Mythical $3.50/watt installation?

[ButchDeal]

With 16' of roof, you "might" be able to extend the top row 6" above the top but you would only get 18 panels or 5.4KW.

I would really look a bit harder at ground mount if you have the space and good sun exposure. You can do much of the footing work with 2" galv pipe yourself and rent or borrow a backhoe to do the trenching. If you are handy you can do most of the installation too - its just mechanical work.

The other benefit of ground mount is you can clear the snow off in the winter easily too - that's the biggest impact on power production in my opinion - my output in Jan & Feb was 300KWH total, then March no snow and nearly 800KWH. There are several solar edge installations ground mount in the area I have checked over the winter and they produce very well year round.

So you might be able to install say 24 300W panels to get 8.1KW and get better overall performance year round since snow can "rob" you of maybe 1000-1200 KW hr a year (that's what I figure to lose) - or about $220 a year at current rates.

Good luck!

Carl

Ground is going to add a bit of cost in materials ( pipe, wire, and cement ) as well as labor (trenching, footings, rack assembly ). And in many areas requires fencing around back side at least.
Once you are into ground mount there is little point in high efficiency just add a few more modules.

[Carl_NH]

Carl,

My install probably wouldn't be quite as straightforward as yours. My garage roof does face due south, and tilted at about 45 degrees, but it's not big enough for the entire system. The roof is inconveniently exactly 16 feet "tall" (the straight-line distance from edge to ridge, not the vertical distance). It seems that most panels are 5.5 feet tall, so three portrait rows would require 16.5 feet. The roof is 22 feet long. So it seems that at best I could fit 15 panels on it - two portrait rows with six in a row, and then a row of three in landscape orientation. The rest will need to be split between the roof of the sunroom/addition I built (roof faces due south also, but we could probably only use a third of the roof since the rest experiences shading from the main part of the house), and a ground mount array.

One option I've been pondering instead of a ground mount array
Mike

With 16' of roof, you "might" be able to extend the top row 6" above the top but you would only get 18 panels or 5.4KW.

I would really look a bit harder at ground mount if you have the space and good sun exposure. You can do much of the footing work with 2" galv pipe yourself and rent or borrow a backhoe to do the trenching. If you are handy you can do most of the installation too - its just mechanical work.

The other benefit of ground mount is you can clear the snow off in the winter easily too - that's the biggest impact on power production in my opinion - my output in Jan & Feb was 300KWH total, then March no snow and nearly 800KWH. There are several solar edge installations ground mount in the area I have checked over the winter and they produce very well year round.

So you might be able to install say 24 300W panels to get 8.1KW and get better overall performance year round since snow can "rob" you of maybe 1000-1200 KW hr a year (that's what I figure to lose) - or about $220 a year at current rates.

Good luck!

Carl

[J.P.M.]

Carl,
Thanks for the detailed response. I'll give that company a call to get an estimate from them. It's always good to know that somebody had a good experience with a company before committing to a large contract with them.

My install probably wouldn't be quite as straightforward as yours. My garage roof does face due south, and tilted at about 45 degrees, but it's not big enough for the entire system. The roof is inconveniently exactly 16 feet "tall" (the straight-line distance from edge to ridge, not the vertical distance). It seems that most panels are 5.5 feet tall, so three portrait rows would require 16.5 feet. The roof is 22 feet long. So it seems that at best I could fit 15 panels on it - two portrait rows with six in a row, and then a row of three in landscape orientation. The rest will need to be split between the roof of the sunroom/addition I built (roof faces due south also, but we could probably only use a third of the roof since the rest experiences shading from the main part of the house), and a ground mount array.

One option I've been pondering instead of a ground mount array is if we could put a tilted array on the back roof of the main house. The main roof faces west, but is not tilted much (maybe 15 degrees?), so it seems like we could put at least one row on a tilted rack.

Mike

Tilted (non parallel to mounting surface) mountings can and are done. Sometimes/often, the added production is not worth the added cost, and such arrangements need additional consideration(s) for wind loadings and perhaps other things like snow drift buildup etc. all of which may make such arrangements non cost effective, but not as unusual as you might think.

On roof space, you will need room for access and servicing.

If space is available, ground mounts offer the most flexibility but add to the cost. The no free lunch thing.

[DrBriggs]

Carl,
Thanks for the detailed response. I'll give that company a call to get an estimate from them. It's always good to know that somebody had a good experience with a company before committing to a large contract with them.

My install probably wouldn't be quite as straightforward as yours. My garage roof does face due south, and tilted at about 45 degrees, but it's not big enough for the entire system. The roof is inconveniently exactly 16 feet "tall" (the straight-line distance from edge to ridge, not the vertical distance). It seems that most panels are 5.5 feet tall, so three portrait rows would require 16.5 feet. The roof is 22 feet long. So it seems that at best I could fit 15 panels on it - two portrait rows with six in a row, and then a row of three in landscape orientation. The rest will need to be split between the roof of the sunroom/addition I built (roof faces due south also, but we could probably only use a third of the roof since the rest experiences shading from the main part of the house), and a ground mount array.

One option I've been pondering instead of a ground mount array is if we could put a tilted array on the back roof of the main house. The main roof faces west, but is not tilted much (maybe 15 degrees?), so it seems like we could put at least one row on a tilted rack.

Mike

[DanKegel]

I didn't mean equipment vendors, I just meant installers.
In http://www.solarpaneltalk.com/showth...l=1#post139070, SolarPete said
"Please note I work for the same crew (well sort of) that runs this site and solar reviews, cheers and good luck with it, hopefully some more knowledgeable people from your area will chime in, and no its not cool to mention installers names here."

[Carl_NH]

You might want to edit out those vendor names. Board policy is not to name installers except in private messages.

Respectfully, I think the board policy is not to provide web links and or direct contact information about the vendors, but to mention the supplier is acceptable.

This forum is not the place for the suppliers or vendors to hawk their goods is the intent I believe.

I have not seen or witnessed the mention of the installer or supplier to be objectionable, if so reference to Solar City, LG, Solar Edge, Sun Power or any supplier would be an issue.

[DanKegel]

You might want to edit out those vendor names. Board policy is not to name installers except in private messages.

[Carl_NH]

Carl, who did your install? I'm in nearby Dover, and have started getting estimates on an 8 kw system. The first one came in at $5 per watt!!! So I'd love to know who did yours.

Thanks!
Mike

Mike,

Revision Energy did ours - it was a very straight forward install on our garage roof and roughly 20' of electrical runs. The reason I state this is every installation is different -needing electrical panel upgrades, installing on two roof areas and more will impact the $ per watt.

Before I went out to quote I did the PV Watts calculation, then a current usage cost analysis and put a reduction plan in place (LED lighting, and longer term mini split heat pump) then did a fairly detailed assessment of materials and general assumptions on labor. I also had a friend that installed a system from Revision too, so I knew (they did too) what to expect $ wise.

So going into the quote process I sent the general requirements/goals to three companies in late August last year and signed a contract late September. Since that time, I have heard Revision pricing has increased but they will be competitive and they do a quality installation.

Do your homework, get some estimates, and gain knowledge - like on here and talk to other people too.

Carl

[DrBriggs]

Carl, who did your install? I'm in nearby Dover, and have started getting estimates on an 8 kw system. The first one came in at $5 per watt!!! So I'd love to know who did yours.

Thanks!
Mike

[Carl_NH]

Installed 7.2KW - 21 LG300 and SE optimizers December 2014

$26,100 or $3.62/watt

State & Federal Rebates $11,700.

Net Cost $14,400 or $2/watt

Real Cost Assumptions:

40 Man hours on Site @ $80 burdened rate $3200.

Permitting / Paperwork Process by vendor $1000.

Material Cost $15,000.

Total Vendor Cost $19,200

Vendor Profit $7000

DIY Installation

Since PV is "new" here there are not many electricians that will sign off on a DIY General Contractor installation or roofers that install solar panels but if they did here is what I believe will be the "future costs" once mainstream:

Materials $16,000.

Electrician $1000 - 10 hours $100/hour

Roof Installation $2500 - 25 hours $100/hour

Misc Hardware Materials $500.

Total Installed Cost $20,000

Last, cost/watt is regional based on demand, and as many other posts have stated, PV solar can be installed easily and inexpensively.

Carl

[DanKegel]

$2.70 a watt is the lowest I've seen from a major company.

Wow. What city, kw, and panel type?

I just got a quote for $3.47/watt cash before rebates for an 8.8 kw system in urban Los Angeles (25 lg305's plus 4 gxb300's, two of which are reverse tilt mounted, all on a sloped roof). $2.20/watt after rebates. I expect it to generate about 35kwh/day avg. Naive payback time is about 10 years if grid power is $0.16/kwh, 7 years if it's $0.20/kwh. This is from a small local installer.

[KRenn]

Amazing how much more expensive California solar is. Here in AZ we are doing cash purchase deals at $3.10/watt installed.

$2.70 a watt is the lowest I've seen from a major company.

[J.P.M.]

But most of the added cost in the U.S. are the soft costs originating from unsustainable business practices in an immature solar market.

With those business practices supported by tax credits that allowed vendors to charge higher prices and thus keep going who would never have started much less survived in a fair market.

[donald]

I wasn't making a case for Moore's Law with solar. I was making the a case for a technology product where steady price/performance improvement is expected. If you are the CTO of a panel manufacturer and can't convince the board that you have a three year plan of price/performance improvements you will not have a job.

From the article I posted:

Panels to fall in price to $US0.50/watt

Deutsche Bank says that while overhangs like trade cases or minimum price agreements could cloud the near term, market inefficiencies will be worked out over the long term and the clearing price will reach $0.50 or lower within the next several years.

Companies like SunEdison have publically targeted $0.40 cent per watt panels by the end of 2016, and many Tier 1 Chinese manufacturers are achieving sub $0.50/w already in 2014. :Given that most manufacturers are improving 1-2 cents per quarter, less than ten cents improvement (to reach $0.40) over the next 12 quarters is likely conservative.

If panels are sold at a 10 cent gross margin for a total cost of $0.50/w, manufacturers would achieve 20% gross margin – well above recent historic averages. Furthermore, transportation costs and ‘soft costs’ which inefficiently raise the price of panels should gradually improve as governments work through trade issues

[paris401]

A good example of using all/most of the available tools.

when I put in panels at my sons home, the solar company will take up to 10k on credit cards... so I used 3cards... got $800 bucks from from chase, and 50k of American airline points, good for '2' first class upgrades from san diego/ny ...

will do the same thing when I install panels at my home..