Aligning EVs and the Smart Grid: Synergy and Progress

It’s understatement to say that battery and plug-in hybrid cars are not straining the electric grid today. Tesla has sold 700 cars, and there are a few thousand homemade conversions and stranded corporate leftovers (Solectria, U.S. Electricar, Taylor-Dunn, Toyota RAV4) scattered around the country.

But with more than 30 companies poised to produce cars with plugs attached in the next few years, that picture will change rapidly. To their credit, the automakers recognize that their success or failure in the marketplace depends on a grid ready to supply them with electricity.

At a forum sponsored by the Edison Electric Institute in Manhattan October 15, utility representatives gathered to talk about the smart grid and their plans for it, in almost all cases involving schemes to charge cars at night, during off-peak hours.

A number of things have to happen, the executives said. The industry needs new pricing schemes that reward consumers from charging their cars (and running appliances such as washing machines, dishwashers and dryers) at night. And they need to install smart meters (currently mostly in pilot programs) in most homes, giving consumers far more interaction with their utility bill than they have now.

The meters will allow consumers to know exactly how much each appliance and car charge is costing them, and it will give utilities not only the ability to read meters remotely but also to turn off loads selectively to avoid overload and brownouts. According to Thomas Kuhn, president of the Edison Electric Institute and moderator of the event, 58 million smart meters (at more than $100 each) will be installed by utilities through the next decade.

An Edison smart meter deployment map shows big blank spots in the center of the country, but strong pockets in California, Florida, Texas, Oregon and parts of New England. Smart meters, supported by $4.5 billion in Obama Administration stimulus spending, are only the first step in building a smart grid. The next and far bigger hurdle is modernizing transmission lines so that renewable energy generated in, say, North Dakota, can be delivered to population centers in New York and California.

Pacific Gas & Electric is a national leader in installing both smart meters and solar power. According to PG&E’s smart grid director, Andrew Tang, 3.7 million have been installed, and deployment is proceeding at a rate of 13,000 per day for a goal of 10 million installed by 2012.

PG&E was also leading utility efforts in what is known as vehicle-to-grid (V2G). People can be forgiven for mistaking it a futurist’s daydream, but the idea is that EVs plugged in to the grid can upload power from their batteries during peak periods. As the peak eases, the cars will be recharged and the consumer hasn’t suffered. No one is doing V2G commercially, but PG&E have staged successful demonstrations.

But at the forum, Tang said that PG&E now believes that V2G is at least 15 years off because of its effect on battery life. EV battery packs are set up for a finite number of cycles, he said, and repeated V2G charges and discharges could half their useful life.

In the meantime, utilities will be offering pilot pricing schemes that allow their ratepayers to profit from allowing temporary offloading of their major appliances, especially summer-use air conditioning. At the forum, both PG&E and Baltimore’s Constellation Energy described seasonal plans that allowed their customers to make as much as $200 (at a generous $1.50 per kilowatt-hour saved).

It’s plain that mutual interests will pair EV makers and utilities. As I’ve already reported, Ford is just one automaker that is trying to deepen ties and make sure that the plug-in car hits the ground running.