Looking for feedback from homeowners of solar panels on roofs

[russ]

I don't see it this way, but ok. Loosing one unit only effects 10W of power. The rest is OK. Each styleTILE has it's own bypass diode.

The connections are maybe a bit frightening but with basic understanding of electricity there shouldn't be any problems.

Baloney - I am referring to the electrical connections being problematic. Forget your "basic understanding of electricity" - loose connections, poor connections and corroded are always a concern.

This is like Dow's shingles - dead horse.

[sumoborac]

I am really interested in the questions raised here. I doubt, though, that we will hear back from the OP and get conclusive answers.
Whenever I talk to friends and acquaintances about the benefits of solar PV, they will often say: "But aren't there now these shingles available?" Everyone has heard something about these shingles (I suppose mostly they are referring to the Dow Powerhouse shingles). Nobody, however, knows anything specific. Ever. Other than a perceived aesthetic improvement, I cannot see any (and I mean: ANY) benefit over traditional panels.
I checked out the Dow Powerhouse website, and it is a letdown. Lots of happy colorful messages about savings but no hard data and no specific info on their system's setup.

I'm here. Bit late, but not my fault I didn't received any "replay to thread" email until tonight.
But I do see some benefits over the traditional panels.
1. It is a roof tile. So no need for having a roof so you can put the panels on.
2. Much better roof coverage. When you put the panels on the roof, usually there is some "extra" space around them, because there are limitations with the size of the modules. At least here in Slovenia. Like this - http://rwthomeremodeling.com/wp-cont...olar-panel.jpg
This is a standard view.
3. The looks. The "extra" space around it makes the solar panels usually sticking out. So an aesthetic improvement.
4. Repairs. In our climate we get at least 5x a year the icy hail - http://upload.wikimedia.org/wikipedi...Hailstones.jpg
Those DO break car glass. At least here. And the cost of replacing 3 or 5 250W module against 3 or 5 tiles - big difference. The cost is quite lower. I know that most PV roofs are insured, so the cost is on the insurance company, but still.

But thanks for the comment. I will update the project and page with FAQ and more detailed info about styleTILE.

It seems that it's all the rage these days to "do something with solar." Even my former HVAC contractor is now "thinking about it." I wonder what world-renowned "innovation" he will provide soon. Perhaps yet another sensational rendition of the PV roof shingle/tile?

Maybe this days it is. But the styleTILE start is about 5 years ago when most people didn't knew what solar module even is.

[sumoborac]

Baloney - I am referring to the electrical connections being problematic. Forget your "basic understanding of electricity" - loose connections, poor connections and corroded are always a concern.

This is like Dow's shingles - dead horse.

Ok, misunderstanding on my end. We designed a custom connector for this project. It deals with all 3 problems: There is only one way to connect two styleTILEs together. So no "lose connections". Not connected or connected. The poor connections are solved with the shape of the connector, so it works like a spring in a way. So there is always a good connection. Corroded - the connectors are made from bras coated with "Ni" - nickel. So far, the tests didn't showed any corrosion.

But to be fair... this is something new. So there are possibilities that not everything is done perfect the first time. But this is how evolution works.
And this is one of the goals of Indiegogo campaign. To test this things. So I can give a full answer, backed with paper.

I would love to show you the connector but currently there is no patent shield for it, so I'll shot a picture of it next week when I'm back in the office and I'll post it.

[sumoborac]

The OP's website painted a story of how his father objected to having to put a brand new roof in (their roof was too old and should be replaced before solar) only to have the solar people drill holes in his brand new roof. I kinda chuckled and asked myself "What's the big deal? People drill holes all over brand new roofs for vent pipes anyway. Won't you have to drill holes for vent pipes with the solar tiles, too?" LOL

Ok, it might not be a big deal for you, but for my father it was the deciding point. And after 5 years I and new roof facing north, I found that he was right. When you make a hole in roof, there is a hole. With proper work, it can be sealed quite good. But never as good as before no-hole situation. The experience was with the chimney hole. They created a little bigger hole for the chimney and they had to seal the whole section higher from the chimney. Maybe I can't explain it good enough

In the OP's first post, he said "the idea is to eliminate huge and not very beautiful solar panels of roofs of residential houses". I think this vision is flawed. I bet you not too many people think the current solar panels are ugly. People (myself included) may prefer to have the same roof style as the rest of the subdivision, and just put solar panels on top as needed. After all, the market to install new solar on top of existing roofs is vastly bigger than the market to install customized solar tiles on brand new homes.

Maybe I've expressed myself wrong. The styleTILE is a great thing when you get in situation like ours was. Old roof need of replacement. Why not do it in one step with styleTILE?
It would be stupid to remove a perfectly good roof to put on styleTILE. Agreed. But looking around I see many roofs being replaced. It goes in waves, since no roof tile is forever.
And it is a great thing when you are building a new house and you wish to have solar energy.
Yes, the market for styleTILE is smaller as installation on the roofs, but it exists. I don't want the global dominance :P

The focus of the vision should not be about the aesthetic just because the OP thinks the current solar panels are big and ugly (too subjective to be agreed by everyone). The focus should be about the economics of the savings when combining tiling and solar together into 1 piece. Show people the money (savings) and they'll follow.

Ok, I'll bite. With automated production I can get quite close to the price of normal solar panels. So the end costs of new roof+standard modules are the same as styleTILE roof. And to be honest, sometimes it feels like comparing Ford to Ferrari. Not everyone looks at the solar energy only from the economics point. Otherwise we would all drive the same cars, wouldn't we?

[sumoborac]

The number of connections that would be next to impossible to access scare me as much as anything.

The access is not problematic. After the new-year I'll try to make a short video about replacing the tile. All you need is 3 wood wages (like this - http://www.hastiles.com/images/plugsmain.png), a small metal saw, pliers and a replacement tile. And about 10 minutes (ok, 30 if you do it for the first time).

[sumoborac]

Sorry to go off topic but these shingles after reviewing the site.. The contacts look a bit sketchy. No way to guarantee the friction/pressure fit will last through thermal expansion and contraction.

Why not? We solved the problem with two solutions - the expansion and contraction is solved on every tile. The male connector can move for 5mm in the row way. The friction/pressure is solved with the design of the connectors so they work like a spring.

Yes, I know, I can't know what will happen in 30 years, but thats why I'm trying on to raise money. So I can test every aspect of the styleTILE on the long run. So I can have a paper for each of the "new solutions" to back me up.

[SunEagle]

The integrity is quite perfect. The shape of the module is not something new. It is used for more then 150 years. Usually the tiles are from concrete - http://www.podarimo.si/slike/slika31344771806cpg.jpg
So the rain and moisture aspects are quite covered.

OK. I understand how a tile roof works but here in the US there is a layer beneath the tiles that keeps out the rain. The picture of you installing your tiles on a wooden stringers looked like there was a big opening below.

Is there another layer of roofing material below the wooden stringers that keeps out the rain? If not then how are the tiles sealed to keep out water?

[Volusiano]

Ok, it might not be a big deal for you, but for my father it was the deciding point. And after 5 years I and new roof facing north, I found that he was right. When you make a hole in roof, there is a hole. With proper work, it can be sealed quite good. But never as good as before no-hole situation. The experience was with the chimney hole. They created a little bigger hole for the chimney and they had to seal the whole section higher from the chimney. Maybe I can't explain it good enough

You talked around the subject but never addressed my question: where do you put vent pipes when you install the styleTile if you don't cut holes in the roof to feed the vent pipes? Especially if your scenario is to replace and existing roof with styleTile -> an existing roof already has many vent pipes.

Maybe I've expressed myself wrong. The styleTILE is a great thing when you get in situation like ours was. Old roof need of replacement. Why not do it in one step with styleTILE?
It would be stupid to remove a perfectly good roof to put on styleTILE. Agreed. But looking around I see many roofs being replaced. It goes in waves, since no roof tile is forever.

Maybe for shingles roofing your styleTile can replace the shingles. But a lot of homes use concrete or clay tiles that can easily last for 50 years. The only part that needs replacement is the underlayment, which should last around 15-20 years. Your styleTile would not apply for concrete or clay tile roofs because you don't replace the tiles, only the underlayment. So your market gets narrower than originally claimed.

[sumoborac]

Ok, thanks for the response. I am interested in your roof tile but I am not quite sure I understand completely. These bypass diodes are also part of my traditional panels. Nontheless, when partial shading occurs, that string will suffer quite a bit in terms of output despite the new power point tracking of my SMA inverter.

In traditional panels the baypass diodes are usually in the box on the back of the panel. So when shading occurs, it bypasses the whole vertical line in the module. So let's say you have a 24x8 cells on the module. The bypass is usually done on every 2 vertical rows, so if you have a shaded cell, the bypass will be 16 cells. Some of the modules have a bypass on every line but I haven't seen those much. If you have a shade over a horizontal row, the module won't work (or better, it will be bypassed fully).

Can you provide the number of kWs installed on that roof? Do you use a string inverter? How much in actual AC power does this system put out on a sunny day?
What kind of voltage do the connected tiles put out on a cold sunny day? I believe that a single cell has a certain nameplate rating but I am really curiouos about ACTUAL performance in the field. Do you have any data on this?

Sure. Currently I have 8 strings on the roof. The roof has two versions of styleTILE (the 9W modules, old cells and 10W modules, new cells), so 4 string of 350 modules and 4 string of 340 modules (the new cells have higher voltage output, so I had to lower the number to be safe because the Uoc can't exceed 1000V). So around 26kW. I use SamilPower SolarLake inverters 3x15kW (http://samilpower.com/product_detail.php?product_id=9) because I'll probably add another 3-4 strings on spring. I choose the SamilPower because in our country there are some non-standard request for reactive power (by some specific formula), and they created a custom firmware for us. There are only two other inverters that I know of that are allowed in our grid-tie PV arrays.
The normal output on a sunny day is around 105kWh produced. But bear in mind, that the roof isn't optimally positioned (we are facing south-south-east) so I lose about 2-3 hours of sun every day. The roof is on 15° angle. I managed to produce little over 3GWh in one month in the summer (I wish everyday would be a summer. Today the production was like 7kWh total. Fog the whole day :/ )

What do you make of this data? Good? Bad? Missed something?

I wish I could give you some certified data about all this, but every certified data costs just to much for me at the moment.

[sumoborac]

You talked around the subject but never addressed my question: where do you put vent pipes when you install the styleTile if you don't cut holes in the roof to feed the vent pipes? Especially if your scenario is to replace and existing roof with styleTile -> an existing roof already has many vent pipes.

Am... vent pipes? I honestly don't know what would that refer to on PV roof. I thoutght you are talking about water panels (for hot water)
There is no need for any holes in the styleTILE roof. From the end of the string to the inverter there is a shielded cable which is under the roof.

Or am I missing something?

Maybe for shingles roofing your styleTile can replace the shingles. But a lot of homes use concrete or clay tiles that can easily last for 50 years. The only part that needs replacement is the underlayment, which should last around 15-20 years. Your styleTile would not apply for concrete or clay tile roofs because you don't replace the tiles, only the underlayment. So your market gets narrower than originally claimed.

True. But usually when people replace the underlayment (the construction under the roof tiles?) they also change the roof tiles (at least here). And why not change the the tiles if you are planing to have the PV roof?

[sumoborac]

OK. I understand how a tile roof works but here in the US there is a layer beneath the tiles that keeps out the rain. The picture of you installing your tiles on a wooden stringers looked like there was a big opening below.

Is there another layer of roofing material below the wooden stringers that keeps out the rain? If not then how are the tiles sealed to keep out water?

Huh, interesting. Here the second layer is usually only the "steam" foil to let the steam and moisture from inside the house out,but not the other way around.
What is the point of having roof then? To have a shade?

The tiles are not sealed. They have around 8cm of double coverage, and they are at an angle, so the water drips down. To be clear, the styleTILE is not to be used on roofs with less then 15° angle. We had quite few rainy days this year, even with winds but no water bellow.

Well, something new learned

[sumoborac]

Ok. Replied to everyone. Enough for tonight

I'll be back tomorrow, If anyone has more specific questions you can also send me an email at gregor[at]pollak.si

Gregor Pollak

[bcroe]

Replys

Hi Guys! Don't know why, but I just received the first mail
"Replay to thread" today, so I didn't saw any of your comments until now. Gregor

Something is wrong. I have started receiving "Reply to thread"s from things I read a week
ago. Bruce Roe

[Volusiano]

Am... vent pipes? I honestly don't know what would that refer to on PV roof. I thoutght you are talking about water panels (for hot water)
There is no need for any holes in the styleTILE roof. From the end of the string to the inverter there is a shielded cable which is under the roof.

Or am I missing something?

Maybe home construction in Europe is different than in the US. What I'm talking about is the drain/sewage plumbing vent that allows air to be drawn in when water is drained from the bathroom sink/shower/tub/toilet. It's very common in the US to run this plumbing vent pipe directly up through the roof. There are other ways to avoid this, but usually it's common practice and the lowest cost to plumb bathrooms this way. Also, bathrooms in the US usually also has an exhaust fan that draws out moisture/odor from bathroom/toilet. This exhaust pipe usually is plumbed directly up through the roof as well. Similar with kitchen exhaust fans for cooking. Or ventilation for the laundry dryer (this can either go out to the side or up through the roof).

That is why it's no big deal at all in the US to have holes through the roof for these kinds of vent pipes. With proper flashing installed for these pipes, the roof should remain leak free with no problem at all. That's why the whole premise of your video about how your father objected to having holes in the roof doesn't resonate with me at all. Holes in the roof are no big deal in the US. Holes for solar panels with proper flashing should be no big deal just the same.

[Volusiano]

True. But usually when people replace the underlayment (the construction under the roof tiles?) they also change the roof tiles (at least here). And why not change the the tiles if you are planing to have the PV roof?

Shingles may need to be replaced more often, at the same time as the underlayment replacement. But if concrete or clay tiles can last 50 years, why pay extra to change them when you don't need to? What roofers do in the US is simply set aside the concrete/clay tiles nearby on the roof, replace the underlayment, and simply put the concrete/clay tiles back on top again.