New PV project
The Beechwood project (renovation and 2nd storey addition) will incorporate a solar array. Permits for the project are delayed because the City required more information on attachment of the array and the structure’s ability to accommodate it. In a fortunate coincidence, the Solar Canada 2013 conference and trade show is on right now, and we were able to attend and see first hand various PV and solar thermal technologies, racking systems, and the latest industry trends.
The Beechwood project will have both a sloped metal roof and a flat roof. Racking systems for metal roofs generally consist of an aluminum extrusion that bolts through the roofing with a neoprene gasket or sealant to create a water tight seal. The rack is then bolted to the extrusion. Most manufacturers make distinct mounting blocks to match specific roof profiles. For standing seam metal roofs, the rack mounts are clamped directly to the standing seam, which eliminates roof penetrations entirely.
This standing seam profile is typically reserved for commercial roofing applications but can also be used for residential projects (colours are limited though)
For the flat roof, the preferred racking system would be ballasted to avoid roof penetrations. Kinetic Solar has an interesting system that incorporates a flexible wind baffle. The baffle reduces ballasting requirements by directing wind over the panels and reducing uplift. The flexible baffle seemed like an improvement over fixed baffles because it was spaced away from the panels, allowing air to circulate around them to keep them cool and allowing easy access for maintenance. When the wind blows strongly enough, the flexible baffle bends forward obstructing the back of the panel to reduce uplift.
The wind baffle can be seen here, it looks like heavy gauge bent metal window flashing
Other noteworthy items:
- MicroFIT Program Update – For PV arrays under 10kW, the MicroFIT contract currently pays $0.396/kWh. Domestic-contect rules are still in effect, although this will likely change in the near future because of a recent WTO ruling.
- Solar car ports with integral electric vehicle charging stations (1st image in gallery below).
- Architectural BIPV panels (2nd image in gallery below).
- Vacuum insulated solar thermal tubes by Viessman (3rd image in gallery below).
