Solar power systems for the home

[Bigtime]

Originally Posted by blender

Are you sure the heat pump is sized correctly?
If it is oversized it will cycle and not run efficiently which can waste a lot of energy.

Also, you want to be sure that you are keeping your thermostat set at one temperature. If your wife (for example) adjust the T-stat based in how she is feeling hour-to-hour it will kill the efficiency.

Oversized heat pumps are the major cause of inefficiency.

The best gas furnace will be 96% efficient under factory testing (probably 90% real world), so you are wasting 10% right out of the gate. Keep that in mind with your calculations.
Electric heat is solid state, so you are getting 100% of the power you put in. A well-sized, properly functioning heat pump can run at 300% efficiency. I doubt you would see that level of efficiency in real world conditions, but they can be significantly more efficient than even regular electric heat.

Yes, all sized correctly by our contractor Solar Homes and AirTech Services. We hold a constant temperature with the thermostat now instead of what we did with the gas furnace setting lower at night.

[Lubicon]

Originally Posted by blender

Are you sure the heat pump is sized correctly?
If it is oversized it will cycle and not run efficiently which can waste a lot of energy.

Also, you want to be sure that you are keeping your thermostat set at one temperature. If your wife (for example) adjust the T-stat based in how she is feeling hour-to-hour it will kill the efficiency.

Oversized heat pumps are the major cause of inefficiency.

The best gas furnace will be 96% efficient under factory testing (probably 90% real world), so you are wasting 10% right out of the gate. Keep that in mind with your calculations.
Electric heat is solid state, so you are getting 100% of the power you put in. A well-sized, properly functioning heat pump can run at 300% efficiency. I doubt you would see that level of efficiency in real world conditions, but they can be significantly more efficient than even regular electric heat.

So programmable thermostats are not necessary and may actually be detrimental?

[Bigtime]

Originally Posted by Lubicon

So programmable thermostats are not necessary and may actually be detrimental?

With our heat pump install we got a new smart thermostat from Daikan. You can program a schedule/away mode and other features. But as blender pointed out (and our contractors) with a heat pump you want to minimize temperature setting swings, as it runs much better with minor variations. If we are going away for a while I will reduce the temperature to an away setting, and let it hum away at that, and then move it back up prior to coming home.

[GGG]

Originally Posted by blender

Are you sure the heat pump is sized correctly?
If it is oversized it will cycle and not run efficiently which can waste a lot of energy.

Also, you want to be sure that you are keeping your thermostat set at one temperature. If your wife (for example) adjust the T-stat based in how she is feeling hour-to-hour it will kill the efficiency.

Oversized heat pumps are the major cause of inefficiency.

The best gas furnace will be 96% efficient under factory testing (probably 90% real world), so you are wasting 10% right out of the gate. Keep that in mind with your calculations.
Electric heat is solid state, so you are getting 100% of the power you put in. A well-sized, properly functioning heat pump can run at 300% efficiency. I doubt you would see that level of efficiency in real world conditions, but they can be significantly more efficient than even regular electric heat.

2200 kWh isn’t terrible, in fact his efficiency is pretty great considering the low ambient temperatures reducing heat pump efficiency. By comparison I used 17GJs of gas last month. That’s 4700 kWh of energy from gas plus my power consumption. I still have my 80% ME furnace but even if you consider the efficiency of CCGT of 50% the gas consumption using the heat pump would still be substantially less than heating conventionally.

[Bigtime]

Also keep in mind that 2200kWh includes things we didn't have prior to this energy reno such as:

-ERV
-Electric hot water tank
-EV charger

I have found the ERV doesn't draw a lot of power (and can be set to cycle on/off for certain amounts of time), but that electric water tank sure does when it fires up. We did install one of those copper drain water heat recovery systems to offset that a bit.

[blender]

Yeah, Bigtime, sounds like you have it dialed.
Sorry if I missed it earlier, but did your contractor do an energy audit on the house and a hot-2000 report (or similar) before they did the work?

[Bigtime]

Originally Posted by blender

Yeah, Bigtime, sounds like you have it dialed.
Sorry if I missed it earlier, but did your contractor do an energy audit on the house and a hot-2000 report (or similar) before they did the work?

2 full energy audits and blower door test done pre and post renovation by another company that was approved for the Greener Homes Grant.

[GGG]

Originally Posted by Bigtime

Also keep in mind that 2200kWh includes things we didn't have prior to this energy reno such as:

-ERV
-Electric hot water tank
-EV charger

I have found the ERV doesn't draw a lot of power (and can be set to cycle on/off for certain amounts of time), but that electric water tank sure does when it fires up. We did install one of those copper drain water heat recovery systems to offset that a bit.

What type of water heater did you go with is that a heat pump model as well or just electric tank?

[DoubleK]

Originally Posted by GGG

What type of water heater did you go with is that a heat pump model as well or just electric tank?

Curious. Is an on demand electric hot water heater a thing? I have had a gas one in the past, but can't think how an electric one would work.

[Bigtime]

Originally Posted by GGG

What type of water heater did you go with is that a heat pump model as well or just electric tank?

Not sure, I'll check what the tank says tonight. It's just like our previous gas heated tank, only that it is fully electric now. It's not an on demand system.

[Bill Bumface]

I got my energy assessment done, and I'm expecting it comes back that my house is leaky AF (113 years old).

I'm going through this for solar, but curious if the home effeciency crew has ideas to address this:

Our basement was at some point partially dug out. The dug out portion has the typical super fat concrete walls underpinning the original footing, so there is a ledge all the way around that space.

The fat concrete walls were crumbling, so a wood foundation wall was built in front of that. It is open at the top where the "ledge" is, but that space is now a few feet deep and only like 12" tall, so not easy to access.

I can insulate/seal the wood foundation wall easily, but what the hell do I do with the "void" at the top? That is where there is tons of leakage due to additions and various utility perforations.

Then we have the crawlspace area... it's a nightmare to crawl around in, but I could access the "ledge" in that space to some feasible extent. It's just awful.

[Fuzz]

That's tough, because you could easily trap moisture against the wood foundation as you attempt to seal stuff up, which I presume would be Bad. I'd say spray foam up top, but you may need a pro to give some options.

[Bill Bumface]

Originally Posted by Fuzz

That's tough, because you could easily trap moisture against the wood foundation as you attempt to seal stuff up, which I presume would be Bad. I'd say spray foam up top, but you may need a pro to give some options.

I asked a pro to do it while they were doing other stuff and they basically said "not enough room, no thanks".

The foundation wall itself is treated, so not terribly concerned about moisture. I'd put vapor barrier on the inside face of the wall to prevent condensation.

[the-rasta-masta]

For those of you who possibly missed out on the first go around of the grant, my company has learned that it sounds like there will be an announcement in late March/early April about a refunded grant program. Not confirmed, but what we are hearing is that it will be the same $5000, with an additional $600 meant to pay you back for the energy audits required, but instead of being paid out after the project will be paid out in advance to make it more accessible to lower income Canadians so they don't have to carry as many costs before installation and payout of the interest free loan proceeds. I'll update as I get more info!

[Bill Bumface]

Originally Posted by Bill Bumface

I asked a pro to do it while they were doing other stuff and they basically said "not enough room, no thanks".

The foundation wall itself is treated, so not terribly concerned about moisture. I'd put vapor barrier on the inside face of the wall to prevent condensation.

Found someone to do it! Beyond Foam came in and basically just quotes it by area. Probably more expensive than a smaller outfit, but meh - 10 year interest free Justin loan.

I'm going to insulate inside the wood foundation myself. It is configured like so:

[outside dirt] -> [old failing concrete foundation] -> [packed gravel] -> [vapour barrier] -> [treated plywood] -> [stud cavity] -> [wall panelling].

I assume the vapour barrier is essentially "exterior" here, but it's complicated, because of the warm air that can still reach that gravel layer.

Should I just throw in some rock wool with no further vapour barrier? Any other ideas?

[Fuzz]

That sounds like a workable setup. The vapour barrier in that location still allows the wood foundation to breath into the house, and I don't see why you couldn't use rock wool in the stud cavities.

[Calgary14]

Anyone notice a slight dip in solar production from the solar eclipse today?

[Bigtime]

Originally Posted by Calgary14

Anyone notice a slight dip in solar production from the solar eclipse today?

Yup:

[cKy]

Originally Posted by the-rasta-masta

For those of you who possibly missed out on the first go around of the grant, my company has learned that it sounds like there will be an announcement in late March/early April about a refunded grant program. Not confirmed, but what we are hearing is that it will be the same $5000, with an additional $600 meant to pay you back for the energy audits required, but instead of being paid out after the project will be paid out in advance to make it more accessible to lower income Canadians so they don't have to carry as many costs before installation and payout of the interest free loan proceeds. I'll update as I get more info!

Has there been any update to this? I'm just about to get my feet wet.

[Twitchy15]

Originally Posted by gasman

Does the heat pump heat exchanger take up much footprint outside? We don't have a lot of good locations near our utility room outside, the only place would be the current location of the air conditioning condenser, would that unit replace the AC?

my heat pump is similar to a slim AC unit, pretty small footprint and yes it replaces your AC. Heat pump is basically a AC that can also run in reverse.