Solar power systems for the home

[gasman]

[QUOTE=gasman;8078343]Storage is currently not a good investment. Economically it doesn't make sense. You offset the cost of the electricity by selling to the grid during the day, and then the energy you use in the evenings, you are only paying the transmission fees on (provided you made enough energy in the daytime)

Then with solar clubs, you jack up your price in the summer when you are producing more than you use, which further offsets your costs overall.

My system was commissioned August 26th. This is the generation chart. I don't get the sweet self consumption data that Big Time gets, I have to figure it out at the end of the month by comparing the Total Generation, Export and Usage data from my energy bill.

Spoiler!

[Lubicon]

Originally Posted by accord1999

Only if Bigtime could consume all of their production. But self-consumption was only 96.25 kWh, the rest was sold to the grid during the mid-day. And then bought back during the early morning, evening and cloudy days.

Originally Posted by Fuzz

You are forgetting the export of 150kw. Because his production is the daytime when he isn't around to use it, it gets exported. So you have to re-import that 150 plus the 125, for ~275kw.

Bigtime, you really need to do better and re-arrange your consumption patterns to match your generation......

[Bigtime]

That was a solid November thanks to the lack of snow and nice sunny days:

[Calgary14]

Every time I see this thread bumped I want to get solar even more

[Ahuch]

Originally Posted by Calgary14

Every time I see this thread bumped I want to get solar even more

Best get in line, it's getting harder and harder for contractors to get panels/inverters!

[Calgary14]

Looking at solar quotes right now. Isn't the estimated production the most important metric when comparing quotes for different companies? If estimated production is say 6,000 kWh then annual savings would be 6,000 x rate (say $0.06/kWh) = $360 savings per year? Is it that simple or are there more savings Im missing?

[bizaro86]

Originally Posted by Calgary14

Looking at solar quotes right now. Isn't the estimated production the most important metric when comparing quotes for different companies? If estimated production is say 6,000 kWh then annual savings would be 6,000 x rate (say $0.06/kWh) = $360 savings per year? Is it that simple or are there more savings Im missing?

I'd be careful with production estimates. If one company puts up a 10kW array and says it will output way more kWh per year than another company's 10kW array I'd want to know why.

[Calgary14]

^Good point, but assuming they all are around the same production estimate is the estimated savings as simple as 6,000 kWh production x current rate?

[MegaErtz]

Originally Posted by bizaro86

I'd be careful with production estimates. If one company puts up a 10kW array and says it will output way more kWh per year than another company's 10kW array I'd want to know why.

Well, the simple answer is that not all panels are the same. I'm looking at a quote given to a friend for a 6.035kW system, using 17 LG 355 panels, with an estimated yearly production of 7,657 kWh. I live in Los Angeles, which gets about 3,250 hours of sunshine per year, compared to Calgary, which only gets about 2,395.

The LG 355 panels are really good, but really expensive. A quick google search tells me they're going for about $560 CAD plus tax right now. You could get a much cheaper panel that is rated for 355 watts, but what most people don't realize is that no panel will actually produce what it is rated for, even in the middle of the day in the middle of summer with no clouds in the sky. Those wattage ratings are achieved under perfect conditions in a lab.

So company A could offer you a 10kW system for a high price, and it might actually be capable of producing 8kW under great conditions in late June with no clouds in the sky. Company B could offer you the same 10kW system for maybe 75% of the price, but it might only be capable of producing 7kW at any one time, or even less. The premium panels will also produce more in the winter months than the cheap panels.

What kills me is hearing you guys talk as though you actually pay 6c per kilowatt hour. Add up all the transmission, distribution, and paperwork fees plus your cost per Kwh and divide that by your total kWh consumed to get the true cost. If Enmax were actually charging 6c per kWh, nobody would be putting solar panels on their homes. I'm charged 17.4c per kWh for the first 700 kWh every two months, 24c for kWh 701-2100, and 31c for every kWh after that, and I'm still trying to decide if it is worth it.

I recommend checking out a guy named Will Prowse on Youtube if you're serious about having solar installed. The way to go is to install some server rack batteries and store the electricity in them for use after the sun goes down. You get get good 5.12kWh server rack batteries for about $1800 US a pop.

[ken0042]

Originally Posted by MegaErtz

What kills me is hearing you guys talk as though you actually pay 6c per kilowatt hour. Add up all the transmission, distribution, and paperwork fees plus your cost per Kwh and divide that by your total kWh consumed to get the true cost. If Enmax were actually charging 6c per kWh, nobody would be putting solar panels on their homes. I'm charged 17.4c per kWh for the first 700 kWh every two months, 24c for kWh 701-2100, and 31c for every kWh after that, and I'm still trying to decide if it is worth it.

First of all- thank you for that post; lots of good info in there.

Regarding the part I quoted, yes, that is the problem with having the billing broken down the way it is. That is why I wish we were actually billed by the Kwh instead of having line items. While I knew at least some of the line items were based on usage; I didn't know there was a distinction between over/under 700 Kwh. That also explains why I have never been able to figure out the exact math of it; as I'm usually in the ~900 Kwh range.

I guess the bigger question, if you are using a two way meter and putting power back onto the grid, do you get credit based on that? I'm thinking if I could put my 200 Kwh back that is over the 700 mark, in theory that would save me $48 per month. But spending twice as much on a system with twice as much production, would only save me an additional $35.

(And my apologies if I messed up any of the terminology.)

[MegaErtz]

I should be clear, the 700kWh thing is here in Los Angeles, not in Calgary. Sorry for the confusion. Here's a good link to show you the current Enmax rates:

https://www.enmax.com/home/rro/regulated-rates

Most people want a bi-directional meter to feed back into the grid so that they can get that micro-credit. What you're far better off doing is buying the server rack batteries and keeping that extra electricity for yourself, and using it once the sun goes down. The cost has really come down over the last couple of years. You can get a 48v, 100 amp hour, or 5.12kW battery for about $1500 US plus shipping, or an upgraded model with bluetooth for about three hundred more. Here's a good link:

https://www.signaturesolar.com/produ...battery-by-eg4

[timun]

Originally Posted by MegaErtz

What kills me is hearing you guys talk as though you actually pay 6c per kilowatt hour. Add up all the transmission, distribution, and paperwork fees plus your cost per Kwh and divide that by your total kWh consumed to get the true cost. If Enmax were actually charging 6c per kWh, nobody would be putting solar panels on their homes. I'm charged 17.4c per kWh for the first 700 kWh every two months, 24c for kWh 701-2100, and 31c for every kWh after that, and I'm still trying to decide if it is worth it.

Ahhhhh, this is a huge pet peeve of mine. I was talking to one of my coworkers this morning whose power bill was about double what it "normally" is, but she has no idea why because she doesn't really know how to suss out the details of her bill. (Which is actually funny in a sad way, because we do consulting work for Enmax!)

It's a result of the provincial government "deregulating" (I still don't know why we call it that, because it's still massively heavily regulated...) the industry, and our T&D charges, rate riders, etc. not actually being explained in any way as a result. People have no idea how those charges are calculated because it's not actually shown on anyone's bills.

Due to this one just sees lump sum amounts on their bills and won't really know or understand on first glance that most of those extra fees, riders, access charges, etc. are charged on a per-kWh basis.

My last electricity bill covered November 19 to December 17, 2021, and was $53.27. I have a contract for $0.0669/kWh in retail energy charges. That said, the actual per-kWh charges break down like this:

• Energy Charge = $0.0669/kWh
• a portion of the Distribution Charge, the System Usage Charge = $0.012168/kWh
• Transmission Charge = $0.038763/kWh
• Balancing Pool Allocation = $0.002354/kWh
• Transmission Access Charge (TAC; this buried in the rate riders) = ($0.003116/kWh)
• TAC Deferral Adjustment (also buried in rate riders) = ($0.00248/kWh)
• Utility Deferral Adjustment-E = $0.00043/kWh
• a portion of the Local Access Fee (LAF) = $0.018054/kWh

(The math on the LAF is kind of annoying, but basically this is 11.11% of a blend of the regulated rates in November and December apportioned based on the number of days in each month in the billing period, plus 11.11% of the system usage charge... There is also a fixed per-day cost buried in the LAF on top of the above.)

All told, the actual usage rate (to me) is $0.13307/kWh. (Plus about $0.91/day in fixed charges.)

On the Regulated Rate Option (RRO) my bill would have been $63.31, or about 19% higher, with overall per-kWh costs of $0.1805/kWh. And it would be even higher this past month; the RRO in January was $0.15876/kWh, plus a $0.0468/day rider charge. In February the RRO is $0.1652/kWh (plus the per-day charge).

For anyone who's still on the RRO: GO CHANGE YOUR PLAN RIGHT NOW. You're getting reamed on energy charges; if you're with Enmax you can switch over to a $0.0749/kWh 5-year contract, which you can actually switch out of at will over the five years if the rates consistently drop.

[bizaro86]

Originally Posted by MegaErtz

Well, the simple answer is that not all panels are the same. I'm looking at a quote given to a friend for a 6.035kW system, using 17 LG 355 panels, with an estimated yearly production of 7,657 kWh. I live in Los Angeles, which gets about 3,250 hours of sunshine per year, compared to Calgary, which only gets about 2,395.

The LG 355 panels are really good, but really expensive. A quick google search tells me they're going for about $560 CAD plus tax right now. You could get a much cheaper panel that is rated for 355 watts, but what most people don't realize is that no panel will actually produce what it is rated for, even in the middle of the day in the middle of summer with no clouds in the sky. Those wattage ratings are achieved under perfect conditions in a lab.

So company A could offer you a 10kW system for a high price, and it might actually be capable of producing 8kW under great conditions in late June with no clouds in the sky. Company B could offer you the same 10kW system for maybe 75% of the price, but it might only be capable of producing 7kW at any one time, or even less. The premium panels will also produce more in the winter months than the cheap panels.

What kills me is hearing you guys talk as though you actually pay 6c per kilowatt hour. Add up all the transmission, distribution, and paperwork fees plus your cost per Kwh and divide that by your total kWh consumed to get the true cost. If Enmax were actually charging 6c per kWh, nobody would be putting solar panels on their homes. I'm charged 17.4c per kWh for the first 700 kWh every two months, 24c for kWh 701-2100, and 31c for every kWh after that, and I'm still trying to decide if it is worth it.

I recommend checking out a guy named Will Prowse on Youtube if you're serious about having solar installed. The way to go is to install some server rack batteries and store the electricity in them for use after the sun goes down. You get get good 5.12kWh server rack batteries for about $1800 US a pop.

Definitely can be differences in quality of panels for sure. But I've seen quotes using a different amount of solar potential for the same roof - more aggressive weather assumptions don't make one installer any better.

It's stupid that they break the pricing out the way they do (and timun's post above mine is awesome!) But 17.4 cents USD/kWh is more than i pay all-in, and those higher figures are a lot more.

The Alberta power grid is pretty low cost.

[gasman]

Originally Posted by MegaErtz

I should be clear, the 700kWh thing is here in Los Angeles, not in Calgary. Sorry for the confusion. Here's a good link to show you the current Enmax rates:

https://www.enmax.com/home/rro/regulated-rates

Most people want a bi-directional meter to feed back into the grid so that they can get that micro-credit. What you're far better off doing is buying the server rack batteries and keeping that extra electricity for yourself, and using it once the sun goes down. The cost has really come down over the last couple of years. You can get a 48v, 100 amp hour, or 5.12kW battery for about $1500 US plus shipping, or an upgraded model with bluetooth for about three hundred more. Here's a good link:

https://www.signaturesolar.com/produ...battery-by-eg4

This is terrible advice for people in Alberta - Investing in Batteries has no payback. In Alberta we have a system called Solar Club, where you jack up your energy charges to >$0.25/kWh in the summer months when you are a net exporter, earning huge bill credits that pay for your lack of production in the winter, where you switch back to ~$0.08/kWh

Energy price goes both ways, so in the summer if I net export 1000kWh I receive a bill credit of $250. If during that time I took power from the grid during the evenings, or on cloudy days that amounted to 300KWh, I would only have to pay the T&D fees on that power (because the energy charges are offset by production) which might amount to $0.06-0.08/kwh, so I would pay $24 for the imported electricity, leaving me with a total bill of $-226 (bill credit) which I would save up over the summer and then use the credit to float the bill over the winter months.

[gasman]

For some additional thoughts. my system is 10.1kw

From April - September I will produce betwee 1300-1800 kWH/month

My average usage (without solar is) 600-900kWh/month

I self consume about 30% of what I generate

So given an average summer month whereL

I will import 350kWh, self consume 450kWh, and export 1100 kWh

the savings roughly looks like this:

Imported Energy Charge (0.2585/kwh)= $90.48
Exported Energy Credit (0.2585/kwh)= -$284.35
Avoided Energy Charge - Self Consumed ($0.06/Kwh) = -$27 ( I calculate this at the rate I would have, had I not installed solar and just locked in with ATCO)

Imported Energy T&D (simplified as $0.07/kWh) = $24.50
Avoided Energy T&D - Self Consumed (Simplified as $0.07/kWh) = -$31.50

Total: -$227.87

I skipped some of the admin fees, which are fixed daily costs, but the savings are roughly calculated correctly... within 5-10% due to my lazy simplification of the fees.

I can run these types of numbers from April - September generating a bill credit in excess of $1000 at which point I switch back to an importer rate of $0.08/kWh and don't have to pay any bills over the winter months.

In the event I cant "spend my credit" the provider will cut me a cheque if I choose, as long as the credit exceeds $200 for 2 consecutive months.

[Azure]

What is the cost on a 10.1 kw system? Around $30k? That would be a roughly 10 year payback. Not bad if you get 30 years lifespan out of the panels.

[gasman]

Originally Posted by Azure

What is the cost on a 10.1 kw system? Around $30k? That would be a roughly 10 year payback. Not bad if you get 30 years lifespan out of the panels.

I paid Bang on $20K and then got $5k back from the Greener homes grant - This was installed August 2021. so $15K installed

I'm estimating 8 year payback - conservatively, good chance it could be 5 years. I will know more after this summer once I have a full year of run time. Unfortunately my first 6 months of operation are almost all winter.

[Azure]

Ah nice. That is a really good deal then. Here in Manitoba its still 30 years + to pay off any system, and no rebate from the government.

If we want more home owners to go this route, we need cost of solar + installation to go down, plus a better rebate / grant from the government.

[gasman]

Originally Posted by Azure

Ah nice. That is a really good deal then. Here in Manitoba its still 30 years + to pay off any system, and no rebate from the government.

If we want more home owners to go this route, we need cost of solar + installation to go down, plus a better rebate / grant from the government.

I received 4 quotes, all were $2-2.20/Watt. Not sure what the install cost is out your way.

The solar club would be the big one. That cuts my payback in half.

The government grant is federal, so it would be available in Manitoba. I believe it is $1000/kW max of $5k

[Fuzz]

The city has a new calculator:

https://www.calgary.ca/uep/esm/resid...alculator.html

I'm a bit confused though. It says 17 panels is optimal, generating 6245kWh/year. My quick math shows that is about right for generation using factors I've used before, so that's fine.

What I don't understand is the claimed monthly savings is $108. I use ~700kWh per month at a cost of ~$50. They claim I can generate 6245kWh at 6c/kWh divided by 12 months, which gives me ~$31 in electricity savings. How do they get $108?