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For those that want to and have to use solar panels, this seems like it would be a major advancement. The panels themselves replace the shingles: no glass cover, no frame, no mounting. That is what the literature says. Has anyone had experience using these panels?
Ref: Mother Earth News Feb/Mar 2002 pg 72
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Are you talking about PV Shingles, such as http://www.ovonic.com/unitedsolar/roofingsystemshingle.html ?
These are designed to look and apply just like 3-tab asphalt shingles. I've never used them but... have plenty of concerns:
The basic rigid panel on brackets above the roof is a lot easier to set up, and have a nice watertight box with regular 1/2" KO's to connect conduit into. However, these tend to look ugly and you end up having to pay for regular roofing and PV panel over same area.
I'm partial to standing seam panels that would integrate into a metal roof. See attachment or
http://www.ovonic.com/unitedsolar/roofingsystemarchitech.html
I think these combine the advantages of the other two... serves as the roof material itself, saving on roofing costs, yet are in larger modules to reduce the number of wires and provide real junction boxes.
Just my 2 watts.
*Hi Jim,Doesn't seem like many people use the PV shingles or the standing seem panels. Do you understand why? Is there any location where you can get cost information on solar shingles/standing seam panels verses a wind generator? The wind speed at the building lot is not great, but it seems fairly consistent.Have seen several wind generator in catalogs that look very good. I get worried when something like a wind generators, which has constant use, bearings wear out. Should this be a concern?thanks
*Ken:With the last name of "Ballard" I'm surprised you aren't big on fuel cells :). Why low usage?:Photovoltaic economics just do not work yet when you are near the grid. If you have consistent wind, AND can build/maintain the tower/electrical yourself, wind power would be VERY economical (same with micro-hydro = almost free). IF not DIY, there is not enough service infrastructure yet for wind or micro-hydro to be cost effective (e.g. those who can service it will charge you thru the teeth, same with ready-to-go equipment in catalogs).
*Ken -I'm completely guessing, but... the PV shingles are based on flexible solar cells, so the price is higher than rigid panels. Standing seem panels of course work with metal roofs, which at least around here aren't at all common. And based on even more non-data, my impression is that most PV installs are retrofits to existing (asphalt shingled) houses, rather than integrated at the design phase. I've seen pictures from Europe where they not only integrate the PV but make it a feature, such as a restaurant/cafe that had basically a glass roof with the cells spaced out every few inches, so that they cast interesting shadows that moved around inside as the sun progressed across the sky. Form & function unite.On the generator bearings, that would be almost a non-issue... good bearings last a very long time. Think of all the industrial motors that keep running 24 hours/day (air handlers, factories, etc). You can lower the tower back down to get to the generator for repairs when they are eventually needed.Keep in mind that PV is more expensive but will work on almost any site, as long as there aren't big shadows, and is easy to design based just on your latitude. Wind is cheaper but VERY site specific; your site and the neighbors might not be the same. You really need to gather some hard data as to what type of wind speeds to expect during all 4 seasons, keeping in mind there is more wind at the top of the tower then on the ground. And of course check if zoning even allows towers.I'm quickly getting out of my league, but if you haven't already seen it, check out Home Power (http://www.homepower.com). You can get some good stuff off the web, or get their CD set of past articles and all kinds of spread sheets and guides to help design systems (and of course subscribe to the magazine). And might look for Steve Strong's book: "The Solar Electric House". For wind energy, look for the book "Wind Energy Basics" by Paul Gipe. There is also the American Wind Association at http://www.awea.org although I've never dealt with them.A few more resources are attached (PDF file).
*Art,Wish I was related! Thanks for the practical advice. By implying low usage, I meant that a search did not reveal any discussions which translates into low usage.JimThe lower cost of wind generated power sounds great. All I need to do is convince the neighbors they are not hearing any hum and make sure the County doesn't go into shock if you erect a tower. Since this alternate energy thing is growing in importance daily, it probably should be covered in FHB. [Hint, Hint: Andy]
*This organization organized a tour last summer of three installations in Madison, WI. One was PV slate, one PV "three tab", and one PV on standing seam.Very practical data available from these installations. If you are serious about it they may be able to give you some contacts that can tell you how it's working (or not working). I was looking to do PV applied to copper standing seam when I took the tour(and still may) but field application was not recommended.Good luck!Wisconsin Green Building Alliance c/o Connie Lindholm, Director759 N. Milwaukee Street, Suite 304, Milwaukee, WI 53202Phone (414) 224-9422 E-mail [email protected]
*Ken,I'm with Art in that the economics are just not competitive yet. We started building our own home 2 years ago and took a hard look at a combined PV / wind system. We built about 500' from nearest pole that elec. would place for us and it wasn't even a close comparison here in W. NY ($0.134/kWh). Also, in addition to steady wind, it really needs to be pretty strong to make much electricity.In my opinion, the other big limitation is lifestyle. To maintain our fairly average American lifestyle, we'd need to invest about $25 k in hardware alone. Tough to sate our hungry appetites with PV and wind.