Poor solar panel install locations?

[h2ofun]

As I drive around, i tend to look at roofs for solar panels now. I look at them relative to mine, where half are south facing with limited tree issues, and my west facing, which this time of the year do not get a lot of sun.

What I am amazed at is how many panels I see located in places with things like lots of trees around that shade, or in such
a location that they would seem to get little sun, even in the best of months.

I remember talking to a person who had tesla panels installed and said they basically are getting little benefit , like OA she said cost more money with the loan, since the trees do so much shading.

So, do solar installers really install panels in locations that really make the panels maybe never pay for themselves just to make money? I have a neighbor who bragged about his solar he installed would cut his bill to zero. Of course, this never happened. And worse, he basically installed them where they mostly get shade from huge trees next door to him.

 

[run-the-joules]

As I drive around, i tend to look at roofs for solar panels now. I look at them relative to mine, where half are south facing with limited tree issues, and my west facing, which this time of the year do not get a lot of sun.

What I am amazed at is how many panels I see located in places with things like lots of trees around that shade, or in such
a location that they would seem to get little sun, even in the best of months.

I remember talking to a person who had tesla panels installed and said they basically are getting little benefit , like OA she said cost more money with the loan, since the trees do so much shading.

So, do solar installers really install panels in locations that really make the panels maybe never pay for themselves just to make money? I have a neighbor who bragged about his solar he installed would cut his bill to zero. Of course, this never happened. And worse, he basically installed them where they mostly get shade from huge trees next door to him.

Yeah I've been noticing the same thing recently, and in fact a few friends are now looking at solar and I've shown them a few examples of bad ideas vs good ideas for their house. One friend's house is great for it if he's willing to sacrifice an enormous old tree to the southwest of his house.

 

[run-the-joules]

Wow, just randomly zooming around on Google Maps and found this, ouch:

 

[israndy]

There are two things I would say:

1) Trees grow, solar panels are immovable. There may not have been any solar issue when you first installed the panels

When I installed my panels I looked at the sun and remembered how low the sun gets in the winter (I thought) and finished the install in August. By October I was getting shading that I could see moving across the panels as the day progressed. I paid some tree guys to come and top my trees to be about in line with the roof. Yet by November, I was seeing shading again. OK, so it only lasted a couple of months, but it was disappointing.

2) Just because you get shadows at some point doesn't mean the solar won't eventually pay for itself

I still have 99% of the time w/o any shading, and my most productive days are in the summer anyway. Sure there are times when you will see shadows on solar panels, my roof has no southern exposure, so I put panels on both sides, in the AM the eastern panels wake up first, but I have generation until sundown, and they are actually the panels I get the most generation from despite this area being famous for morning fog.

Sure it sucks to have a chimney or a neighbors tree shading your panels, but they are WAY better than nothing. They could be expensive at first but you know what's really expensive?

 

[run-the-joules]

They could be expensive at first but you know what's really expensive?

Income taxes!

 

[Kodemonkey]

I got lucky, my neighbor had a tree shading my roof (actually hitting it). I told him I was putting in solar and he said that now it gives him the excuse to remove the tree because it is tearing up his patio. So now I have zero trees that will shade. I have 14 panels on a 14 degree slope due west and 14 panels on a 14 degree slope pointing due east. When I ran the calculations I came almost to the exact yearly KW generation that Tesla and Sunrun came up with. They just re-did my plans (long story) and somehow my yearly generation went up to from 13,733KW to 14,442KW (9.5KWh system).

 

[zƬesla]

Wow, just randomly zooming around on Google Maps and found this, ouch:

2) Just because you get shadows at some point doesn't mean the solar won't eventually pay for itself

My pole-mounted panels get tree shade in winter for part of the day. On good days I get over 100kWh in summer and around 30-40kWh in winter (although averaging closer to 20 the past month due to weather).

I wouldn't base a decision on a single satellite photo showing shade without understanding when it occurs and for how long.

 

[run-the-joules]

My pole-mounted panels get tree shade in winter for part of the day. On good days I get over 100kWh in summer and around 30-40kWh in winter (although averaging closer to 20 the past month due to weather).

I wouldn't base a decision on a single satellite photo showing shade without understanding when it occurs and for how long.

holy shnikes. How big is your system‽

 

[zƬesla]

How big is your system‽

17.5kW with two inverters (7.7 and 7.0)

 

[run-the-joules]

17.5kW with two inverters (7.7 and 7.0)

That's *awesome*

 

[jboy210]

We have shading. Nothing we can do about it. 60-foot oak tree was there first, 100 years ago. The city will not let us touch it except to trim it.

The shading is getting a little less now that the leaves are falling off. But we are still only generating 7-8 kWh/day on a 12.75 kW roof. When the sun gets higher in Spring we should close in on 100 kWh/day. House is at 181 degrees so a number of tiles face due South. But we also get power from the East and North facing tiles.

 

[run-the-joules]

We have shading. Nothing we can do about it. 60-foot oak tree was there first, 100 years ago. The city will not let us touch it except to trim it.

The shading is getting a little less now that the leaves are falling off. But we are still only generating 7-8 kWh/day on a 12.75 kW roof. When the sun gets higher in Spring we should close in on 100 kWh/day. House is at 181 degrees so a number of tiles face due South. But we also get power from the East and North facing tiles.

man, 100kWh/day would be wild. I don't have the faintest idea how much I'll realistically generate once we get to spring and summer, but if I can average above 30/day for the whole year that'll go a long way towards covering all of my usage (notwithstanding NBCs and things because of the TOU crap in general, but I'll try to get powerwalls next year to take care of THAT issue)

 

[jboy210]

man, 100kWh/day would be wild. I don't have the faintest idea how much I'll realistically generate once we get to spring and summer, but if I can average above 30/day for the whole year that'll go a long way towards covering all of my usage (notwithstanding NBCs and things because of the TOU crap in general, but I'll try to get powerwalls next year to take care of THAT issue)

While "testing" in May or June we generating 55-60 kWh by 2-3 PM. At that point I was running out of places (Model X is thirsty, but not that thirsty) to put electrons so was shutting off the inverters. With tiles pointing East, South, North, and few West during May and June the system generates power from 7 AM to 7PM or later.

 

[jboy210]

man, 100kWh/day would be wild. I don't have the faintest idea how much I'll realistically generate once we get to spring and summer, but if I can average above 30/day for the whole year that'll go a long way towards covering all of my usage (notwithstanding NBCs and things because of the TOU crap in general, but I'll try to get powerwalls next year to take care of THAT issue)

You can look at the calculator at PVWatts Calculator to get a rough estimate at generation for each month of a specific panel layout at your address.

 

[jsmay311]

A reputable installer should do a shade analysis and be honest with the customer about how much energy they stand to lose due to shading. But I wouldn't be surprised if less reputable installers gloss over these important details.

My installer used a Solar Pathfinder device to determine how much shade different parts of my roof would get in different months and at different times of day, and that helped guide my decisions on overall array size/layout and on selecting microinverters over a string inverter.

 

[israndy]

Yeah, I got the same treatment by 3 different solar installers over the years. None of them thought it was worth doing with the lack of southern exposure.

Most of my Craigslist panels point more north than south, but I have still generated 11 megawatt/hours in the last year. At 28¢/kWh here in Alameda I am almost done paying off my initial investment of just about $5000, then all the extra power will be free. I sure enjoyed all those negative bills from the power company from April to October, just got my second bill I have to pay and it's finally substantial at $89.

Kinda painful that we just spent the weekend hanging XMAS lights, January's bill will certainly be worse. I should figure out a way to plug them into my car so they run off the stored energy.