OPINION

It’s the iron-air battery.

“I’m an electrical engineer and we had a presentation on the air - iron battery to managers at a GRE meeting,” Haman said. “I think it looks promising. I like that the materials are not rare materials.”

Reliability is all about batteries. Batteries need to store electricity to make it available when renewables aren’t working — when it’s cloudy or the wind isn’t blowing.

The batteries being used now are lithium-ion batteries. They are like giant cell phone batteries. Lithium-ion batteries are good for cell phones and even electric cars. But they aren’t very good at storing a lot of energy for very long. In fact, the big utility scale lithium-ion batteries are currently good for only about four hours.

That’s a reliability problem. The Republicans were right!

The Republicans were short sighted!

All of these states are counting on electrical power that will be reliable for retail and wholesale customers while they are heading toward their goals and when they get to them.

I’m partisan and my knee is generally set on autojerk when it comes to positions taken by the Minnesota GOP. To get beyond my partisanship, I decided to call the CEO of Runestone Electric Association. REA has been my electrical co-op for the past 35 years and I’m proud to say that.

I’d never spoken to Al Haman before, but I trusted that whatever he told me would be based not on party politics, but what was good for REA patrons. We chatted a bit about last summer’s storms which caused significant multi-day power outages in a large swath of REA’s service area.

Then I asked Haman what he thought of Minnesota’s new renewable energy mandate.

“We are responsible to assure the continued supply of electricity for our patrons,” he said. “Intermittency is our big concern with that legislation right now.”

Getting your electricity intermittently, of course, means your electrical system is unreliable. But, REA is one of 27 co-operatives which get their electricity from Great River Energy, or GRE. GRE had a potential solution to the reliability-intermittency problem on the drawing board six months before the Minnesota Legislature voted in the 100 percent by 2040 law.

In the 1960s NASA, the moon-shot people, developed some metal - air batteries. There were zincair batteries, aluminum batteries, and iron - air batteries. The research was dropped. Then, in the last decade, Form Energy improved on the technology of the iron - air battery. The iron - air battery now will stay charged for 100 hours. That, ladies and gentleman, will take care of the reliability issue.

In September of last year, Great River Energy announced it would be the first utility in the United States to install an iron - air battery storage module.

“The Cambridge Energy Storage Project will be a 1.5-megawatt, grid-connected storage system capable of delivering its rated power continuously for 100 hours — far longer than the four-hour usage period available from utility-scale lithium-ion batteries today,” GRE announced in its Sept. 15 press release.

“While this project will be a relatively small resource on the grid, it is a leap forward for longduration storage,” said GRE Vice President and Chief Power Supply Officer Jon Brekke. “We are optimistic that this type of resource could be very valuable as the electric system continues to evolve.”

In addition to holding a charge 17 times longer, the iron - air battery is expected to be 20 times less expensive than the lithium - ion battery. That’s because, as Haman pointed out, iron is not scarce. Lithium is.

In late January, Xcel Energy — Minnesota’s largest utility — followed GRE and announced it too would be installing a Form Energy iron - air battery