Vehicle-to-grid: Genius or waste of energy?

September 27, 2011


A professor at the University of Delaware has patented a vehicle-to-grid (V2G) technology for parked electric vehicles to return power to the grid and teamed up with NRG Energy to commercialize it.

Professor Willett Kempton, who has been testing V2G technology that lessens the load on natural gas plants, told the New York Times utilities would not be interested in buying electricity from individual cars but from groups of perhaps 100 vehicles.

The idea is not without its critics.

The only way this will take off is for users to have a financial incentive to allow the power company to do this, i.e. the power price during peak demand must be so high that it’s cheaper to deplete your EV battery rather than draw from the grid,” writes hackertourist on listserv slashdot.

Ancillary services could fetch $3,000 a year for EV owners, CNET Green Tech reported the Federal Energy Regulatory Commission chairman saying last year.

Others are concerned with vehicular range. “What happens when you want to drive the car and the battery isn’t charged because the power has been returned to the grid?” writes mcavic on slashdot.

Meanwhile, V2G appears to be heading for a big push in the Japanese market, reports Jim Motavalli in the New York Times, possibly due to its potential during blackouts. Nissan, Mitsubishi and Toyota are all developing V2G systems expected to reach customers by the end of 2012.

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A few points: 1) Studies have shown that even during peak rush hour time only 10% of total vehicles are on the road and therefore unavailable, 2) The V2G system allows the user to keep a minimum driving distance so that the battery never discharges more than 80% or so, 3) The ancillary service market does not require deep cycling which deteriorates the battery, but rather high frequency, shallow charging and discharging. Genius idea

Posted by Cleangreen1 | Report as abusive

Great if you kept your SUV full of gas parked in the garage. I live 30 minutes from the nearest local hospital and 1 hour from a major regional hospital.

Posted by canadapatriot5 | Report as abusive

My Leaf has a range of between 90 and 100 miles, depending on how heavy my foot is. It charges itself at night when electricity rates are 33% of what they are during the day. My average commute is 25 miles. I could comfortably give up half of my total capacity to load leveling during the day. The power co. would also need to figure reduced battery cycle life into the pricing structure, and I would need a mechanism whereby I can tell them NOT to take power in a particular instance when I need extraordinary range.

With the right pricing for my electrons, it could work.

Posted by gregbrew56 | Report as abusive

what an awesome idea i love these vehicles

Posted by colise | Report as abusive