Installing Solar Panels On A Tile Roof Can Be Tricky [Video]

This is my 1st video interview with John Shaw Project Engineer Bella Energy of out of Louisville Colorado. Anderson Hoke Project Engineer is also interviewed in this clip.

SolarDave: Installing solar panels on a tile roof can be tricky, what is your approach ?

John Shaw: The easiest way to do PV on a tile roof weather that is curved Spanish tile or flat concrete tiles is to use building integrated PV product. Sharp has a product, Open Energy has a product, both of them basically hang on the battens. They are silicon cells so they are not the thin film amorphous that simply means that they are as efficient as a standard panel from Sharp or Evergreen or what not.

They get screwed in to the roof decking just like the concrete tiles. They integrate with the concrete tile with a lip, this particular one made by Open Energy is a 35 watt tile, it replaces 3 concrete tiles and it is basically the same height as a concrete tile and the width of them is the same and it is really the easiest way to do solar on a curved Spanish tile or flat concrete tile roof.

If one wants to do standard tiles, there is a couple of ways to do it - the most laborious way would be to remove all the tile and and fasten to the beam.

But the way Sharp suggests that we do it is basically retrofitting so we back out just the tiles necessary where we need to make our attachments.

Anderson Hoke: You can pull one or two or 4 tiles right where you need to make the connection. You can pull out just a few tiles but at that point you can either install a standoff you want a longer one than this and flash around it, the tile institute would like to see flashing at the level of the under lament. That is interwoven with the lament and another flashing at the tiles - double flashed, that is the way any type of pipe is supposed to be flashed coming from tile but actually the way Sharp suggested you do it one of the leading manufacturers of PV is to drill a hole in the tile and they have a product fits through the roof - drill a hole in the tile and put the tile back down over their product and they have a combination of chalking and butyl tape method they use to seal the hole. And you can mount your PV on top of that, some really don’t like that method but that is what Sharp is recommending.

John Shaw: Specific to that type of installation so basically retrofitting over a tile roof is that it is rather laborious in Colorado where we have to deal with 90 to 136 MPH winds so we typically need more attachments than other parts of the country.

For a 4 kilowatt system that might cover 350 sq ft we might have 36 attachments so that means 36 different points on the roof where we need to remove one to 4 tiles locate the rafter drill the tile replace the tile chalk butyl etc, long story short Sharp tells us that in at least in California we need to be collecting about $2 more per watt and considering that the price in Colorado for standard efficiency panels is about $7.50 a watt all inclusive including tax, you are looking at increasing it from $7.50 to $9.50 and that is more than 20%.

More pictures of tile roof solar install.