Cold Hard Truths


Who shall lay out those constraints, clearly, credibly?

Who shall lay out those constraints, clearly, credibly?

Fortnightly Magazine - May 2017

Once, electricity was the exclusive province of utilities and regulators, and their vendors and experts. The public’s limited understanding of electricity’s cold hard truths wasn’t problematic.

That all changed in the seventies. Since then, third parties have increasingly demanded and been granted a role in plotting electricity’s path. This trend accelerated in the nineties, with deregulation. And accelerated to warp speed in the last ten years, propelled by the push for a low-carbon future.

Millions of Americans have developed a real interest in electricity’s future. Particularly younger Americans, many of whom aspire to be activists and disruptors.

EES North America

No longer an exclusive province, the public’s limited understanding of electricity’s truths is now problematic. Notions that defy basic scientific and economic constraints too often catch on.

Who shall lay out those constraints, clearly, credibly? And what are the coldest hardest truths that a much more involved public must grasp? Here’s one, an especially cold and hard truth.

Electricity is instantaneous. It can be switched on, and off, in an instant. When the sun peeks through the clouds, solar panels make electricity that instant. And when the clouds drift back, the panels stop that instant.

But our lights, air conditioners, televisions, etc. are on for minutes or hours at a time. If the electricity supplying them varied like cloud cover, they’d erratically switch on and off.

So, what matters is not the maximum amount of electricity the panels can make. But how much electricity they do make over the course of a day, a week, a year. And how much electricity they make consistently.

Which is why things that make electricity, from solar panels to wind turbines to power plants, have two basic numbers. There’s “capacity,” the maximum amount of electricity that the thing can make under perfect conditions. And there’s “energy,” the amount of electricity that the thing makes over the course of time, through thick and thin.

A solar-paneled roof of a house typically has a capacity of around seven kilowatts. It can make seven kilowatts of electricity under perfect conditions, more than enough juice to power the house’s machines, appliances and devices.

But those perfect conditions, mid-day sun and completely clear skies, may be present for no more than a couple of hours daily. That’s why that solar-paneled roof, with a capacity of around seven kilowatts, only makes as much energy over the course of time as if its capacity is around one kilowatt.

Here’s another cold hard truth. The storage of electricity for later use has inherent limitations.

Before the invention of electric generators, and the development of power plants, the electric storage battery ruled. Nineteenth century generators, through the end of the Civil War, generally trickled electricity and did so discontinuously.

Zenobe Gramme changed that in 1869. Obsessively neat, he hated the messes of chemical-based batteries. So, he invented the electric generator, that is, the