Could solar power be used in Calgary?

By Sean Willett, September 29, 2015 —

While we don’t use them much in Alberta, there are ways to generate electricity other than coal and gas. One of these is solar power, which has yet to reach anywhere near the level of ubiquity of other green-energy sources. For many people, the reason for Alberta’s distaste for solar power seems obvious — there must not be enough sunlight.

This assumption sounds reasonable, as Alberta is thousands of miles north of the equator and experiences long, cold winters. But is it actually true? Using some simple math and publicly available information, it’s not too hard to figure out.

According to Natural Resources Canada, Calgary gets an average of five kilowatt hours (kWh) a day for every square metre, depending on the angle you’re measuring from. This is fairly high in comparison to many other areas that rely heavily on solar power. Germany, which is one of the world’s leading users of solar power, gets only about three kWh a day for every square metre.

Of these five kWh per square metre, we are only able to use what a solar cell is able to turn into usable electricity. The best solar cells currently available run at around 16 per cent efficiency, meaning that a top-notch solar panel in Calgary will generate about 0.8 kWh per square metre on an average day.

But is that enough to power a home? According to Alberta Energy, the average Calgarian residence uses about 20 kWh a day. This is a lot — an average household in Germany, by comparison, uses less than 10. With so much energy needed a day, a Calgarian house would require about 25 square metres of solar panelling to meet all of its electrical needs. This would look like a five by five metre square, a size that could easily fit on the roof of an average home in Calgary.

So could we make the switch to solar power? Probably, but the answer is more complicated than a few simple calculations. There are other factors — the cold could reduce the efficiency of the solar panels, many residences may be blocked off by the sun and, of course, solar panels aren’t free. But they would work — and work well — even in a place as seemingly desolate as Calgary.

The better question, then, is whether we should make the switch to solar power. Again, the answer is complicated. We would need to fundamentally change the way we treat electricity in Alberta — a tall order for a province that burns more coal than all of the other provinces combined. But with threats of climate change and resource scarcity staring us down the barrel, it may only be a matter of time before we start seeing more and more solar panels on Calgary’s roofs.

Sean Willett is a third-year natural sciences student. He writes a bimonthly column about environmental issues called Parks and Conservation.