Portland, Oregon wants to be a hub for electric vehicles and early electric-car adopters.

With the city focused on attracting companies and making the region a center for electric-vehicle launches, test fleets, and even EV tourism, it begs the question: how many people in the Portland area, how soon, could be driving electric vehicles before it makes a significant difference to the grid? Will Portland's utility need to increase capacity?

That's what we asked Portland General Electric (PGE) president and CEO Jim Piro, at the opening of the city's Electric Avenue, a block of chargers of different brands and types for testing and demonstration.

Renault-Nissan CEO Carlos Ghosn has bullishly targeted electric cars to be 10 percent of the market by 2020. And he might not be too far off the mark—for Portland, that is.

While projections vary wildly, most anticipate that plug-ins will be 2 to 5 percent of the U.S. new-vehicle market in 2020. But in Portland, according to those conservative projections from the utility's integrated resource plans, 10 years from now, one out of every 10 new vehicles registered in Portland could be a plug-in.

That's probably higher than you might have guessed. But the Toyota Prius has twice the market share here that it has nationwide. And more than 300 Nissan Leaf electric cars—that's more than a tenth of the Leafs Nissan has sold outside California—have come to rest in Portland.

Portland General Electric (PGE) CEO Jim Piro

Portland General Electric (PGE) CEO Jim Piro

"We think it's going to take them some time to scale up manufacturing," said Piro, who thinks the area has the potential to purchase even more electric cars, though he fears the supply and breadth of models simply won't be there.

"So for us, by then, that would be about 170,000 vehicles in the Portland metro area," summed Piro, referring to the ten-percent scenario, or about 50 megawatts of additional capacity by 2020—barely enough for the utility's load to change, he said, especially if vehicles charge at off-peak times.

But for most or all vehicles to switch to electric, Piro estimates that it might get a little tighter. Considering a total of 500 megawatts, Piro says, "My guess is that we'd have to add a little bit of generation, but not a lot...It would add up to about 1000 megawatts off-peak, so that would be pushing the system if we tried to do that all night."

"Now our hydro capacity is tapped out, so we can't count on that," said Piro. "But frankly, that's like one natural-gas plant, and a lot of that can be done off-peak."

Admittedly, in some regions, that might mean higher production at coal plants. But U.S. utilities are more prepared than you might think. Piro likened the load of an electric-car charging station to running two hair dryers at once, or the load of a clothes dryer. Other experts compare the load of a charger to having four plasma TVs turned on simultaneously.

And while so-called 'Prius clusters' (a concentration of early adopters in the same neighborhood) remain a concern, utility companies are working to upgrade neighborhood transformers before that becomes an issue.

Piro is hoping for a surge on the commercial side, too. "If we got to 20 or 30 percent penetration of EVs, I think that would be pretty cool," he said, near a Staples' Smith Electric delivery van, suggesting that the utility already has a long-range plan if the numbers skew so favorably for EVs.

"There are a lot more 'off-residential' applications where electric is going to make a lot of sense."

UPDATE: PGE contacted us to clarify that the numbers considering ten percent EVs in ten years aren't Piro's projections but from one of several potential scenarios in the utility's integrated resource plan. A sentence above has been edited to represent that.


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