Solar Shingles

Steven Lake

http://www.thisoldhouse.com/toh/article/0,,1205726,00.html

Just heard about these today. What do you guys think of them? To me they seem like an interesting idea. Certainly a lot more space efficient than regular panels. The only real questions are cost per module vs regular solar panels, output per square foot and durability, which I have yet to find any numbers on.

BB.

Re: Solar Shingles

They did not list a vendor (that I saw)--In any case, I would want to look at the details. Connecting electrically, how rugged they are over 20+ years, etc. all were a concern with many of the other solutions (hard to beat glass as a solar panel cover/base for silicon cells).

Most of the previous versions I have seen (I am not in the business) used plastic (flexible panel) technology. Getting more than 2-10 years of life is usually pretty good.

Just my concerns--I am not in the business and have never seriously researched BIVP type panels. Your mileage may vary.

-Bill

jaggedben

Re: Solar Shingles

Frankly, I think this stuff is dumb.

To begin with, in general I just don't buy the notion that regular solar panels are ugly and that these BIPV solutions look better. Are asphalt shingles pretty? Are concrete tiles pretty? Are the vents and chimneys and skylights on most residential roofs pretty? Does anyone who is not a roofer or a solar contractor ever even notice what's on your roof? The reasonable answer to all those questions is no, in my admittedly not-so-humble opinion. The primary reason that a minority of people believe solar panels are ugly is because it's a new thing they are not used to seeing. Once solar becomes common enough, I believe, that notion will fade away almost completely.

That is not to say that solar installations are never ugly. But if they are, then without exception it's because of things that a BIPV solution doesn't solve. For example, a reverse tilt-up may be ugly. BIPV isn't a solution for that. Poor workmanship may produce ugliness. BIPV isn't a solution for that either. Silver frames and white back film can look uglier. There are black panels that look better.

So 'solar shingles' are a solution that is mostly searching for a problem. But beyond that there are practical and economic problems...

- "Shingles" and "tiles" are small things compared to 60 cell solar panels. Simply put, they aren't good units with which to design a solar system, either for string inverters or microinverters.
- With BIPV if you have an electrical problem with your solar you have to compromise the waterproofing on your house to fix it. With non-BIPV systems that's not an issue.
- If the BIPV system ends up being having poor waterproofing qualities and you decide it needs to be replaced, you end up loosing your solar system when you redo your roof.

That is not to say that BIPV doesn't have it's place. But its best applications are probably in new construction, where the entire roof and supporting system can be designed and built from scratch with solutions in mind to the problems above (e.g. access from below to the electrical parts). That is to say, if people are willing to rethink roof systems enough, it could become a new way of doing things. But forget 'solar shingles' as a replacement for asphalt shingles on traditional roof systems. It's not a worthy idea.

Thanks for reading, and I'll step off my soapbox now...

peakbagger

Re: Solar Shingles

Keep in mind, this Old House is basically paid for every product mentioned on their TV show and their magazines. They and other shows hide behind a PBS logo but they aren't non profits. Given that background, prior attempts at solar shingles have not been very successful as the labor associated with installing them is generally quite high as each shingle is usually fairly low wattage. Unless the product mentioned is a radical new design, I expect that the cost per watt is quite high making the payback long.

mike95490

Re: Solar Shingles

Steven Lake wrote: »

.... The only real questions are cost per module vs regular solar panels, output per square foot and durability, which I have yet to find any numbers on.

Hey sheep, Don't start asking real questions

http://www.sunslates.net/ - faux "Slate" shingles with tempered glass PV panels glued to them. From http://atlantisenergy.com/?page_id=255
22watts per shingle - http://atlantisenergy.com/wp-content/uploads/2011/07/Sunslates-6-spec.pdf

Cariboocoot

Re: Solar Shingles

I heard about these back in the 1970's, from This Old House.

Since then they've been 'announced' over and over again.

So instead of a 5' x 3' panel producing 300 or so Watts you get something the size of a 3-tab roof shingle, and a lot of connections to make.

I'll pass.

Steven Lake

Re: Solar Shingles

Well, I'm more interested in them for the projected power density. IE, 10 watts per 6" square inches rather than 10 per 160. My interest in the greater energy densities is having 300 watts in a 20 watt footprint (which I'm kinda hoping these shingles, if perfected, might some day achieve) allowing me to put up one panel about the size of today's 350w and suck in power in the 2k+ range. Probably wishful thinking given known material efficiencies, but one can dream, no?

jaggedben

Re: Solar Shingles

I have no idea where you are getting those numbers from. There's definitely no reason to believe that solar 'shingles' will be more efficient than full size panels.

ggunn

Re: Solar Shingles

Steven Lake wrote: »

Well, I'm more interested in them for the projected power density. IE, 10 watts per 6" square inches rather than 10 per 160. My interest in the greater energy densities is having 300 watts in a 20 watt footprint (which I'm kinda hoping these shingles, if perfected, might some day achieve) allowing me to put up one panel about the size of today's 350w and suck in power in the 2k+ range. Probably wishful thinking given known material efficiencies, but one can dream, no?

Let's see now...

There are about 1550 square inches in a square meter. Benchmark solar is 1000 W/m^2, which is about .64W/in^2. For 6 square inches, that's less than 4W. 10W per 6 in^2 is 258% efficiency. That's pretty good. ;^)

But perhaps you mean 6 inches square instead of 6 square inches. So that would be 10W per 36 square inches. (36)(.64W/in^2) = about 23W of incident energy. 10W/23W = 43% efficiency, which is still way over the efficiency of crystalline silicon (typically 14-17%). Aren't solar shingles thin films? Thin films are generally a good deal less efficient than silicon.

I think your numbers are far off the mark in any case.

Cariboocoot

Re: Solar Shingles

And if you could produce solar shingles with such amazing efficiency could you not also produce solar panels capable of the same numbers? Would you not do so first? The configuration of a panel has no affect on its efficiency, but does factor largely in its practicality.

BTW, This Old House gets all these wonderful products donated in exchange for the free advertising.

SolarPowered

Re: Solar Shingles

HAHA the article says "then an electrician(or trained roofer) has to wire the units together".

I will never in my life time, see a california C39 roofer do the job of a california C10 electrician, or C46 solar installer. There are roofing companies that install solar, however if they only have a C46 classification installer they can only install the DC side of the system, a C10 can install the entire system. A california C39 alone CANNOT install solar or electrical at all!!!!

The article is just a sales gimmick to get people to buy a product that cost 50% more than standard panels.

jaggedben

Re: Solar Shingles

SolarPowered wrote: »

... if they only have a C46 classification installer they can only install the DC side of the system ...

That's not true.

The article is just a sales gimmick to get people to buy a product that cost 50% more than standard panels.

Agreed.

SolarPowered

Re: Solar Shingles

jaggedben wrote: »

That's not true.

How much you willing to bet with my years of experience, consulting, and buying insurance policies, and being a class B contractor?
A c46 can only install AC line side, if that C46 has a CERTIFIED C10 electrical installer. In California you have to be certified C10 to handle line side taps, AC, and breakers. C46 can pull strings and combine but that's as far as installation goes, the rules are bent little on micro inverter as the install can happen to the point of disconnect.
No where on the CSLB C46 examination does the testing express line side tapes, or point to breaker installs.

Cariboocoot

Re: Solar Shingles

SolarPowered wrote: »

HAHA the article says "then an electrician(or trained roofer) has to wire the units together".

I will never in my life time, see a california C39 roofer do the job of a california C10 electrician, or C46 solar installer. There are roofing companies that install solar, however if they only have a C46 classification installer they can only install the DC side of the system, a C10 can install the entire system. A california C39 alone CANNOT install solar or electrical at all!!!!

Just a reminder: not everyone lives in California. And boy are they who don't glad of the fact.

SolarPowered

Re: Solar Shingles

Cariboocoot wrote: »

Just a reminder: not everyone lives in California. And boy are they who don't glad of the fact.

I agree, too many bureaucratic liberals that feel they need a piece of the pie....

California needs less government, less lobbyist, less bureaucracy.

Last I checked the state of California CSLB website including my class B license there are now 66 classifications for licenses. Most states only have 40 classifications or less. That's how ridiculous and redundant the classification structure is. Now the only reason why there are so many classifications is because consumer affairs wants to generate more money on licensing fee's, insurance companies want to adhere additional insurance policies, and the CSLB wants to crack down on contractors that exceed the limitations of their practice and fine them.

Its a disgusting joke.

If you look at the bottom, the HIC classification was repealed, I lobbied to repeal it because it was just a redundant classification for a class B like myself that is more than qualified for the job, yet it was a classification that would prohibit my classification from doing Home Improvement work, it was repealed in 2004.

http://www.cslb.ca.gov/GeneralInformation/Library/LicensingClassifications/

jaggedben

Re: Solar Shingles

SolarPowered wrote: »

How much you willing to bet with my years of experience, consulting, and buying insurance policies, and being a class B contractor?

If the terms of the bet are that C46 contractors are in fact doing AC side work everyday in California, and not getting stopped or fined for it by authorities, but rather their installations are getting approved by AHJs and signed off by utility interconnection departments, then I'm willing to bet all the money I earned working for a contractor who did exactly that. 8)

A c46 can only install AC line side, if that C46 has a CERTIFIED C10 electrical installer. In California you have to be certified C10 to handle line side taps, AC, and breakers. C46 can pull strings and combine but that's as far as installation goes, the rules are bent little on micro inverter as the install can happen to the point of disconnect.
No where on the CSLB C46 examination does the testing express line side tapes, or point to breaker installs.

The contents of an exam are not legally binding. Show me where in the law it says a C46 can't install a breaker.

http://www.cslb.ca.gov/generalinformation/library/licensingclassifications/c46solar.asp

I'd agree that a line-side-tap should be done by a C10, but I'm not even actually sure if it's required under that language.

BTW are you saying that a C46 can't install micro-inverter cabling because it's AC?

SolarPowered

Re: Solar Shingles

jaggedben wrote: »

The contents of an exam are not legally binding. Show me where in the law it says a C46 can't install a breaker.

http://www.cslb.ca.gov/generalinformation/library/licensingclassifications/c46solar.asp

I'd agree that a line-side-tap should be done by a C10, but I'm not even actually sure if it's required under that language.

BTW are you saying that a C46 can't install micro-inverter cabling because it's AC?

My understanding from how I read insurance amnimity according to classification, C46 is to terminate to the nearest combiner or disconnect ( to the point of AC disconnect) either being microinverter or combiner/disconnect DC side. C10 is to terminate to ANY SERVICE panel.

C46 guidelines are for installation of solar water heating, photovoltaic panels, and anchoring systems only.

I have a insurance policy for solar and actually perform it myself, however I need to have a certified C-10, or NABCEP technician through out the installation to certify and guaranty the work so that the client can collect on the state rebate checks. That's how its done for the qualifications.

I worked for a Commercial solar firm last year as a consultant, and the subcontractor we had under bid the work being C46. The problem is that the rates, and the insurance for those rates are different between C46 and C10 classification. A C-46 solar contractor can hire low end labor PV installers for under $15 an hour with no electrical certification or experience, while electrical subs are certified by the state of california, competent and qualified for the work at $30~$40. Because of insurance, a C46 still has to bid a project to hire a competent certified C10 to handle any lugging and installation past the point of combiner/disconnect termination, and even then a C10 has to verify that lugging. We actually had to terminate a MSA contract with a C46 sub we had, then send out the bid package so that it qualified for the work at the rates that were allowable, for certified work, because of how the insurance policies are written.

Now here's the catch 22, if an incedents of liability does occur, the insurance coverage will not cover the contractor unless the certifiable installer for the job was used for tht particular scope. You really have to get down to reading the fine print in the insurance policy. If at any time the insurance finds the contractor at fault for not having competent certifiable work according to the correct scopes, then that contractor will be in some deep trouble.

Now if you read the language correctly read what I highlight. Here is constructon law for you.
A licensee classified in this section shall not undertake or perform building or construction trades, crafts, or skills, except when required to install a thermal or photovoltaic solar energy system.
This is very vague language. To simplify that for you, it means do not pass go, passed any point of disconnect. Reason being if there is a tie in location that piece of pre existing equipment being a switch gear or service box, is not defined as part of that solar energy system, That includes service panels, as a service panel is not the solar energy system.

All the big solar firms (I.E) Sunpower, Borrego, Chevron Energy solutions have a class B license with a coupled C46 for the umbrella of insurance coverage. Then the RFP and SOW are sent out for bid to a C10 contractor to perform the work. That way the umbrella of all scopes of work are covered under insurance policies and the work is certified under all scopes. That is how it is to be done, in order to protect against project liability. The prime contractor dictates the work based off the prime contract, and then the sub handles the installation, and all 3 policies between GC class B, C46, and C10 are all bound for an entire umbrella of coverage. As stupid as it sounds, that's the way it suppose to happen.

jaggedben

Re: Solar Shingles

Or course I can't see your insurance policy, but I think you are confusing employee certification requirements with electrical contracting requirements. In California a Certified Electrician and a Licensed Electrical Contractor are not the same thing. It's true that all electrical work is supposed to be performed by a Certified Electrician. (I believe, the way the law is written, this applies to all wiring connections. So I think your DC/AC distinction is still untrue and arbitrary there.) A C46 contractor must employ a Certified Electrician to do the electrical work for a solar PV system. But that electrician does NOT need to hold a C10 License, that is a totally different piece of paper issued by a different state agency under a different state department.

Your mention of needing to do any of this to receive state rebates is silly. The CSI program takes no role whatsoever in enforcing this stuff. They only look for the approved interconnection application, and the interconnection department in turn only looks for a signed-off building permit.

As far as line-side-taps and such, it is pretty much only AHJs who would actually enforce anything. It basically comes down to whether the additional electrical work is enough to require a second permit or additional permit fee. Most AHJs (if they're paying attention) won't issue a permit that includes a service upgrade or subpanel replacement unless the contractor is a C10. When my company was only a C46 we subcontracted service upgrades to a C10 holder for this reason. If you can't get the permits then your customer can't apply for net-metering and that's how this is enforced. ;-) FWIW, a line-side-tap may or may not trigger an additional permit requirement from an AHJ.

SolarPowered

Re: Solar Shingles

The rules on (CSI) rebates are clear. That the work for installation are to be handled by a certified installer of that trade, and NABCEP is preferred. Myself as a class B can't just do the install as I am not certified in C46 or C10 so I would need a minimum to bind to my policy of C10, or employ someone of NABCEP to meet those qualifications. I've been through this already in some counties. CSI does not enforce, it is the jurisdiction of the county that enforces those rules.

Anyway enough on the difference of opinion.

This topic was about shingles so we can go back to discussing overpriced solar shingles.

MikeSus

Re: Solar Shingles

Gotta say when I first saw the title it sounded like a painful problem.


After reading it, it turns out to be a solution looking for a problem.

MikeSus

Re: Solar Shingles

Cariboocoot wrote: »

Just a reminder: not everyone lives in California. And boy are they who don't glad of the fact.

Yes there are! (most of AZ for starters )