Professor Michael D. Mehta of Thompson Rivers University makes a number of good points in his article regarding a secure electrical system (Armchairmayor.ca, March 6, 2021).
However, he’s thinking in the wrong direction when he suggests that the solution is microgrids.
The recent electrical blackouts in Texas have focused the problem of electricity security. In a state that prides itself on independence and abundance of energy, it was the height of irony that they should suffer from an electricity shortage that left people freezing in the dark.
Texas’ problem was that its electrical grid was too small. In an attempt to avoid federal regulation, Texas constructed a grid that is a virtual island. So when the cold snap hit, when wind turbines froze and natural gas generators quit, they had only themselves to rely on.
But not so for all of Texas. El Paso in eastern Texas did just fine, thank you. That’s because they were not connected to the Texas grid but rather to the much larger Western grid.
You see, there are three major electrical grids in North America: the Eastern Grid, the Western Grid and the Texas (ERCOT) Grid, El Paso picked a winner.
The big problem facing green energy is storage. Wind turbines and solar panels are great when the wind blows and the sun shines. But they usually produce too much power when we don’t need it and too little when we do. Storage seems like the answer.
However, as Professor Mehta mentions, no affordable storage system exists with the capacity needed. A number have been proposed; batteries, small-scale pumped hydro, compressed air, and flywheel technology.
Mehta suggests that the solution is not a bigger grid but smaller microgrids: “A microgrid is a local network of generators, often combined with energy storage.”
“Such systems can increase reliability and drive down carbon emissions when renewable energy is used,” says Mehta. “When combined with smart meters that reconcile inflows and outflows of electricity, microgrids provide real-time energy data. When a microgrid goes down, it only affects the local region and not an entire state or province.”
With one big continental grid, there is no storage problem and no one has to go without electricity.
One big grid solves the storage problem by virtue of its size.
The demands on one big grid are predictable. Cold snaps can be are forecast. In that case, thousands of generators, from big hydro dams to small run-of-river, solar and wind generators can be activated.
On an ordinary day, demands on one big grid are even more predictable. As people rise and shine on the Atlantic coast and turn on toasters, heaters, air conditioners in the summer, the demands on the West coast are minimal.
As the sun rises across the four and one-half time zones of our continent, the demand follows the sun. While the demands are not exactly constant they are predictable.
Of course, Canada doesn’t have a cross-country grid and neither does the U.S. Most of our connections are oriented in the worst way: they are North-South, in the same time zone where demands occur at the same time.
As Professor Mehta says, transmission lines are costly to build and lose power. The power loss can be minimized through use of High Voltage Direct Current transmission lines.
The construction of lines is a political problem, not one of cost. When the Trudeau government decided that the Trans Mountain Pipeline was in the national interest, he bought it and built it.