Solar shingles?

[gspren]

  At a Delaware outdoor expo last week I talked to a few roofing contractors since I know we need to get a new roof within a year or two. One had solar shingles that replace the regular shingles. He said about 40% higher cost but would recoup in a few years, about 30 year lifespan expected. Any knowledge on these?

[Southside]

Elon Musk had a Solar Roof out a few years ago, I don't think it went well, maybe someone else ran with it? 

[peakbagger]

To quote Monty Python "Run Away"

This is at least the third roofing company solar shingles to try where they attempt to integrate a panel into an asphalt shingle. The two prior attempts failed. The problem with a solar shingle is there needs to be lot of electrical connections hidden away somewhere as each panel segment is quite small like 10 or 20 watts compared to conventional panel that is now going on 400 watts. So two connections somewhat accessible per panel compared to 40 smaller connections per panel hidden somewhere to worry about. The Tesla Roof is on its third major configuration and although they are tight on technical details the design is really a molded plastic underroof covered with snap in "glass" panels. Those panels are also very small so there is "gutter" system molded into the plastic to run all the small wires. They gave up making it waterproof and now strip the roof and put a waterproof layer similar to ice and water shield underneath. It a very expensive and good luck if it has issues 10 years down the road as Tesla is infamous for abandoning old technology. Plastic and hot roofs do not play well together and my guess is give it 10 or 15 year and widn event will peel then glass panels off and distribute them on the front yard and Tesla will not do squat. They mostly use the solar roof to get folks talking to them and then downsell them to their conventional panels. 

 I have no idea how those firms comply with the Rapid Shut Down standard that applies to all roofs on occupied spaces. 

IMHO, if you doing a new roof, get it stripped, put Grace ice and water shield bottom to top and pay the roofer to install proper flash in roof brackets to match up with standard racking. Then install standard panels and buy a few spares and stash them in a safe place. Ideally install the solar on non occupied roof like a garage and skip rapid shutdown and go with central inverter instead of microinverters or optimizers.  And install a good whole house surge supressor with low clamp voltage on the main panel and one on the PV circuit. Whatever you do dont lease or get creative with financing. There is book you should read call Solar Power Your Home for Dummies which will get you up to speed. 

[Joe Hillmann]

Did you get an actual price?  Or did the contractor just say it is 40% higher?

A few years ago elon musk's company said their solar shingles were the same price as a normal roof.  But it turns out he meant the solar shingles were about the same cost as material and insulation of the most expensive tile roof.  The installation was on top of that..

Compaired to a normal shingle roof they were 5 to 8 times as expensive.  Yet all the news stories at the time kept saying they were the same price as a normal roof.

[Joe Hillmann]

Also.  A roof isn't an ideal place to mount solar panels in most cases.

The roof most likely isnt at the proper angle for best power production.  

And if you live in an area with snow do you plan to keep the panels clear in the winter or just let snow build up and accept the panels will produce less or no power?

If I were looking into it I would have some questions for the dealer:

How do you access wiring with solar shingles?

Do solar shingles dissipate heat as well as solar panels on a rack?

Can you replace a single damaged one?

Then I would want to talk to someone they already did a roof for.  My guess would be that the installed system didnt do nearly what was promised and cost more than estimated.

[gspren]

  It's one of those things that sounds good in theory but not really practical yet, I say yet because it may be common someday, but not today. At my age and current financial state I will probably just get good shingle roof put on and not fool with solar although my back ground in research says it will be common "someday".

[peakbagger]

 I have built and installed 4 solar systems up in Northern NH plus responsible for the design of a couple of others. Solar panels are typically installed on roofs parallel to the roof line as long as they are not shaded and are facing predominantly south (Note east west can work albeit with lower output. There is free program called PV Watts on the web that is easy to use and will estimate output for a particular location. If anything its bit conservative. Yes snow can be an issue, there are some tricks to minimize the impact but the reality is that most PV production is in the Spring Summer and Fall. If there is access from the ground, a roof rake can quickly clean off panels. 

The key thing with solar is if your utility is solar friendly. Many states enourage solar and make sure the rate tariffs support it, other states do not and utilities can make export to the grid difficult. Off grid solar is a different story, more money up front and hard to justify economically.