CHARBONNEAU – One big grid would solve our future electricity needs

WE FACE TWO PROBLEMS that a Trans Canada electrical grid would solve.

Renewable sources face a storage problem. When the wind blows and the sun shines, turbines and solar cells produce power. If not used immediately, that power must be stored in batteries, or some other means.

Also, Canada will need to triple the electrical capacity of our existing fragmented grid to meet the future needs of electric vehicles and heat pumps.

The storage problem could be solved by the sheer size of a Trans Canada grid.

Canada’s electricity generation capacity is about 149 GW. That’s a big reservoir. However, that capacity is fragmented; it consists of a number of jurisdictions that are not connected by any major transmission lines.

If a grid is large enough, wind and solar power can be dumped into the grid at any time. The grid replaces the need for storage.

It works like this:

Imagine that a power grid is a reservoir of water with customers drawing from the reservoir and generators pouring water into it. The goal of the operator is to keep the supply and demand constant. That way the reservoir level is maintained.

The level of water in the reservoir corresponds to the voltage in a power grid. If you pour too much power into the grid, as wind and solar sources could in a small grid, the voltage could suddenly rise and potentially damage equipment plugged into the grid.

If customers drain more power out of the system than the operator can pour into it, the water (voltage) drops perilously and customers must turn off the taps (pull the plugs).

That’s what happened to Alberta in January.

For days, the grid operator asked Albertans to conserve electricity as the grid struggled during a brutal cold snap. The provincial government took the unprecedented step of triggering the emergency alert system, and Albertans’ cell phones and televisions blared warnings to residents telling them to limit electricity use immediately.

But if Alberta was to draw from a much larger reservoir, that wouldn’t have happened. With thousands of generators pouring electricity into the reservoir, the calamity could have been averted.

Alberta’s grid capacity is around 16,000 MW, which is relatively small. If Alberta was part of a Trans Canada electricity grid, the voltage would be smoothed out.

And a shared Trans Canada grid would mean that no one jurisdiction would need to triple its capacity.

The rolling demands of Canada’s electricity needs mean that not everyone needs power at once. Peak demands typically occur twice a day: in the morning when Canadians get up and turn on the toaster and make coffee, and in the evening when supper is made.

The rolling demands mean the strain on the grid is reduced. Of course, there will be seasonal demands on top of daily ones but operators can anticipate those. And the weather is rarely cold on both ends of the continent due to oscillations of the jet stream.

A Trans Canada grid will be expensive to build but, more than the cost, it will take political will. With the hurdles that the Trans Mountain pipeline faced in being built, it’s achievable.

David Charbonneau is a retired TRU electronics instructor who hosts a blog at http://www.eyeviewkamloops.wordpress.com.