Thanks to decreasing costs and accessible grant programs, the number of Albertans with home solar panels has grown exponentially. While some people are content just getting a break on their energy bills, many look at rooftop solar systems and envision pumping electricity back into the province’s power grid — and generating extra cash in the process.
“It's one of the more common questions that we receive, especially among a certain audience that maybe have a really ideal rooftop, and they have the funds or have access to the funds to support a larger system,” says Greg Sauer, vice-president of business development for SkyFire Energy.
The question often comes up in the beginning stages of conversations with new customers, Sauer said: Is it possible to max out my home and become a net supplier of electricity?
The first hurdle in plans to become a small-scale power plant is regulatory. Under Alberta’s micro-generation regulations, home electricity production is only intended to offset your own annual energy consumption.
Sauer said the limits set out in regulations are a bit unclear, but generally this means having enough solar to produce around 105 per cent of your annual electricity needs.
“Because not every year is going to be the same in production and solar systems over time decline, there's a little bit of a margin or a tolerance,” he said.
But why stop there if you have the space to generate twice what you normally consume?
Over-sizing is attractive to customers because the more solar you install, the lower the price of each installed watt. Some people also imagine that when the system is paid off, then there is an opportunity to generate revenue, Sauer said.
Which brings us to the second, and more serious challenge. Our electrical infrastructure wasn’t really designed to accommodate solar panels on every roof sending power back into the grid.
“Micro-generation users connect to the grid via the distribution system provider in territory where the generator is located. There are technical limitations to the amount of power that can be imported on those distribution system lines, generally and specific to the actual location,” says Geoff Scotton, a communications advisor with the Alberta Utility Commission, which administers the provincial policy set out by the government.
“Generally speaking, those distribution systems were designed and built to distribute and deliver power, rather than collect it.”
That said, the grid does have some collection capacity and people can seek and obtain agreements with the distribution system operator, Scotton added. “This is for both safety and capacity reasons.”
“Even the way we're designing communities today, the servicing they're putting in really hasn't changed from what it was in the 90s and the 2000s,” Sauer said.
If a neighbourhood or a street is serviced by a 100 kVA transformer, that is the limiting factor. Within those capacity limits, the issue becomes one of fairness and equity.
“You could have 10 10-kilowatt systems connected that transformer. Or you could have 25-kilowatt systems connected to that transformer. At the end of the day, it's the same,” Sauer said.
“From my perspective, personally, I'd like to see more people have the ability to connect and offset their consumption than one or two or three people have the ability to put two or three times the size of system on and take up that capacity.”
