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Incredibly janky port of comments from my old WordPress site:

gordon skinner

2021-11-29 at 7:52 pm

Thank you for the reply to my comment.

My heating is actually 18,000 Kwhr converted from litres of propane.

Propane is tied to oil prices and currently 80 cents Cdn per litre, 24,000 btu

There is a federal tax on carbon which added $350 last year and is increasing every year to 2030

Our electrical is actually 8,000 Kwhr and billed on a time of use basis. includes hot water

Both heat and electricity are typical averages for a house in Canada, Zone 6

We keep the house at 55F at night and the same anytime we are out.

I think the real difference is insulation . My house is a storey and half and the upstairs is all knee walls.

I have 5 different attic areas and a real zoo to re-insulate.

The house is a brick facade so the lower walls are also a problem to fix without tearing out the drywall.

The house is surrounded by so many big trees that the solar guy did not want to install.

In any event, my roof area is not big enough for enough solar and is broken up by dormers and a garage roof going the opposite way.

We have electrical baseboards throughout but are too expensive to use.

Your idea of a heat pump for one room and setting it high is a good one.

We are actually on the same page.

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Profit Greenly (Post author)

2021-12-05 at 8:55 pm

Seeing that you’re in Canada explains your higher energy use to me, you have far colder winters than I do here in State College. Canada is also one of the few places that I don’t whole-heartedly recommend solar, as its production is just so out of sync with you energy use there and a lot of Canada already has good no emission electricity from existing nuclear and hydro. I hear you on the difficulty of insulating your house, but given your high energy bills I still think it may be worth the effort/cost. There are finally some low GWP spray foams on the market, though they can be hard to find and pricey. Here’s DAPs Low GWP Touch N Seal on ebay (https://www.ebay.com/itm/DAP-Touch-N-Seal-600-BF-Low-GWP-1-75-PCF-FR-Closed-Cell-Spray-Foam-Insulate-Kit/313399921697?hash=item48f8174c21:g:-LYAAOSwXJpgFG06). A single 600 board foot kit of that is nearly the price of the small heat pump I recommended though, so maybe just adding one of those is the right first step. If you actually do it, please come back and comment again so I can hear how it went.

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Feb 21, 2022·edited Feb 21, 2022Author

Incredibly janky port of comments from my old WordPress site:

gordon skinner

2021-11-20 at 2:08 pm

great article, well researched and analysed

my house is similar to yours in size and has new windows well-sealed

no obvious caulking spots, all infiltration

however, I use a total 26,000 kwhrs from electricity and equivalent propane usage

I think you stated 11,000 kwhrs for your home plus an ACH of .34?

I have not been able to do the same economics

I believe a blower door test on my house would show 5 or 6 ACH @ 50 pascals

my roof is far too small to make it up with solar

plus would need more than one heat pump

the issue of deep retrofitting existing houses needs to be solved or our climate goals will not be met

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Profit Greenly (Post author)

2021-11-29 at 4:18 pm

Sorry to hear of your home’s high energy use. 11,000 kWh is actually what my solar panels output over a year and it’s near my total energy use for literally everything (cooking, water, EV, etc.). My heatpump only uses a fraction of this (4,000-5,000 kWh each year for both heating and cooling, see my heat pump blog for more details). If you’re using 26,000 kWh just to heat then it’s definitely something worth your time to research.

My home was tested to have a natural ACH of 0.32. That means at normal pressure 32% of my home’s air is changed every hour. Since then I have sealed my chimneys and one other obvious leak area, so this may be down a bit lower. The basic rule of thumb to convert ACHn to ACH @ 50 is to multiply by 20, so I have around 6 ACH @ 50. Given your high use I think a real blower door test would definitely be worth it, because you may have far more air infiltration than you think.

The next thing to look at is your insulation. I’ve got R38 in the attic and likely R3 in the walls. My home is built into a slope though, so 1/2 of the basement is built up against dirt which likely helps. My roof is also unshaded, so I get some heat from the sun.

You should also consider the temperature you keep your home at. I leave my heat set to 68 pretty much all winter long now that we’ve got a couple geckos in the house (they have an extra small heater in their cage to keep them happy). If you have yours set well above this that could explain your high heating use. If you don’t have small animals to worry about you could also consider turning your heat down at night and when you’re out of your house (here’s an explainer on that I wrote for my friend’s blog https://rampantdiscourse.com/leaving-thermostat-wastes-money/).

The other possible explanations would be that you live in a far colder climate than me (I’m in central PA) or that your home has a far greater exterior square footage than mine (my home is pretty much a box, if you’re is like a long snake type design the extra surface area exposed to the outside could explain your high heating needs). Whatever the case, if you’re using 26,000 kWhs just for heat each year you have a huge economic incentive to improve the air sealing and insulation of your home. Even if you pay the low price of $0.10/kWh you’re still looking at $2600/year just for heating, and if you’re paying Massachusetts prices of $0.23/kWh that’s near $6,000/year. You can add a LOT of air sealing and insulation for $6,000/year.

One last thought that may help you. There are now far cheaper heat pumps than the one I bought. This Youtube shows a DIY install of a $1,200 minisplit unit. It only outputs 9,000 BTUs, but you can bump it up to 12,000 BTU for only $1,349. It has an insane efficiency of 15 HSPF (my fancy unit is only 12) and 38 SEER (I’m only 20.5 but in PA cooling is only a small amount of my use). This unit will add over 4 kWh of heat to your home for every kWh you put into it over a heating system. Given your huge energy use it would make sense to add one to your most used room and set it’s thermostat higher than your main heat. That will reduce the heat your main heater uses and make that room and the surrounding areas extra comfortable. As you save money keep installing these in other areas of your home. By the time you have 3 or 4 of them in you may find that your regular heater doesn’t even run anymore. Given your high heating costs it will likely only take a few years of running one of these for it to pay for itself, and after that you will just make money.

https://youtu.be/Kd092alkeaE

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Incredibly janky port of comments from my old WordPress site:

Kate Zod

2021-03-27 at 4:39 am

FYI. I thought you might want to update your article.

“…solar projects in all market segments — residential, commercial, industrial, utility-scale — that begin construction in 2021 and 2022 will still be able to receive a tax credit at 26%. All markets will drop to a 22% tax credit in 2023, and the residential market will drop to 0%, while the commercial and utility markets will sit at a permanent 10% credit beginning in 2024.”

Source:

https://www.solarpowerworldonline.com/2020/12/solar-investment-tax-credit-extended-at-26-for-two-additional-years/

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Profit Greenly (Post author)

2021-03-27 at 11:31 am

Good point, I updated the post!

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