How PG&E Met the Challenge of Electric Vehicles

By Jonathan Marshall

The quickest way to throw away your investment in a new restaurant is to create lots of advance buzz but then fail to hire enough experienced staff. Result: disappointed customers irritated by long waits and bad service who tell their friends not to bother.

When California’s electric utilities foresaw the arrival of practical new electric vehicles as a game changer for clean transportation in the state, they vowed not to make the same mistake.

Electric Vehicle Charging

PG&E has more than 20,000 electric vehicles on the road in its service area, yet only 39 line or circuit upgrades were needed to accommodate their charging needs. (Currents Archive Photo.)

Noting that such vehicles can draw up to three times the load of a small house, PG&E’s then-CEO Peter Darbee warned in 2009, “You can see if you have three or five electric cars arrive in a neighborhood, you’re going to overload the local circuits, and that will lead to blackouts. So we see it as an opportunity, but we also see it as a challenge of significant proportions.”

Besides paying close attention to the adequacy of local infrastructure in EV-friendly neighborhoods, PG&E and other utilities have created special rate plans to incent owners to charge at night, when circuits have plenty of excess capacity.

The goal is a win-win: let owners charge their vehicles for the equivalent of $1 a gallon if they help prevent costly outages or the need to make expensive upgrades by charging off-peak.

So far, the advance planning by California’s utility’s and regulators seems to be paying off with relatively trouble-free adoption of electric vehicles — as confirmed by a joint utility report issued at the end of January.

Of the 41,100 plug-in vehicles on California’s roads through the end of October 2013, “only 69, or 0.2%, have required a service line and/or distribution system upgrade,” according to the report.

About 20,400, or nearly half, of those electrified vehicles were in PG&E’s service area. PG&E performed only 39 line or circuit upgrades to accommodate all those new clean vehicles, the report notes.

The number of needed upgrades is sure to rise over time as EV ownership takes off, of course. PG&E predicts that by 2021, its customers will own and operate more than half a million plug-in vehicles. But all indications to date are that the utility can and will handle the growing load.

One reason is PG&E’s special rate plans for EV owners, known appropriately as EV-A and EV-B. (EV-A exists for owners who use a single meter to measure usage of their car and home. EV-B is for owners who install a separate meter just for their car.)

During summer weekdays, when the grid can be stressed by high usage for air conditioning, the EV-A rate rises to a daunting 38.1 cents per kilowatt-hour for anyone caught charging during peak afternoon hours. That won’t bankrupt anyone — but only a fool would pass up the chance to charge instead late at night, when the rate drops to 9.8 cents, about a quarter of the peak rate.

These rates do the job as intended. The typical EV-A customer draws only 19 percent of their total electricity usage during peak hours, compared to 29 percent for the average residential customer. As a result, that EV-A customer uses 4 percent less energy during peak hours, even with their car, than the average PG&E residential customer.

During off-peak hours, by contrast, the typical EV-A customer uses 12 percent more energy than the average residential customer, but the grid can readily handle their demand. It’s also a net gain for the environment. Remember, their extra electricity consumption offsets what would otherwise be gasoline consumption by traditional, dirtier vehicles.

Studies of charging behavior outside California show similar encouraging trends by EV owners. All in all, the results point to a bright future for electric vehicles, as the utilities charging them earn four-star ratings for advance planning and service.

Email Jonathan Marshall at jonathan.marshall@pge.com.

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"PG&E" refers to Pacific Gas and Electric Company, a subsidiary of PG&E Corporation.
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