Sudbury farmer harnesses (partial) power during solar eclipse

An organic produce farmer in Sudbury, Ont., used his solar power generating station to measure energy before, during and after the partial solar eclipse on Monday.

Stuart McCall's solar-powered farm saw a 74 per cent drop in energy when moon moved in front of sun

Stuart McCall has solar panels at his farm in Garson, Ont. He measured a 74 per cent drop in power Monday, when the moon went in front of the sun during the solar eclipse. (Jason Turnbull/CBC)

During the rare solar eclipse on Monday, Stuart McCall wasn't staring at the sun like the rest of the country, he was looking at a power inverter.

The organic farmer has a solar-power generating station at his farm in Garson, Ont. The panels are installed on the roof of his house.

Some of the power is used to operate the farm, while the rest is sold to Hydro One networks.

McCall says he typically looks at the power inverter several times throughout the day to see his power production level.

He admits he's always been fascinated with climate science and the effects that sunlight, humidity and rainfall have on farming.

On Monday he decided to record those measurements to determine the changes a solar eclipse might cause.

"I thought, here's an opportunity. It may not come around for many, many years in the future, but certainly it's great opportunity to record what you're seeing during an event like this."

The maximum power for McCall's system is 10 killowatts or 10,000 watts.
Stuart McCall (Yvon Theriault/Radio-Canada)

According to his measurements, at 9:30 a.m. the power usage showed 8,750 watts. At 2:50 p.m. — just after peak eclipse time — the power usage measured 2,250 watts.

That is a 74 per cent drop in solar intensity, during the time when the moon went in front of the sun.

75 per cent partial eclipse predicted

"It's kind of in line, I think, with what was predicted, like about a 75 per cent partial eclipse here," says McCall. "So the calculations kind of drive with what was predicted."

Unlike the total solar eclipse in the United States, Canadians only experienced a partial eclipse.

McCall says he also took measurements at 3:20 p.m. By then the farm was back to 5,500 watts, double what it was during the eclipse.

There are temperature and humidity sensors at the property too.

McCall measured a seven degree drop in temperature during the eclipse. The thermometer showed 29 degrees Celsius before the eclipse, and 22 degrees Celsius during the eclipse.

The humidity at the property changed from 90 per cent before the solar event, and 77 per cent during the eclipse.

Changes did not affect produce on farm

None of these changes affected the produce McCall grows on his farm.

"It was just interesting … I'd love to graph this some time."

The initial cost to install the power generating system on the farm in 2015 was $41,000.

McCall says the venture has lived up to his expectations, since he sees about $6,500 yearly for sending power back to the grid.

"[The solar power station] reduces our environmental footprint on the farm, as far as climate goes. And we're providing a service to the general public, which is also really good."

With files from Robin De Angelis