To V2G, or not to V2G? That is the question!
Funny how a topic can suddenly appear on your mental radar, break wide open (with help) and – at least in the smart grid’s case – instantly tie in to current events. Gets me up in the morning.
Yesterday one reader asked if anyone knew of a source for the size and electricity requirements of the U.S. fleet of cars and light trucks. Implied between the lines: what’s the potential load and what’s the potential to harness that much storage?
Lo! a response came in that cracked open the vehicle-to-grid (V2G) space for me. And that setup a delicious dilemma: go through with my planned dinner with my girlfriend tomorrow night, or fly to San Diego for Friday morning’s V2G panel discussion, part of the American Association for the Advancement of Science’s annual meeting.
(Decisions, decisions. Whether to maintain a once-in-a-lifetime romance or get up-to-date on V2G? But I digress.)
Should you be San Diego-bound, or looking for fresh sources on this topic, the panelists Friday provide a real roadmap for further enquiry.
They include: Willett Kempton, a University of Delaware professor who has examined V2G’s potential for stabilizing the grid and providing load and storage for renewable energy; Kenneth Huber, with PJM Interconnection, who has looked at electric transportation’s implications for the grid; Jasna Tomic, with CALSTART, has weighed hurdles to implementation; Tina Kaarsberg, U.S. Department of Energy, has looked at alternative electric transportation (trucks, trains); Jeff Stein, University of Michigan, has worked on V2G’s interactive nature; and Ray Boeman, Oak Ridge National Laboratory, has looked at state-of-the-art technologies and that much-sought-after but often elusive route, “the path forward.”
That’s almost enough to make a man give up on love. (But not quite.)
So, in taking a cannonball-like plunge into the deep end of the V2G pool, I came across several researchers whose work is worthy of note. I thought I’d begin with a column on the vision of V2G, based on one researcher’s calculations of their potential impact. The numbers are eye-opening and go a long way to explain why a lot of very smart people are expending a lot of calories and dollars to push the envelope in that direction.
My enquiries yesterday included requests for interviews with top researchers, so I promise to bring you the fruits of those conversations soon in this space.
So, to the vision. Kempton, at the University of Delaware, has coupled the nation’s electric utility system and the light vehicle fleet as “two massive but separate energy conversion systems.” Nearly 10,000 utility generators produce more than 600 gigawatts (GW). More than 176 million cars and light trucks produce more than 19,500 GWm (m stands for mechanical energy). That’s 24 times the capacity of the electric generation system.
As the automotive world explores electric vehicles (EVs) and renewable energy sources are tied into the grid, in Kempton’s words, “the economics and management of energy and power in the light vehicle and electric systems make their convergence compelling in the early decades of the 21st century.”
EVs can provide electricity storage and quick-response generation to the grid, electricity will complement and displace gasoline in the fleet and automated controls will optimize the transfer of energy between the two giant systems, given their different but compatible needs based on time of day.
In a paper titled, “Vehicle-to-grid power implementation,” in The Journal of Power Sources, Kempton calculated that one-fourth of the U.S. fleet produces mechanical energy equivalent to the entire output of the nation’s electricity generation. “Capital costs to tap vehicle electricity are one to two magnitudes lower than building power plants,” Kempton wrote.
“The average per kWh cost of vehicle electricity is considerably higher and design lifetimes are one to two orders of magnitude lower,” Kempton wrote, “but the critical insight…is that vehicle electricity is competitive in specific electricity markets.”
Kempton examined the four relevant "markets," by which he means baseload, peak, spinning reserves and grid regulation. He found that V2G is not suitable for baseload, in some cases it may be suitable for peak power, it is competitive for spinning reserves and highly competitive for regulation -- the short but frequent requirements of the grid to keep frequency and voltage steady.
In the future? Storage by V2G of intermittent renewable resources.
I’m speaking soon with a gentleman who has invented a charge controller that makes this future scenario possible today.
So, we’ll leave it there for now. I just wanted to begin with the premise and the promise, quantified. Feel free to jump in, folks, the water's fine. And there are multiple paths of enquiry opened here.
Intelligent Utility Daily