Green / Eco-Friendly

How many KWh do you use in a day?

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Emporium wrote: Does that include heating and hot water ? I'm Jealous Astonished Face
Lucky I live in QC and we have cheap electricity. for the last 62 days, I have consumed 10822 kWh (average of 174.5kWh/day) - average temperature of -6C. For a whopping total of $1080.48 for 62 days.

1300sq ft x2 floors (total 2600ft), semi-detached. But I have a 20kW electric Furnace and keep home temp on average around 21 to 22C, 60G electric hot water tank, household of 4 (who love their HOT showers), 2 large fridges, and we cook a lot so oven sees it's share of use.

Summer months, I average 55 to 60kWh per day.
Your consumption level is insane.
Hot water and heat are your largest consumers, but at -6 hot water may actually be using more energy than heat. Unless your house is an energy efficiency disaster.
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Quentin5 wrote: Your consumption level is insane.
Hot water and heat are your largest consumers, but at -6 hot water may actually be using more energy than heat. Unless your house is an energy efficiency disaster.
I even checked with quite a few of the neighbours, and many are at that level and typically more. Been in the house for 20+ years, and I've replaced all the windows. When I reno'd many rooms, I'd increase the insulation. All lights have been swapped out with LED, and it barely makes a dent.

With a 20kW (4x 5kW elements) furnace, even if it runs at half capacity (10kW) for 33% duty cycle, I'm looking at 3.3kW x 24hrs which about 80kW just in heating per day. The hot water tank is surely a huge culprit. I can see the consumption spike between 7pm and 10pm (when everyone takes their showers), but it settles down after around 11:30pm when it recovers. It does use 4.5kW after all, so it if runs at full for 4 hrs to recover, that is another 18kWh. But when I see people doing 176kWh in a month, and I use that in a day it is scary :) I would have figured Hydro would have knocked on my door thinking I had a grow-op :)

Unfortunately, Natural gas is not an option in my area, and Oil heating will soon be banned in my city (within the next 10 years), so electric is my only option.

Truth is, I don't want to walk around my house with sweaters, blankets, and mittens either. It is at a more than comfortable temperature.

Are there a few air leaks around the house, I am sure there are still a few (it's built in 1964 after all). But nothing major left, most have been addressed. It is a fight of diminishing returns.
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Emporium wrote: I even checked with quite a few of the neighbours, and many are at that level and typically more. Been in the house for 20+ years, and I've replaced all the windows. When I reno'd many rooms, I'd increase the insulation. All lights have been swapped out with LED, and it barely makes a dent.

With a 20kW (4x 5kW elements) furnace, even if it runs at half capacity (10kW) for 33% duty cycle, I'm looking at 3.3kW x 24hrs which about 80kW just in heating per day. The hot water tank is surely a huge culprit. I can see the consumption spike between 7pm and 10pm (when everyone takes their showers), but it settles down after around 11:30pm when it recovers. It does use 4.5kW after all, so it if runs at full for 4 hrs to recover, that is another 18kWh. But when I see people doing 176kWh in a month, and I use that in a day it is scary :) I would have figured Hydro would have knocked on my door thinking I had a grow-op :)

Unfortunately, Natural gas is not an option in my area, and Oil heating will soon be banned in my city (within the next 10 years), so electric is my only option.

Truth is, I don't want to walk around my house with sweaters, blankets, and mittens either. It is at a more than comfortable temperature.

Are there a few air leaks around the house, I am sure there are still a few (it's built in 1964 after all). But nothing major left, most have been addressed. It is a fight of diminishing returns.
I would love to see an energy audit of your house.
I would guess hot water and heating are your big users.
In efficient homes hot water can use more than heating but it seems like your spending a lot of juice on both.

Unfortunately new windows don't save much energy. They save some energy but the payback period is often 75-150 years.
In fact in Rand McNally they wear hats on their feet and hamburgers eat people
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Jun 10, 2003
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Emporium wrote: I even checked with quite a few of the neighbours, and many are at that level and typically more. Been in the house for 20+ years, and I've replaced all the windows. When I reno'd many rooms, I'd increase the insulation. All lights have been swapped out with LED, and it barely makes a dent.

With a 20kW (4x 5kW elements) furnace, even if it runs at half capacity (10kW) for 33% duty cycle, I'm looking at 3.3kW x 24hrs which about 80kW just in heating per day. The hot water tank is surely a huge culprit. I can see the consumption spike between 7pm and 10pm (when everyone takes their showers), but it settles down after around 11:30pm when it recovers. It does use 4.5kW after all, so it if runs at full for 4 hrs to recover, that is another 18kWh. But when I see people doing 176kWh in a month, and I use that in a day it is scary :) I would have figured Hydro would have knocked on my door thinking I had a grow-op :)

Unfortunately, Natural gas is not an option in my area, and Oil heating will soon be banned in my city (within the next 10 years), so electric is my only option.

Truth is, I don't want to walk around my house with sweaters, blankets, and mittens either. It is at a more than comfortable temperature.

Are there a few air leaks around the house, I am sure there are still a few (it's built in 1964 after all). But nothing major left, most have been addressed. It is a fight of diminishing returns.
Get a blower door test done to see just how bad your place is, even if you have done a lot of work already I bet being that it was built in the 60's that its still very leaky. Another option is to install a heat pump, there are good ones like Fujitsu extra low temp ones that will be more efficient than your furnace even down at -26c. The vast majority of the time the heat pump will be working at a ~3x efficiency gain over your furnace which would save you a ton but heat pumps work slowly so making sure your place is fairly air tight and well insulated is important.

My two Fujitsu's preformed so well this winter that I will be removing my natural gas line this spring, the heat pumps are cheaper. I keep my upstairs at 21c all the time and the basement at 18c, last month I used 1500kWh for my 2000 sq ft house and ~800kWhs of that was space heating. If you do get heat pumps really make sure you know what you are buying, how they are rated and how to compare them. A common rating for heating is "HSPF" but you have to be careful when comparing HSPF numbers between heat pumps. The tests are run for different climate zones and you can only compare numbers if you know they were tested in the zone this explains in more detail. I think I spent a good year researching mine before I finally settled with the Fujitsu ones.
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instanoodles wrote: My two Fujitsu's preformed so well this winter that I will be removing my natural gas line this spring,
I take it you have ductless HPs? If not (or even if), what are the recommended ducted heat pumps in the Halifax area? The link you posted seems to favour the Carrier Greenspeed?
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Between 8-10 kWh in the current non-AC, WFH, environment. It goes up to the 15-20 kWh range on laundry day.

According to Alectra on my January bill "You ranked 167 out of 2693 similar accounts in your area for this billing period."
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Jun 10, 2003
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thriftshopper wrote: I take it you have ductless HPs? If not (or even if), what are the recommended ducted heat pumps in the Halifax area? The link you posted seems to favour the Carrier Greenspeed?
Yeah I went with ductless because my place had no ductwork, it has baseboard hot water. I never looked into the big ducted heat pumps but Daikin came up a lot as a quality manufacturer.
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instanoodles wrote: Yeah I went with ductless because my place had no ductwork, it has baseboard hot water. I never looked into the big ducted heat pumps but Daikin came up a lot as a quality manufacturer.
It may be (and I certainly thought so) but that link you provided seems to think the Daikin has performance issues under certain conditions.
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Avg 18-20 kWh/day during non-AC season. Too much TV I guess.

Kids doing home schooling, now averaging closer to 22 kWh/day
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thriftshopper wrote: It may be (and I certainly thought so) but that link you provided seems to think the Daikin has performance issues under certain conditions.
It certainly doesn't seem to perform as well as the carrier and thats why it is really important to understand how these things are rated when comparing different units.
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instanoodles wrote: Get a blower door test done to see just how bad your place is, even if you have done a lot of work already I bet being that it was built in the 60's that its still very leaky. Another option is to install a heat pump, there are good ones like Fujitsu extra low temp ones that will be more efficient than your furnace even down at -26c. The vast majority of the time the heat pump will be working at a ~3x efficiency gain over your furnace which would save you a ton but heat pumps work slowly so making sure your place is fairly air tight and well insulated is important.

My two Fujitsu's preformed so well this winter that I will be removing my natural gas line this spring, the heat pumps are cheaper. I keep my upstairs at 21c all the time and the basement at 18c, last month I used 1500kWh for my 2000 sq ft house and ~800kWhs of that was space heating. If you do get heat pumps really make sure you know what you are buying, how they are rated and how to compare them. A common rating for heating is "HSPF" but you have to be careful when comparing HSPF numbers between heat pumps. The tests are run for different climate zones and you can only compare numbers if you know they were tested in the zone this explains in more detail. I think I spent a good year researching mine before I finally settled with the Fujitsu ones.
That it is still leaky it is ( I don't doubt it), but it is a lot better than when I bough it 20yrs ago (where every windows was leaking around the casings), and doors (front and back) were useless for air infiltration. They've been replaced. But some areas are not as easy to get too, like behind walls/cabinets. I have ripped out the worst ones, and sealed, insulated and put up new vapor barrier, but I can't do them all. Some I have to live with for now, but they are no longer as obvious as the ones I had.

In terms of heat pump, I install a new mini-split last year (since my old Mitsubishi finally failed after 15yrs and made no sense to put money in repairing it). I installed it upstairs in the main living room area, and it spills a little into the other rooms. Unfortunately, I don't have any ducting, and layout of the house is such that one central unit just can't heat all the space (especially in colder temps).
I got a Senville SENA/24HF which is 20 SEER - ENERGY STAR Certified, and HSPF(4) rating of 11.5 (which is pretty respectable. It has been running continuously since late fall, and even at -20C outside it still produces a good amount of heat. I considered the Fujitsu, but at the end of the day I got 3 quotes and the Fujitsu came it at roughly 3.5x the cost of the Senville unit (at least from local suppliers). A friend has 3 Senville units now for nearly 7 years now and he loves them and another friend has them in 6 rental units and has had no issues, so I went with the recommendation.

My main source of heating is my 20kW electric boiler with water circulation baseboards. I love the water circulation system, but in fall and spring it is a huge energy waster which is why I wait as late as possible to turn it on. I use the heat pump as long as possible exclusively and the occasional spare heater for the remote rooms. In days where it is not too cold, the system will come on, and has to warm up all the water in the closed loop so the room temperatures can rise a degree or 2. Then it stops. BUT then temperature does not drop too quickly so 3 or 4 hours later, when it does finally drop, it will come on again and has too heat up all the water all over again, since it is already cooled off mostly. I know most of the pipes run in the ceilings/walls and are surely NOT insulated, so I'm warming up a lot of the space between the ceilings and upper floor. I have been insulating them as I reno different rooms in the house, but I am not going to take down all the ceilings and bulkheads in one shot to insulate all the pipes :(

Other big factors:
- 2x 20yr old fridges don't help much either I guess.
- With the pandemic, both kids have their desktop PC (and laptops - but those are negligible) running at least 10 to 12hrs per day (if not more).
- Double garage door (even though it is a new insulated door - about 5 yrs old - with triple seals), every time we open it, it is a huge energy loss.
- At least 2 loads of laundry a day (since wife works in a hospital - and I sometimes go into the office - so everything goes straight to the laundry when we get back), and in winter time the dryer is used a lot more since we don't hang dry on clothes line, so that is a huge energy guzzler.
- 60Gal. electric hot water tank, with 4 people in the house, with daily showers in the evenings, has the tank working constantly for at least 4 to 5 hours to recover.

Next year, I may add a second mini-split in the basement area to help a little more with the heating situation.

Lucky at least for one thing in QC.. Cheap hydro power..
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Jun 10, 2003
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Emporium wrote: That it is still leaky it is ( I don't doubt it), but it is a lot better than when I bough it 20yrs ago (where every windows was leaking around the casings), and doors (front and back) were useless for air infiltration. They've been replaced. But some areas are not as easy to get too, like behind walls/cabinets. I have ripped out the worst ones, and sealed, insulated and put up new vapor barrier, but I can't do them all. Some I have to live with for now, but they are no longer as obvious as the ones I had.

In terms of heat pump, I install a new mini-split last year (since my old Mitsubishi finally failed after 15yrs and made no sense to put money in repairing it). I installed it upstairs in the main living room area, and it spills a little into the other rooms. Unfortunately, I don't have any ducting, and layout of the house is such that one central unit just can't heat all the space (especially in colder temps).
I got a Senville SENA/24HF which is 20 SEER - ENERGY STAR Certified, and HSPF(4) rating of 11.5 (which is pretty respectable. It has been running continuously since late fall, and even at -20C outside it still produces a good amount of heat. I considered the Fujitsu, but at the end of the day I got 3 quotes and the Fujitsu came it at roughly 3.5x the cost of the Senville unit (at least from local suppliers). A friend has 3 Senville units now for nearly 7 years now and he loves them and another friend has them in 6 rental units and has had no issues, so I went with the recommendation.

My main source of heating is my 20kW electric boiler with water circulation baseboards. I love the water circulation system, but in fall and spring it is a huge energy waster which is why I wait as late as possible to turn it on. I use the heat pump as long as possible exclusively and the occasional spare heater for the remote rooms. In days where it is not too cold, the system will come on, and has to warm up all the water in the closed loop so the room temperatures can rise a degree or 2. Then it stops. BUT then temperature does not drop too quickly so 3 or 4 hours later, when it does finally drop, it will come on again and has too heat up all the water all over again, since it is already cooled off mostly. I know most of the pipes run in the ceilings/walls and are surely NOT insulated, so I'm warming up a lot of the space between the ceilings and upper floor. I have been insulating them as I reno different rooms in the house, but I am not going to take down all the ceilings and bulkheads in one shot to insulate all the pipes :(

Other big factors:
- 2x 20yr old fridges don't help much either I guess.
- With the pandemic, both kids have their desktop PC (and laptops - but those are negligible) running at least 10 to 12hrs per day (if not more).
- Double garage door (even though it is a new insulated door - about 5 yrs old - with triple seals), every time we open it, it is a huge energy loss.
- At least 2 loads of laundry a day (since wife works in a hospital - and I sometimes go into the office - so everything goes straight to the laundry when we get back), and in winter time the dryer is used a lot more since we don't hang dry on clothes line, so that is a huge energy guzzler.
- 60Gal. electric hot water tank, with 4 people in the house, with daily showers in the evenings, has the tank working constantly for at least 4 to 5 hours to recover.

Next year, I may add a second mini-split in the basement area to help a little more with the heating situation.

Lucky at least for one thing in QC.. Cheap hydro power..
Wow yeah you just use a ton of energy and hard to make any major gains. You should get rid of the fridgesat least, new ones use like 1-1.5kWhs a day and I wouldnt be surprised if those used 4-5.

Only other things I could think of was if you could get your hands on a thermal camera you could check and see if you have an cold spots in your walls/ceiling.

They also make ventless heat pump dryers you could look into, they use about a 1/3 of the energy a regular dryer does. Everytime you run a full load through your dryer you are also tossing out about the entire volume of air in your house outside. You end taking the air you have already heated, heat it more in the dryer, toss it outside which will draw in fresh outside air which you have to heat again. I have a whirlpool heat pump dryer and it works quite well but its slow, at 1.5 hour+ cycle time it may take too long for your needs.
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instanoodles wrote: They also make ventless heat pump dryers you could look into, they use about a 1/3 of the energy a regular dryer does. Everytime you run a full load through your dryer you are also tossing out about the entire volume of air in your house outside. You end taking the air you have already heated, heat it more in the dryer, toss it outside which will draw in fresh outside air which you have to heat again. I have a whirlpool heat pump dryer and it works quite well but its slow, at 1.5 hour+ cycle time it may take too long for your needs.
Could go for a HP water heater too. Question I have about internal heat pumps: Won't they just absorb heat from inside the house which would mean energy usage? Or is that usage just less than sucking cold air from outside?
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thriftshopper wrote: Could go for a HP water heater too. Question I have about internal heat pumps: Won't they just absorb heat from inside the house which would mean energy usage? Or is that usage just less than sucking cold air from outside?
Pretty much, I looked into getting one and it didnt make very much sense. My house is very air tight so any heat it moves I have already paid to condition and I didnt want to add ducts going outside for it. If you have a boiler room then a heat pump water heater would work really good with the excess heat the boiler gives off and during the summer it would help cool the house a bit.
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Emporium wrote:
My main source of heating is my 20kW electric boiler with water circulation baseboards.
I got one last thing you could look into, an air to water heat pump from Arctic Heat Pumps. I looked into them to replace my natural gas boiler originally but I decided I didn't want the water base boards in the end. They are made in Canada and they seemed just as efficient as the Fujitsu's I got and you could probably keep your existing boiler too for those few super cold days.
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instanoodles wrote:
Wow yeah you just use a ton of energy and hard to make any major gains. You should get rid of the fridgesat least, new ones use like 1-1.5kWhs a day and I wouldnt be surprised if those used 4-5.

Only other things I could think of was if you could get your hands on a thermal camera you could check and see if you have an cold spots in your walls/ceiling.

They also make ventless heat pump dryers you could look into, they use about a 1/3 of the energy a regular dryer does. Everytime you run a full load through your dryer you are also tossing out about the entire volume of air in your house outside. You end taking the air you have already heated, heat it more in the dryer, toss it outside which will draw in fresh outside air which you have to heat again. I have a whirlpool heat pump dryer and it works quite well but its slow, at 1.5 hour+ cycle time it may take too long for your needs.
1.5hrs for a dryer load is not too long, considering a load in the LG He washer is about that also, so while second load is being washed, the first load can dry.
I honestly never knew heatpump dryers existed. Just saw the This Old house video. It's a shame that I just bought a brand new conventional dryer less than a year ago (my 23yr old maytag was beyond economical repair. The dryer is used mostly in the winter. In the summer I have a huge clothes line in the back yard, and the only thing the dryer is used for in the summer is to dry towels to pick up the lint.

Only downside I see of the heat pump dryer is the cost.. Quick glance, after taxes, it is just over $2K.. Considering a typical el-cheapo dryer will run about $450, that is still $1550 difference. In QC with standard D rate of 9.4cents/kWh (for anything more than 40kWh per month), that is the equivalent of nearly 16500kWh.. That is a hell of a lot of drying :) With a typical dryer being about 5kW, and typical load about 45 minutes, that's about 3.75kWh per load. which means I will break even only after nearly 4400 loads :) And I have not even considered the energy that the Heatpump unit will use anyhow. I'll write that off as the wasted additional energy, due to the venting of a conventional dryer. It's a GREAT concept, but the prices are still too high to justify, at least here in Quebec where the energy costs are so low. In many other areas, where price of electricity is 4 or 5 times our rate, I can see it making sense, with a payback in about 3 or 4 years. In QC it would take at least 10yrs to break even (assuming a whopping average of 10 loads /week - which is not even close considering summer season, I don't use it much), so it would be closer to 15yrs (typical lifespan of the appliance). And that assumes no repairs needed. On conventional dryer repairs are pretty simple for most DIY (replace a belt, replace an element, a timer, etc..), mostly basic stuff and not too pricey (unless the motor goes, at that point makes no sense to repair. Heat Pump you will need a specialist to look at it.

I do appreciate however that you brought this option up. I honestly did not know that they had started making these dryers. I'm sure eventually these will replace conventional dryer, but not just yet.

1 Fridge will be replaced in the next year (with the Kitchen remodel). I will put my Kiilawatt meter on them to see what they use daily, out of curiosity.
Funny that you mentioned a thermal camera. I was honestly just looking at this one yesterday. OK, it is NOT a professional unit, but for this purpose, and most DIY needs, it should be sufficient.


thriftshopper wrote: Could go for a HP water heater too. Question I have about internal heat pumps: Won't they just absorb heat from inside the house which would mean energy usage? Or is that usage just less than sucking cold air from outside?
That has always been my concern. My hot water tank is in my utility room, with electrical panel, network patch panel, washer/dryer, sink, hot water tank, and electric boiler for the water circulation heating system. It is about a 100 sq ft room, and not overly warm, just average. Wouldn't a HP hot water tank draw the heat out of the surrounding air, and in effect cool the room down ?

The unit I have right now, is a 60Gallon Super Cascade. It has 2x 4500 elements, foam Insulated double glass-lined inner tank, and bottom entry making it a little more efficient. They now have their new EcoPeak model which use a 3 element system, and hydro QC is offering $100 rebates on each tank, since they decrease the peak demands. But I am concerned with our usage habits, it may not be able to keep up. And it doesn't really save any energy really. it is just better no the grid, due to 3 smaller elements (max draw of 3800W) instead of 2 larger ones (max draw of 4500W).

Really appreciate all the input guys.
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instanoodles wrote:
Pretty much, I looked into getting one and it didnt make very much sense. My house is very air tight so any heat it moves I have already paid to condition and I didnt want to add ducts going outside for it. If you have a boiler room then a heat pump water heater would work really good with the excess heat the boiler gives off and during the summer it would help cool the house a bit.
Depends on the boiler. Gas or oil burning furnaces I agree they have a lot of excess heat. My electric boiler, is 20kW, but all the hot water is pumped straight into the black steel pipes, and not a huge footprint in the utility/boiler room. So there is not much excess heat.
instanoodles wrote: I got one last thing you could look into, an air to water heat pump from Arctic Heat Pumps. I looked into them to replace my natural gas boiler originally but I decided I didn't want the water base boards in the end. They are made in Canada and they seemed just as efficient as the Fujitsu's I got and you could probably keep your existing boiler too for those few super cold days.
These are awesome. At least the idea. Price for the units is a little higher than traditional, but not too bad overall. This for me would have a pretty decent ROI if they work as detailed in thier documents. Only issue is distribution. I just looked up for a local supplier/installer, and looks like there is only 1 in QC. They are not too far, but I looked up the exact address, and it is a "Public Storage" facility :) And if I go to their website, I see some units (no Arctic Heat Pumps brand - seem to have their own rebrands), but looks like just a distributor of various items, but no mention of installation. And when I opened one of their installation documents (for their brand of Air to Water HP), on the second to last page, it says it comes with only a 1 Year warranty.. $7K for a sizeable heat pump and another $1K for a storage tank, is fine, but only 1 year warranty... Hmm... Not very confidence inspiring.
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I guess heat pump water heaters and dryers must be designed for climates that are much milder than we have, then, and are meant to draw unwanted heat. Doesn't stop my province for offering incentives to choose them though.
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thriftshopper wrote: I guess heat pump water heaters and dryers must be designed for climates that are much milder than we have, then, and are meant to draw unwanted heat. Doesn't stop my province for offering incentives to choose them though.
I have both a heat pump dryer and heat pump water heater. When the dryer is running, the "waste" heat is absorbed by the water heater.

In terms of the math on the water heater energy wise:

My Rheem unit has a COP of 3.8 (1kWh electricity = 3.8 kWh of heat moved)
My home is heated by a ground source heat pump at a COP of 4.0.

My effective water heating COP during the heating season is still about 2 because I need 1 kWh to bring 4 kWh of heat into the house, then another kWh to put those 4 kWh into the tank, so for every 4 kWh of heat into the tank I need to use 2 kWh of electricity.

At my rental property where I have a similar set up but the home heating is provided by cold climate air source heat pump
DHW COP 3.8
Heating COP 3.8 - 2.0 (drops below 2 at temperatures below -18°C I believe, without looking it up again)

So in that case I need to use 2 kWh of electricity to bring 4 kWh of heat into the house in the cold of winter, then 1 kWh of electricity to put those 4 kWh into the hot water, so the COP is only 1.33. When temperatures are 8°C or above it's 1 kWh ot bring the heat in, 1 kWh to put the heat in the tank, so COP of about 2 again

From mid-May until mid-September when the home is not being heated the COP of the water heater is the full 3.8. You could argue that during the cooling season (mid-June to mid-September) the COP is even greater as the cool air expelled from the unit, and the dehumidification from the unit are "free". I'd be paying for those functions separately anyways, but in this case the waste heat energy is being used for a function.

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