Artfully using stained glass to capture solar energy

A collection of eye-catching stained glass installations by a Toronto artist is generating solar power in three provinces, and one of them is in the process of being hooked up to the Saskatchewan grid.

"Lux Gloria" by Sarah Hall, at the Cathedral of the Holy Family in Saskatoon, is currently being connected to Saskatoon Light & Power's electrical distribution network, confirmed Jim Nakoneshny, facilities manager at the cathedral.

The artwork, which consists of solar panels embedded in brightly coloured, hand-painted art glass, had just been reinstalled and upgraded after breaking and falling into the church last year.

Once it is connected, the cathedral will be able to use the solar power produced by the art installation to offset its own power consumption from the regular grid, Nakoneshny added.

'When you use art, you build a story into it that makes people notice in a way that they don't if it's just technology.' —Sarah Hall, artist

According to Kevin Hudson, manager of metering and sustainable electricity for Saskatoon Light & Power, the solar panels are expected to produce about 2,500 kilowatt hours annually or about a third to a quarter of the 8,000 to 10,000 kilowatt hours consumed by a typical home in Saskatoon each year.

Nakoneshny expects all of this solar power to be used by the cathedral itself, although he said it's possible, if unlikely, that there will be times when the church system feeds power back into the grid. But that's not the point.

"This is, first and foremost, an art glass installation," Nakoneshny said. "The solar component is included to showcase many of the energy saving design elements throughout the building and show that a technical system doesn't need to be ugly."

In fact, the installation will become Saskatchewan's first building-integrated photovoltaic system (BIPV), where solar panels are embedded directly into walls, windows or other parts of a building's main structure. It's a trend that is expected to grow in the future as the traditional practice of mounting solar panels on rooftops isn't practical for many city buildings, including some churches.

Hudson said that, as far as he knows, "Lux Gloria" contains the first cathedral windows in the world to integrate solar energy collection into their stained glass.

Hall suggested it's a good way to raise awareness about green energy.

"When you use art, you build a story into it that makes people notice it in a way that they don't if it's just technology," the artist said in a phone interview.

"Lux Gloria" is one of four solar-stained glass window installations across Canada, along with two in the U.S., that Hall has created since 2005, and the first to be hooked up to the grid.

Some of those that are not hooked up to the grid still produce power for use within their own buildings. For example, Hall's "Waterglass" installation in Toronto produces 1,450 kilowatt hours annually, which are all consumed within Harbourfront Centre, the complex that houses it.

Colleagues uninterested in using solar cells

Hall had been working in Germany about a decade ago when an engineer named Christof Erban visited a studio she shared with several other artists to demonstrate a technique he had developed for placing solar cells between two layers of glass.

Erban asked if any of the artists would be interested in incorporating solar cells into their work.

"Everyone else in the room said, 'No thanks — too complicated,'" Hall recalled.  "However, I was immediately interested."

Hall, Erban and a glass studio in Germany worked together for about two years to refine the technique for use with art glass.

Hall first demonstrated the technique in "O Canada," installed in windows of the Canadian solar house designed by students at two Montreal universities for the Solar Decathlon in Washington, D.C. in 2005. The project was funded by Natural Resources Canada and the Chalmers Foundation, and the house is now part of the campus of Concordia University in Montreal.

Her other installations include:

• "Leaves of Light" at York University in Toronto.
• "True North/Lux Nova" at Regent College, University of British Columbia in Vancouver.
• "Waterglass" at the Enwave Theatre, Harbourfront Centre, Toronto.
• "The Science of Light" at Grass Valley Elementary School in Camas, Wash.

Each one incorporates solar cells of different colours — for example, silver in the cathedral in Saskatoon, blue at Regent College and gold at Grass Valley Elementary School — intended to match with the accompanying artwork and the façade of the building.

All those colours are commercially available, but need to be adapted for the artwork.

In the case of the Cathedral of the Holy Family, each solar panel was a different size and was trapezoidal in shape, Hall said. As a result, "all the solar work had to be hand soldered."

Because the solar cells aren't transparent, Hall adds a high-tech "dichroic" glass to the back of the cells in some cases to make them colourful and reflective.

"Waterglass" also incorporates heat-mirror glass in order to reduce heat leakage into and out of the building.

New solar technologies for windows that would allow them to be transparent and generate solar energy, such as spray-on photovoltaic coatings, are currently under development for use in building-integrated photovoltaics.

Hall said she is very interested in those more advanced technologies for her future projects.

"It certainly is exciting and we're certainly watching to see how it goes."