Power from solar tiles seems crazy high

[fehguy]

OK so I got my solar tile roof back in Feb and the team did a fantastic job putting it on. Granted it took longer than expected but the end result is better than I was hoping for. There were some changes in the electrical scheduled prior to final permitting when... COVID came along. So I have a finished roof over my head, but I'm technically not "on the grid". I have no data in the Tesla app yet because it hasn't been finaled.

Well I wanted to try things out so I turned it on and it works! And I have numbers that seem pretty much insanely high. I wanted to see if I'm reading this the wrong way.

I have two inverters, one for each side of my roof. From the picture, the visible side gets the morning sun. The opposite side (which is uninterrupted because it has no dormer window) gets the afternoon sun.

If I'm looking at the data the right way, I'm consistently getting > 40kWh generation per day! The specs said it'd be just over 10kWh. What's wrong (or right)??? Of course I turned it off after a few days of testing...

 

[power.saver]

I suspect you are confusing 10kW with 10kWh. The 10kW is your solar roof size, and production can be close to 40kWh per day.

 

[jrweiss98020]

My 9 KW array generates about 60 KWh/day peak, so your 40 KWh is about right with all the shading.

 

[fehguy]

Right you are. Looking at the design, it looks like the estimate would be about 23kWh daily average so the numbers seem right.

Thanks!

 

[jjrandorin]

OP, I suspect what @power.saver says is what is going on here....

For reference, I have tesla solar panels (not solar roof) and my system size is 8.7, but I see production right now (from late march through june or so) of roughly 50-52 Kwh per day on a nice sunny day.

Edit : we were posting at same time.

With that being said, I find the numbers somewhat interesting, at showing how shading etc can really affect production (and roof pitch). My 8.7 sized system produces annual Kwh of around 12,500 or so.

 

[getakey]

actually 40 kWh seems low. I don't have solar roof, but 11 kW solar panel system. Today I generated 67 kWh. My panels face East and West, but roof is not as steep

 

[jboy210]

We are also still waiting for final inspection and PTO on our Solaglass roof, but I noticed during "tests" that the roof generates a lot of power (mine is a 12.2 KW). And I think a lot of it comes from the North facing side of the house. The sections where they put the active tiles on the North side are in sun a lot. So the program that Tesla uses to position these tiles is quite accurate. It is nice to see the 2 PWs get filled in a 3-4 hours. Can't image how much power we will generate in summer. Maybe I should add another powerwall to capture more.

 

[patrick40363]

We are also still waiting for final inspection and PTO on our Solaglass roof, but I noticed during "tests" that the roof generates a lot of power (mine is a 12.2 KW). And I think a lot of it comes from the North facing side of the house. The sections where they put the active tiles on the North side are in sun a lot. So the program that Tesla uses to position these tiles is quite accurate. It is nice to see the 2 PWs get filled in a 3-4 hours. Can't image how much power we will generate in summer. Maybe I should add another powerwall to capture more.

How much is your roof generating? I am going to get a 12kw roof which is more than the 9.5kw Tesla had on my order.

 

[jboy210]

How much is your roof generating? I am going to get a 12kw roof which is more than the 9.5kw Tesla had on my order.

Around 8-9 total KW in beginning of April. I assume it will go up as summer progresses.

 

[jboy210]

View attachment 534884

View attachment 534885

I wish our inverters had displays to give you this type of information.

 

[msm859]

actually 40 kWh seems low. I don't have solar roof, but 11 kW solar panel system. Today I generated 67 kWh. My panels face East and West, but roof is not as steep

Agreed I have. @10.5 kW and have been getting over 60 kWh production.

 

[emoore33]

Agreed I have. @10.5 kW and have been getting over 60 kWh production.

Do you have a solar roof or just solar panels? Am 11kW solar roof will have less production than 11kW of south facing solar panels.

 

[getakey]

just because you have panels versus roof doesn't mean they are facing South. I have 40 Panels (11.8kW). My roof faces East and West. I have more panels on the East roof than on the West roof just due to roof structure. On Tuesday, I produced 67kWh. Yesterday was 64kWh

 

[Racerx22b]

I have an 11.69kW system and my max daily production on a southern facing roof with no interruptions (basically a perfect day) of exposure is around 70kWh for a single day. I am located in south FL and have panels (not solar roof).

 

[Massive Attack]

OK so I got my solar tile roof back in Feb and the team did a fantastic job putting it on. Granted it took longer than expected but the end result is better than I was hoping for. There were some changes in the electrical scheduled prior to final permitting when... COVID came along. So I have a finished roof over my head, but I'm technically not "on the grid". I have no data in the Tesla app yet because it hasn't been finaled.

Well I wanted to try things out so I turned it on and it works! And I have numbers that seem pretty much insanely high. I wanted to see if I'm reading this the wrong way.

I have two inverters, one for each side of my roof. From the picture, the visible side gets the morning sun. The opposite side (which is uninterrupted because it has no dormer window) gets the afternoon sun.

If I'm looking at the data the right way, I'm consistently getting > 40kWh generation per day! The specs said it'd be just over 10kWh. What's wrong (or right)??? Of course I turned it off after a few days of testing...

View attachment 534883

View attachment 534884

View attachment 534885

Your roof came out looking really well! Congratulations!

 

[msm859]

Do you have a solar roof or just solar panels? Am 11kW solar roof will have less production than 11kW of south facing solar panels.

I have solar panels 16 facing 122 degrees, 16 facing 212 degrees and 3 facing 302 degrees. Although pure south might give you higher production, given peak pricing periods there is a benefit to facing south-west.

 

[getakey]

I can get 70 to max of 78 per day in the summer
Heat keeps the production down even though hours of sun is longer

 

[WatcherXP]

Sounds about right, my 10 kWp system generates about 63-65 on a "perfect" day, i expect that to trend upwards as the summer rolls along.

 

[Sonus]

Interesting, I have a 7.56Kw system and I am generating over 40KW on a sunny day. I always thought that I am on the low side and when summer comes it will generate more. From the looks of things, the system is solid.

 

[getakey]

I think you benefit from being a bit cooler in the summer
we are outside of Sacramento and get to 100+ often