" was from one of them. In addition to trying to sell me a gas furnace that has been federally outlawed since 2023 due to its low SEER rating, they wanted to clean my ducts, replace my working gas water heater, install some fancy wifi thermostat all for the low, low price of $25k. It was like having a GD time-share presentation in my own home for 90 minutes. I had been researching heat pumps and the sales shyster basically tried to dissuade me from one (maybe they had a lot of gas-only furnaces in stock?). And for the record, their initial tech who came out misdiagnosed the problem. The second quote from a smaller company who didn't upsell me at all and actually diagnosed the issue gave me both gas and electric heat pump options for a much, much lower price. It pays to shop.

[nereo]

I live in a relatively mild climate (PNW) and my 18-year-old gas furnace circuit board croaked just before Xmas. There are many shyster HVAC companies nowadays and unfortunately my first "quote" was from one of them. In addition to trying to sell me a gas furnace that has been federally outlawed since 2023 due to its low SEER rating, they wanted to clean my ducts, replace my working gas water heater, install some fancy wifi thermostat all for the low, low price of $25k. It was like having a GD time-share presentation in my own home for 90 minutes. I had been researching heat pumps and the sales shyster basically tried to dissuade me from one (maybe they had a lot of gas-only furnaces in stock?). And for the record, their initial tech who came out misdiagnosed the problem. The second quote from a smaller company who didn't upsell me at all and actually diagnosed the issue gave me both gas and electric heat pump options for a much, much lower price. It pays to shop.

"Clean my ducts" sounds like an industry metaphor for screwing the customer with un-needed services.

Definitely get a couple of quotes for things you actually want (not what they try to sell you). 

[pdxvandal]

nereo: "Clean my ducts" sounds like an industry metaphor for screwing the customer with un-needed services.

Ha! So true. For the record, we've had some unseasonably cold weather since my heat pump install and my electric bills were MUCH higher (plus 18% electric utility increase Jan. 1). We'll see how it goes when the weather warms a bit. Also, I still have gas lines to water heater, range, fireplace and outdoors. WH or range might go electric eventually, but not completely getting rid of gas, just minimizing its use.

[La Bibliotecaria Feroz]

Gas leak detectors are readily available and not expensive. I'd look at that before going all electric.

I have some but I don't love trusting the lives of my husband and baby to something I bought on Amazon for forty bucks!

This is a great discussion, everyone! It will take me some time to sit down and process it all.

I did have another guy come out to do an estimate yesterday. The guy that came on Monday works with a fairly big company that does a lot of volume and a lot of heat pumps, but they do only hybrids Where your backup. Heat is gas. The guy that came yesterday, they are a smaller newer business but electrifying is their specialty and he was a lot more upbeat. Obviously about going electric! But I haven't seen his proposal yet.

[sonofsven]

We want to replace our gas furnace with an electric heat pump. We live in Denver, so the winters are medium cold. Please don't try to talk us out of the furnace replacement. My husband cannot smell gas, so we are trying to eliminate gas from our home, and we also have like a 10 to 15° temperature difference between the upstairs and downstairs and we do not want half measures. It's not like we can afford to move, we have five people and 1800 square feet, we need the basement to be livable!

Anyway, I had the first visit toward getting an estimate today, and the guy was trying to convince me that I do not want to go all electric because my electric bills will be too high. He says they are really pushing hybrid systems, where the backup heat runs on gas. I think there are some folks around here who have made the switch, so I wanted to hear what people's experiences have been. Is he right that it's a huge mistake to go all electric?

I would get more quotes from installers and ask them that question.  You might think that someone in the business of installing furnaces would be cognizant of these things, but it's not necessarily true.

At least in my area, there are a LOT of hvac companies who are resistant to new tech, and heat pumps are considered new tech. So not just get quotes but also gets quotes from companies that actually work with heat pumps. Otherwise, you're more likely to get the knee-jerk "that won't work" answer.

+1. My experience with trades is that they are very much a product of the region they’ve worked in, and are extremely resistant to change. I can’t tell you how many conversations I’ve had with HVAC companies who would say versions of “but heat pumps don’t work in the kind of cold we get here” - even though they’ve been in extensive use in Canada for decades a couple hundred miles to the north and in a much colder climate.

Definitely find out what companies in you area have been installing heat pumps for a decade or longer, and ask them to do a manual J calculation and show you all the inputs used.  Any installer worth their salt can do this but it’s shocking how many can’t or just don’t bother.

Yes to this, and also many companies only work with limited brands and manufacturers, so they will often push those products without telling you there is a better one.

[Shuchong]

Have you considered a geothermal/ground source heat pump?  You may be able to get subsidies to cut down on the costs of install, which are usually ridiculously high.  The advantage is that they work well in cold weather, and are generally more efficient than normal heat pumps. 

[beege]

We have a small (750 sq foot) house in a cold climate. We converted from a diesel heater (Toyo stove) to an air-sourced heat pump (the smallest one Fijitsu makes) two winters ago. It has been pretty awesome. This year we had significant precipitation and we were a little concerned about the ice buildup around the system but it has kept working. I think I will probably move it a bit next summer to put it in a better spot where the roof doesn't shed as much snow around it. It actually doesn't get super cold here but we had a couple solid weeks of 0 degree (F) days and it kept chugging no problem. Our installer didn't even put in the cold weather version and recommended against it since those are less reliable.

The important thing our installer mentioned was to shield it from precipitation and wind so it's in a semi-enclosed space but still with plenty of ventilation. It runs all the time and water vapor condenses on it and ice can build up around it; keeping water and snow off it helps a lot.

Electric is pretty expensive here but cost-wise I think we are doing about the same as the diesel - maybe a little ahead; regardless of the cost we have peace of mind (our toyo stove leaked all over the floor once) and the toyo also occasionally smelled a bit when the wind came up and back-drafted. It feels good to get a combustion source out of our house.

We also converted to an electric (cook) stove but that's not much of a savings, if any but more of an air quality thing. Get a good ventilator hood to go with it.

We still have a wood stove as a backup source of heat. Not a bad idea since it's cold here a bit.

[BlueMR2]

Have not gone electric myself, but know a few people that are all electric.  For comparable sized houses here in the Great Lakes region, they seem to average around twice as much per sq foot on electric vs. gas+non-heating electric people.  I'd think it'd probably be fine if you don't regularly get below freezing, but when it's getting to double digit negatives even gas is getting pretty pricy.

[Catbert]

If you haven't already, ask this question on a neighborhood app or Facebook page.  Not only will their climate be identical but they'll also be buying gas and electric from the same company.  If you're in a subdivision you may have an identical home or one with similar construction.

[nereo]

If you haven't already, ask this question on a neighborhood app or Facebook page.  Not only will their climate be identical but they'll also be buying gas and electric from the same company.  If you're in a subdivision you may have an identical home or one with similar construction.

The problem I frequently encounter with asking neighbors is that their answers are often incomplete or wrong. Besides the tendency to misrepresent their true cost (either over or under reporting, depending on whether they want to seem more “green” or engage in “my bills are so high!”), all to often mix up or not report sources.

For example, all-electric homes include non-heating energy loads like the refrigerator(s), home theatre and charging EVs. It also includes hot water which largely flows down the drain, and cooking which might primarily get vented to the exterior.

At the same time people who “heat with [oil/gas/propane]” will leave out that they have an electric space heater in their office or a wood-burning/pellet stove, or that they do a ton of baking when it’s cold, and their oven is electric.

All too often I learn that a household really has no clear idea what their heating costs are because they have 2-4 heating sources which all bill at different frequency (eg monthly for electric, 6-9 weeks for heating oil depending on weather and 1x annually for wood, some of which may be “left over” from previous years. And too often I get the sensation that people really, really want to stay in the dark regarding how much they actually spend.

A much, much more accurate way is simply to use the cost of electricity, gas, propane etc in your area (including hook-up fees or delivery) and calculate from there. There are some good calculators out there will will account for the variable energy efficiency of heat pumps and link it to the weather in your climate region.

[former player]

Electric is safer than gas, it's more environmentally friendly (especially if your supplier uses renewables) and with a heat pump it's more efficient (as explained by Beach_Bound and Nereo).

Like beege I've gone all electric with a woodstove for backup.  No regrets.

[CowboyAndIndian]

I will go to a heat pump when my furnace/water heater dies.

Pros of going with a heat pump

• Safer due to lower number of combustion sources in the house (would still have a gas stove, clothes dryer)
• Air quality improvement in the house
• Longer life than a gas furnace
• I have solar, so my expenses will be much lower.
• Replace 2 units (ac/furnace) with just one (heat pump).
• The heat pump hot water heater would get rid of the  dehumidifier in basement
• The possiblity of dropping off the grid for energy(at least for a short time). I lived thru Sandy outages, the NE electrical grid failure, so this is an important feature

Cons

• Gas is very cheap in the US. Not so in the rest of the world. So, is it cost efficient?
• My solar is undersized for a heat pump. Will have to add 4.5kw panels. Not needed on day one and I can take my time to implement this
• Additional cost due to electrical work (220v connections) which will be needed for the install.

As of now I have 8.5 kw panels and 2 powerwalls (26kwh storage in each).

@Beach_Bound, the explanation of cost and energy efficiency was nicely done. Really learned from  your comment.

[Beach_Bound]

Energy star uses a metric called HSPF (heating seasonal performance factor) to measure heat pump efficiency over a heating season. It's the ratio of BTUs of heat provided per watt hours of electricity used over the heating season. New heat pumps must have a HSPF of at least 7.2 to receive the energy star designation.
https://www.energystar.gov/products/heating_cooling/heat_pumps_air_source/key_product_criteria
...
Please let me know if any of my numbers seem off! If I made a mistake, I'd rather find out before I get a heat pump.

I want to add the HSPF is based off the climate of particular place, somewhere in New Jersey I think.  Since the energy efficiency of a heat pump varies based on the outdoor temp, the actual HSPF you will experience will differ depending on how your climate compares to the baseline (New Jersey?)  There is some kind of formula that utilizes the heat pump output and efficiency over several temperatures.

Good point! Yes, HSPF is based off a climate profile from zone IV (which includes NJ, but I couldn't find if the profile was actually based on a NJ location). I'm also in zone IV, so I forgot that it may be different in other zones. Denver is zone V (colder), so heat pumps will likely be less energy efficient there.
https://basc.pnnl.gov/images/iecc-climate-zone-map

Based on the linked weather comparison below, Denver has a longer heating season than the Philly area (where I am), but Denver's average low temperatures are usually above 20F, so the decrease in efficiency is probably not too significant.
https://weatherspark.com/compare/s/3/3709~22721/Comparison-of-the-Average-Winter-Weather-in-Denver-and-Philadelphia#Figures-Temperature

[former player]

I don't know if this is right but I remember reading that in a cold climate a ground source heat pump is more efficient/useful than an air source heat pump.  (I was considering this because if climate change switches off the gulf stream the UK is likely to become significantly colder over time.)

[nereo]

I don't know if this is right but I remember reading that in a cold climate a ground source heat pump is more efficient/useful than an air source heat pump.  (I was considering this because if climate change switches off the gulf stream the UK is likely to become significantly colder over time.)

It is, but the upfront cost of drilling can be substantial (several thousands to tens of thousands depending on how deep they need to drill and if there is rock involved.

The conceptual part is like this: air source heat pumps work at whatever the external air temperature is and push heat across that gradients. When you want it to be 20°C inside (68°F) and it’s -10°C outside (+14°F) the heat pump has to push across that difference (“delta” of 30°F). T that’s is why they get less efficient in colder temps in a nutshell.

Ground source pumps a loop of glycol underground where the temperature is always a constant 10°C (50°F), but in summer and winter. The delta then is always 10° and the heat pump will run at maximum efficency always, even when it gets brutally cold (or exceptionally hot) outside.

Installing involves a drill rig in your garden and a few hundred feet of pex. We really wanted to do this but our home sits on ledge so the quotes were >$50k for us. Too bad… was our first choice. Instead we are just putting money towards a deep energy retrofit

[La Bibliotecaria Feroz]

We live on a 5700 square foot lot (and a slice of that is the "dirt slope" which is unusable and behind a fence) so I don't think ground source would be practical even if we had the money!

After calling 3 companies, I have only 1 proposal for the heat pump. It is $19K, and that’s only if we commit by the end of the month. That means no time to get a second proposal but I’ve had a shocking amount of trouble finding companies that do this work and don’t insist on gas for the backup heat.

That’s for one of those Mitsubishi Hyper Heat pumps that everyone is talking about and also includes an optional $2K to have the ducts sealed with Aeroseal, which is supposed to make it cheaper to run but we can skip if we want. Going to really sit down with it later and the guy and I have a call scheduled for Monday to discuss in more detail.

(Of the three, one sent an estimator but then flat-out refused to write us a quote for all electric,* and the other one- who did our heat pump water heater last year- said that they are revamping their offerings right now so not doing sales.

*This guy was still useful, though- he suggested that running our blower more often might even out the temperature difference and it does seem to have upped the basement temperature by about 4F.

[nereo]

Ugh - I’m so sorry, though im not terribly surprised. It’s tough to get trades to do anything “new” (to them)

[kenner]

Good luck with the heat pump options, didn't notice this before but I'm a bit north of you and have always been all-electric for the simple reason that gas doesn't run to my place.  ~900 sq feet above ground and the same below, and the heat pump has always managed just fine even on the stretch of negative F degree days we seem to have started having every winter.  There is a definite spike in usage on those days, something like 2-3x kWh per day over a day where it's just hanging out right around freezing, and an associated increase in costs which this year meant $10-$12/day on those days rather than $3-$5/day average for the rest Jan, so for me nothing that would make me thing that adding gas at the $$$$ a few neighbors have spent would be anywhere near worth it.

[NorCal]

I've responded to a few of these questions before, but figured I'd chime in for anyone reading that hasn't read my comments.

I'm in Denver, and replaced my gas furnace with a Mitsubishi heat-pump just shy of two years ago.  Here's my observations in no particular order.

Context: 3,400 sqft house in Denver.  Moderatly well insulated and air sealed with R40 in the attic.  I plan to do some additional air sealing over the next few years.

1. The system runs fine in Denver with no backup.  Don't let anyone tell you otherwise (although different brands may be a different story).  Insulation and air-sealing matter as well.  We had a day that was -16F last winter, and the system kept up just fine.

2. Operating costs are slightly higher than my old system, but it's really a rounding error.  It is absolutely more expensive in the winter, but it has a higher SEER than my old AC unit, so cooling costs are lower.  Gas prices have been all over the place in the last few years, ranging from $0.7/therm to $2/therm, so it also depends on what you're assuming for gas prices.  They're currently around $1/therm and headed to $1.1/therm if XCEL's rate increase goes through.  I haven't been able to measure it precisely, but I estimate the heat-pump is break-even with gas in the $1.2 to $1.3/therm range.  I'll consider it break-even once I remove my fixed $12/month fixed gas meter fee.

3. The variable speed system has reduced temperature differentials we had in the house before.  The upstairs was always hard to cool in the summer.  It hasn't eliminated this difference entirely, but it has cut it maybe in half. 

4. Make sure you look at all of the incentives.  Hopefully your installer will point you in the right direction.  In Denver, there's the federal tax credit, sizeable XCEL rebates ($1,500 to $2,000 IIRC), and the city of Denver has rebates that vary on what you buy ($5,500 for a cold-climate heat pump IIRC).  The incentives are big enough to justify switching to a heat-pump in Denver when your current AC or furnace dies, but not large enough to financially justify getting rid of an existing working system. 

5. Installers and HVAC techs mostly partner with companies that don't do cold-weather heat-pumps.  Search for either home electrification companies, or contractors familiar with the high quality cold weather systems.  I'm aware of Mitsubishi and Bosch.  I believe there are a few others. 

6. Look into heat-pump water heaters if you're considering starting electrification of your home, but aren't ready to commit to an hvac overhaul.  The financial returns of the water heater are much better, and it's a lower cost project.  You'll save roughly 50% on water heating costs switching from gas. 

[La Bibliotecaria Feroz]

@NorCal - I would love to hear more about your up-front cost (what I've been quoted seems high to me- close to $20K AFTER the upfront rebates??) and what your SEER is.

Do you literally not have backup heat? So far one place quoted us on a backup gas furnace and the other place's quote includes electric resistance backup.

We actually have a heat pump water heater! Unfortunately it dropped the temp in the basement about 4F, widening the gap. But we did all the electrical upgrades when we did the water heater, so we presumably need a new circuit in the attic for the heat pump but we don't need a panel upgrade.

[NorCal]

@NorCal - I would love to hear more about your up-front cost (what I've been quoted seems high to me- close to $20K AFTER the upfront rebates??) and what your SEER is.

Do you literally not have backup heat? So far one place quoted us on a backup gas furnace and the other place's quote includes electric resistance backup.

We actually have a heat pump water heater! Unfortunately it dropped the temp in the basement about 4F, widening the gap. But we did all the electrical upgrades when we did the water heater, so we presumably need a new circuit in the attic for the heat pump but we don't need a panel upgrade.

$20k after the rebates sounds high, but the rebates have changed since I did my system.  Mine was a little over $20k before rebates and $12k after rebates.  It was a 4 ton ducted Mitsubishi system.

I don't have the numbers off the top of my head, but I believe my prior AC was SEER 14 and the new Mitsubishi setup is SEER 18. 

I don't have any backup heat, and it's been fine.  Even on that -16F day last year.  But you want a contractor that will run an actual Manual J calculation on whether you need it or not.  Insulation and air sealing matter here.  My relatively modern Central Park home came pretty well insulated.  I have a friend that just had a Mitsubishi installed by Elephant Energy.  Elephant said, "well, we can install backup heat strips for $3k, or you can go buy a space heater or two for the super cold days".  They bought the space heaters and saved a lot of money. 

I would trust any contractor that is doing an actual Manual J calculation on your home, and not trust any contractor that isn't. 

I personally used Helio Home as a contractor.  I had some issues with their subcontractors, so I hesitate to recommend them.  But they told me they don't work with those subcontractors anymore and I have friends that have used them and been happy.  Elephant Energy (which I previously recommended) also has a good reputation among my friends that have installed heat pumps. 

[jeninco]

@NorCal - I would love to hear more about your up-front cost (what I've been quoted seems high to me- close to $20K AFTER the upfront rebates??) and what your SEER is.

Do you literally not have backup heat? So far one place quoted us on a backup gas furnace and the other place's quote includes electric resistance backup.

We actually have a heat pump water heater! Unfortunately it dropped the temp in the basement about 4F, widening the gap. But we did all the electrical upgrades when we did the water heater, so we presumably need a new circuit in the attic for the heat pump but we don't need a panel upgrade.

$20k after the rebates sounds high, but the rebates have changed since I did my system.  Mine was a little over $20k before rebates and $12k after rebates.  It was a 4 ton ducted Mitsubishi system.

I don't have the numbers off the top of my head, but I believe my prior AC was SEER 14 and the new Mitsubishi setup is SEER 18. 

I don't have any backup heat, and it's been fine.  Even on that -16F day last year.  But you want a contractor that will run an actual Manual J calculation on whether you need it or not.  Insulation and air sealing matter here.  My relatively modern Central Park home came pretty well insulated.  I have a friend that just had a Mitsubishi installed by Elephant Energy.  Elephant said, "well, we can install backup heat strips for $3k, or you can go buy a space heater or two for the super cold days".  They bought the space heaters and saved a lot of money. 

I would trust any contractor that is doing an actual Manual J calculation on your home, and not trust any contractor that isn't. 

I personally used Helio Home as a contractor.  I had some issues with their subcontractors, so I hesitate to recommend them.  But they told me they don't work with those subcontractors anymore and I have friends that have used them and been happy.  Elephant Energy (which I previously recommended) also has a good reputation among my friends that have installed heat pumps.

Thanks for all this! We're up northwest of you (in, er, "Hippistan") and I actually had a conversation with an installer who suggested it made more sense to put in a heat pump for house-heating ahead of a heat-pump water heater, because we use a lot more gas to heat the house than to heat the water.

I'll call both Elephant and Helio on Monday: we're waiting for our permits for a medium-sized renovation, and these are both on our radar (our existing water heater is 20 years old...)

[GilesMM]

Ugh - I’m so sorry, though im not terribly surprised. It’s tough to get trades to do anything “new” (to them)

I don’t get this. Our “new to us” place has heat pumps from 2008 installed by the same local HVAC company around today.  There was gas available then so not sure what the thinking was but glad they did it because the house has solar now to defray costs of electricity.

[nereo]

Ugh - I’m so sorry, though im not terribly surprised. It’s tough to get trades to do anything “new” (to them)

I don’t get this. Our “new to us” place has heat pumps from 2008 installed by the same local HVAC company around today.  There was gas available then so not sure what the thinking was but glad they did it because the house has solar now to defray costs of electricity.

What is it that you don’t “get”? Could you rephrase what you mean?

[GilesMM]

Ugh - I’m so sorry, though im not terribly surprised. It’s tough to get trades to do anything “new” (to them)

I don’t get this. Our “new to us” place has heat pumps from 2008 installed by the same local HVAC company around today.  There was gas available then so not sure what the thinking was but glad they did it because the house has solar now to defray costs of electricity.

What is it that you don’t “get”? Could you rephrase what you mean?

I don't get that HVAC contractors are playing dumb that heat pumps are not a thing in 2024 when they have been a thing for ages.

[mistymoney]

Interesting to hear the perspective here. I do plan to convert to all electric and add solar before RE. Midwestern weather.

[uniwelder]

Ugh - I’m so sorry, though im not terribly surprised. It’s tough to get trades to do anything “new” (to them)

I don’t get this. Our “new to us” place has heat pumps from 2008 installed by the same local HVAC company around today.  There was gas available then so not sure what the thinking was but glad they did it because the house has solar now to defray costs of electricity.

What is it that you don’t “get”? Could you rephrase what you mean?

I don't get that HVAC contractors are playing dumb that heat pumps are not a thing in 2024 when they have been a thing for ages.

Historically, heat pumps were used in mild climates because (even the hvac guys I've talked to currently) say they don't work in below freezing  temperatures.  As the technology has improved, the hvac people stuck with what they know.  Also, a lot of people don't want to pay for a good system that actually works at low temps, so they install the cheapest they can and then complain that heat pumps aren't any good.

In your case, it sounds like you've lived in very mild climates, so certainly, hvac people are very comfortable with heat pumps because they've been viable options for 35+ years.  In Denver, the design temperature is 0 degrees F, so a system that'll work in that temperature has only been available mainstream in the US for maybe 10 years or so?

[Sibley]

Ugh - I’m so sorry, though im not terribly surprised. It’s tough to get trades to do anything “new” (to them)

I don’t get this. Our “new to us” place has heat pumps from 2008 installed by the same local HVAC company around today.  There was gas available then so not sure what the thinking was but glad they did it because the house has solar now to defray costs of electricity.

What is it that you don’t “get”? Could you rephrase what you mean?

I don't get that HVAC contractors are playing dumb that heat pumps are not a thing in 2024 when they have been a thing for ages.

Historically, heat pumps were used in mild climates because (even the hvac guys I've talked to currently) say they don't work in below freezing  temperatures.  As the technology has improved, the hvac people stuck with what they know.  Also, a lot of people don't want to pay for a good system that actually works at low temps, so they install the cheapest they can and then complain that heat pumps aren't any good.

In your case, it sounds like you've lived in very mild climates, so certainly, hvac people are very comfortable with heat pumps because they've been viable options for 35+ years.  In Denver, the design temperature is 0 degrees F, so a system that'll work in that temperature has only been available mainstream in the US for maybe 10 years or so?

I had a heat pump when I lived in CA, and oh boy did that thing struggle when it got cold. It was fine 40s and up, but when it dropped to the 30s it just didn't work well, and I suspect below freezing may not have worked at all. It would get ice build up inside the unit when it was really cold. Putting that unit into a house somewhere where it drops to zero would be a terrible idea. That's what a lot of people think about though.

[NorCal]

Ugh - I’m so sorry, though im not terribly surprised. It’s tough to get trades to do anything “new” (to them)

I don’t get this. Our “new to us” place has heat pumps from 2008 installed by the same local HVAC company around today.  There was gas available then so not sure what the thinking was but glad they did it because the house has solar now to defray costs of electricity.

What is it that you don’t “get”? Could you rephrase what you mean?

I don't get that HVAC contractors are playing dumb that heat pumps are not a thing in 2024 when they have been a thing for ages.

A lot of it has to do with the brands that most HVAC contractors associate with.

Most contractors seem to prefer working with 1-2 manufacturers they know well.  Maybe they support Carrier or Lennox, and that's what they work with.

There are absolutely heat-pump brands that work in cold temperatures.  Except these are generally higher-end brands (Mitsubishi, Bosch, etc) that don't have a big presence in the mass-market where most customers/techs are in their comfort zone. 

I watched part of the install on my Mitsubishi unit, and there are absolutely differences in complexity and installation compared with a traditional AC.  The refrigerant is charged differently, the thermostats are proprietary with proprietary programing and pairing.  I'm sure it's learnable, but it's not quite as simple as swapping out one brand for another. 

[La Bibliotecaria Feroz]

We signed a contract on a Mitubishi Hyper Heat! But we are still waffling on the the backup heat. The sales guy was like, well, you might wake up it would be like 63 degrees, which... is warmer than our basement normally.

If we do not have a backup system, will our pipes freeze if we go out of town and the temperature becomes super duper low? Not sure it even gets cold enough in Denver to totally freeze out a Hyper Heat- they are supposed to run down to like -22F?

I don't want to be pennywise and pound foolish but I also don't want to pay three grand for a whole appliance that we don't REALLY need. We have pretty high cold tolerance and already own several space heaters. I'm seeing that a lot of people have wood or pellet stoves as backup (NOT an option we are considering- our house is just too small for us to have anywhere to put one, aside from them not being the most toddler-friendly situation), and presumably they would be in the same position if they travelled in cold weather (no one home to light the stove).

Anyway! Thoughts on skipping backup heat? Would it be stupid to skip it or pretty much okay?

[uniwelder]

Anyway! Thoughts on skipping backup heat? Would it be stupid to skip it or pretty much okay?

For $3,000, I'd skip the backup and just plug in your space heaters.  If the case of power outage, perhaps get a small kerosene heater?

[jeninco]

Anyway! Thoughts on skipping backup heat? Would it be stupid to skip it or pretty much okay?

For $3,000, I'd skip the backup and just plug in your space heaters.  If the case of power outage, perhaps get a small kerosene heater?

If the situation you are worried about is a power outage while you're out of town, there's not much you can do besides insulate your house just as much as you can, and hope the power comes back on in time. Which, in the case of our reasonably-insulated late 50's house, is over 3 days: our power went out during the windstorm that caused the Marshall fires, and almost 3 days later when it came back on the house was still in the high 40's: pretty darned cold, but nowhere near pipe-freezing temps.

[WayDownSouth]

Gas leak detectors are readily available and not expensive. I'd look at that before going all electric.

I have some but I don't love trusting the lives of my husband and baby to something I bought on Amazon for forty bucks!

This is a great discussion, everyone! It will take me some time to sit down and process it all.

I did have another guy come out to do an estimate yesterday. The guy that came on Monday works with a fairly big company that does a lot of volume and a lot of heat pumps, but they do only hybrids Where your backup. Heat is gas. The guy that came yesterday, they are a smaller newer business but electrifying is their specialty and he was a lot more upbeat. Obviously about going electric! But I haven't seen his proposal yet.

You will definitely want to have gas backup. You can buy the best gas detectors on the market if you want. You say you don't trust the lives of your husband and child to something you bought on Amazon, but how about trusting the lives of everyone to the power grid and electric companies?

Nobody in their right mind, even with a generator and space heaters, should go full electric when living in a climate like yours. Think carefully about that, please. I'm from the midwest and have spent a night or two with no electric in an all-electric home during an ice-storm that took out power. We had no generator. We had alcohol, and we had lots of blankets. By the end of the first day when the house is only 15 degrees warmer than outside, layers of clothes and blankets just don't cut it.

Imagine in a long-term outage - weeks or more.... You cannot sleep and breath in air that measures near-zero temps. You need gas backup, AND, you need a powerful generator.

[NorCal]

I’m in the camp of backup heat is not needed in Denver. My Mitsubishi (likely nearly identical to what you’re getting) kept my house warm on that -16 day. That was tied for the record Denver cold of all time IIRC.

Assuming this is one of the larger Mitsubishi units, it probably puts out about 36k btu’s below freezing. A standard 1,500W space heater puts out about 5k btu.  You can supplement heat very cheaply with a space heater or two. Your oven will also put out significant heat in an emergency.

If a power outage is your concern, think carefully about how your backup setup would actually solve the problem. If it’s a standard gas ducted furnace, it still needs electricity to run the air handler. Gas backup doesn’t solve the power outage problem unless you have a truly electricity free  system. I doubt that’s what you were quoted.

Your neighborhood may be different, but I have pretty good confidence in electric reliability in Denver proper. I’ve had maybe 2 hours of combined power outages in the last 5 years. I would feel different if I lived in a rural area that had storms taking down power lines on a semi-recurring basis.