A Forum run by Enthusiasts of MidNite Solar

General Category => General Discussion => Topic started by: TomW on December 23, 2014, 11:58:16 AM

Title: Researching mounting components for a new solar roof install..
Post by: TomW on December 23, 2014, 11:58:16 AM
We have bought a house in a small town after living in the sticks for most of my life and will be adding a substantial solar energy system. House renovations are underway now.

I have pretty much settled on a system size, inverters and controllers but am up against it on selecting a roof mounting system for 6 KW of panels.

Originally I was gong to use pole mount racks because I need height at the back of the lot to avoid shading in mid Winter from mature boulevard trees I can not or will not butcher.

Decided for the cost of pole mount racks and installation I can build a largish garage / utility building and put the panels on that. Zoning requires a maximum 1,000 square feet and a max height of 16 feet "to the ridge line".

I looked at the Iron Ridge rack / rail system and liked what I saw but would appreciate input from real world installs. Probably looking at a standing seam metal roof (no barn steel allowed)

Thoughts, ideas appreciated.

Thanks.

Tom

Title: Re: Researching mounting components for a new solar roof install..
Post by: xsnrg on December 23, 2014, 07:01:57 PM
Sounds like a wedge roof garage facing S with an ideal roof pitch for your lattitude for the win  8)
Title: Re: Researching mounting components for a new solar roof install..
Post by: xsnrg on December 23, 2014, 07:02:19 PM
Not sure why that posted twice.
Title: Re: Researching mounting components for a new solar roof install..
Post by: TomW on December 24, 2014, 02:27:16 AM
Quote from: xsnrg on December 23, 2014, 07:01:57 PM
Sounds like a wedge roof garage facing S with an ideal roof pitch for your lattitude for the win  8)

That goes without saying.  ::)

The question is what mounting system to use.

Thanks for the feedback.

Tom
Title: Re: Researching mounting components for a new solar roof install..
Post by: toothy on December 24, 2014, 03:07:31 AM
Hello Tom

I've been told I don't play well with others, and I have a problem with rules, look where I wound up building.

So, 1000 sq ft sounds like a footprint restriction, I didn't hear you mention the acceptable length of the overhangs. You could maybe build long overhang so more panels fit further up the roof to deal with your shading issues better.

Look at S-5 clips for the standing seam attachment, I have no personal experience but my brother-in law says their OK. I built all my own racking so can't help with rack manufacturers, but I have a bunch of standing seam and like it.

Wade
Title: Re: Researching mounting components for a new solar roof install..
Post by: TomW on December 24, 2014, 04:56:37 AM
Toothy;

My initial looking makes me think I can get 6 KW mounted on about 500 square feet of roof?

On a 20 by 50 foot building I should easily have that on the long side which will face South.

Haven't done the numbers yet but seems doable with 2 rows of 250 watt panels in portrait orientation at least the Kyoceras I have now would fit 6 KW in that space. I think. Maybe.

I just want to do it once and do it right.

Thanks for the response.

Tom
Title: Re: Researching mounting components for a new solar roof install..
Post by: Halfcrazy on December 24, 2014, 07:12:26 AM
Tom
I am very happy with Iron ridge mounting hardware. If you plan to build a structure I say angle he roof such that the panels simply mount flat on the roof and will be at the proper titl already. One piece of advice I will give you is if you can keep the panels out flush with the drip edge on the lower side. This way the snow will fall off as it starts to slide.

As far as space these new panels are pretty powerful they are averaging around 16 watts per square foot so with a 1000SF you should be all set.

Ryan
Title: Re: Researching mounting components for a new solar roof install..
Post by: TomW on December 24, 2014, 02:32:29 PM
Quote from: Halfcrazy on December 24, 2014, 07:12:26 AM
Tom
I am very happy with Iron ridge mounting hardware. If you plan to build a structure I say angle he roof such that the panels simply mount flat on the roof and will be at the proper titl already. One piece of advice I will give you is if you can keep the panels out flush with the drip edge on the lower side. This way the snow will fall off as it starts to slide.

As far as space these new panels are pretty powerful they are averaging around 16 watts per square foot so with a 1000SF you should be all set.

Ryan

Ryan;

Appreciate the input on the Iron Ridge rack system.

Great idea on the snow dropping off past the drip edge.

I am getting conflicting information online regarding fixed tilt angle panels by latitude.

Everything from formulas to the latitude itself depending on the source. The system  will be at     41° 46′ N, 91° 7′ W and I am leaning towards 42 degrees fixed tilt as it aligns with my thoughts on it before I got confused by online "sources". All of my previous systems were adjustable for seasonal tilt and I just eyeballed it every few months.

Maybe I need to hire a pro to design the system? Nah, it ain't rocket science its merely trigonometry.

Appreciate everyone's input.

Tom

Title: Re: Researching mounting components for a new solar roof install..
Post by: xsnrg on December 25, 2014, 12:07:06 AM

When I designed my structure, I searched around a lot to figure out what a good angle was as well.  I ended up going through the math from http://www.solarpaneltilt.com/ (http://www.solarpaneltilt.com/) .  The research seems to be there to support how ever you want to set it up, whether that is max in the winter, max across the whole year, etc.  The only other change I envision would be a single axis polar tracking system.  It gets you a good chunk of 2 axis power with a lot less complexity.

Jim
Title: Re: Researching mounting components for a new solar roof install..
Post by: SolarMusher on March 06, 2015, 02:38:44 PM
Hi Tom,
A little late on this post, but here's an ironridge flush mounted array on a 45° metal roof that I've done a few years ago. I'm not sure if snow could be a problem for you, but a good idea would be to build a rig like on pic to access to the panels if you need to clean them.
Do not forget that even though a 45° angle, snow will stick to your panels.
Good luck,
Erik
Title: Re: Researching mounting components for a new solar roof install..
Post by: TomW on March 06, 2015, 04:08:51 PM
Quote from: SolarMusher on March 06, 2015, 02:38:44 PM
Do not forget that even though a 45° angle, snow will stick to your panels.
Good luck,
Erik

Yep, mine are at a lot steeper angle, say 60+ degrees this time of year (adjustable) and snow sticks pretty well. Usually a good rap on the pole mount frames loosens it but it is an issue sometimes.

Patiently awaiting the snow meltt feature on Classics.  :o

Thanks to all of the responders.

Tom