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Quick Take: You've heard me complain that we don't spend enough effort on "smart charging" – the concept of varying the rate of EV charging to accommodate different conditions. So you won't be surprised that I'm very pleased that AeroVironment has integrated grid-friendly technology into its charging stations. Licensed from Pacific Northwest National Laboratory, the technology monitors grid frequency and varies its charging rate accordingly. It can even stop charging entirely if it detects the kind of rapid frequency drop that indicates a likely fault.

As renewable penetration increases, it will be more and more important to find shock absorbers to adjust to the constant fluctuations of intermittent generation. Read the press story below to learn about the "triple win" this kind of approach offers to utilities and their customers. - By Jesse Berst

Advanced plug-in EV charging systems provider AeroVironment and DOE's Pacific Northwest National Laboratory (PNNL) have announced an agreement they say will result in wider adoption of PEVs by using them to help make the electric grid more stable.

"We are working to broaden the adoption of plug-in vehicles to help achieve America's environmental, economic and energy security goals," said Wahid Nawabi, senior VP and general manager of AeroVironment's Efficient Energy Systems (EES) business segment. "While easily and reliably charging PEVs, this grid-friendly charging system will also improve grid performance, turning PEVs and their chargers into a valuable solution to a broader challenge."

Under a licensing agreement with  the company, PNNL technology can be used to aid in grid stabilization by constantly monitoring the grid's alternating current frequency and varying car charging rates in response. If there is a sudden drop in grid frequency, the charging system will stop – a function that acts as a "shock absorber" for the grid. While those quick drops are relatively small, they signal that a fault has happened on the grid and load and power generation is out of balance. Balance is restored when the load is scaled back.

AeroVironment will use PNNL's technology in a new prototype version of its Level II charging systems.

Traditional power plants conduct continuous electricity generation adjustments to ensure an almost constant grid frequency. But as power generation grows from variable energy sources like wind and solar, the overall capability for power plants to effectively respond is reduced. The frequency-responsive technology from AeroVironment and PNNL adds grid frequency support capability to vehicle charging stations.

The two companies share the belief that when millions of plug-in EVs are charging at once, adjusting the overall charging rate can help control grid frequency, which should support integration of variable energy sources.

"These technologies will result in a triple win," said Dr. Alec Brooks, chief technology officer for AeroVironment's EES segment. "First, by reducing the cost of integrating variable renewable generation reduces electricity costs for all ratepayers. Second, plug-in cars can be powered by renewable generation that might not have been possible to add to the grid without the charging rate flexibility offered by vehicles and this technology. Third, the reduced cost of electricity to plug-in vehicle drivers will further improve on the cost advantage of driving on electricity as compared to gasoline."

PNNL lead engineer Michael Kintner-Meyer explained further. "If a million owners plug in their vehicles to recharge after work, it could cause a major strain on the grid. The Grid Friendly Controller could prevent those peaks in demand from plug-in vehicles and enable our existing grid to be used more evenly. And our studies have shown that those who use the technology could save $150 or more a year on their electricity bill, and they could potentially receive rebates for providing shock absorbing services to the grid operator."

Jesse Berst is the founder and chief analyst of Smart Grid News.com, the industry's oldest and largest smart grid site. A frequent keynoter at industry events in the U.S. and abroad, he also serves on advisory committees for Pacific Northwest National Laboratory and the Institute for Electric Efficiency. He often provides strategic consulting to large corporations and venture-backed startups. He is a member of the advisory boards of GridGlo and Calico Energy Services.