(...) Let’s get one thing out of the way right up front: The North American electric grid is not one bad day away from the kind of catastrophic failures we saw in India this week. I’ve heard a lot of people speculating on this, but the folks who know the grid say that, while such a huge blackout is theoretically possible, it is also extremely unlikely. As Clark Gellings, a fellow at the Electric Power Research Institute put it, “An engineer will never say never,” but you should definitely not assume anything resembling an imminent threat at that scale. Remember, the blackouts this week cut power to half of all Indian electricity customers. Even the 2003 blackout—the largest blackout in North America ever—only affected about 15% of Americans.

We don’t know yet what, exactly, caused the Indian blackouts, but there are several key differences between their grid and our grid. India’s electricity is only weakly tied to the people who use it, Gellings told me. Most of the power plants are in the far north. Most of the population is in the far south. The power lines linking the two are neither robust nor numerous. That’s not a problem we have in North America.

Likewise, India has considerably more demand for electricity than it has supply. Even on a good day, there’s not enough electricity for all the people who want it, said Jeff Dagle, an engineer with the Pacific Northwest National Laboratory’s Advanced Power and Energy Systems research group. “They’re pushing their system much harder, to its limits,” he said. “If they have a problem, there’s less cushion to absorb it. Our system has rules that prevent us from dipping into our electric reserves on a day-to-day basis. So we have reserve power for emergencies.”

None of this means the North American grid is a perfect, or even an ideal, system. The electric grids that exist today evolved, they weren’t designed by anybody. Every electric grid on Earth is flawed, but they’re all flawed in different ways. So we can talk about serious problems with the North American grid—but that doesn’t mean that you should be stocking up on home generators and canned peas in preparation for an India-like event. The scale is different, and the problems are different, too.