Electric car batteries can do more than power electric cars. They can send current to homes and buildings, or send it back to the grid when demand is high. Some experts even believe EV batteries might one day boost the prominence of renewables by storing the energy from wind and solar farms.
The idea of so-called “vehicle-to-grid” schemes inevitably stirs debate among engineers. But make no mistake: The concept has a huge following. Googling the term “vehicle-to-grid” yields an astounding 526 million hits. That’s one reason electric utilities, auto manufacturers, and university researchers are all studying the concept.
We collected photos and diagrams from ongoing vehicle-to-grid programs. From pure EVs to plug-in hybrids to wild-looking concept cars, we offer a peek at some of the vehicles that could one day power your home.
Click on the image of Willett Kempton to start the slideshow.
Willett Kempton of the University of Delaware has been a driving force behind the idea of vehicle-to-grid (V2G) technology. In 2013, Delaware teamed with NRG Energy to launch the world’s first revenue-generating V2G project. Here, Kempton is shown with a Honda Accord Plug-In Hybrid that’s being used as part of a demonstration project by the university. (Source: Honda)
Cap'n, this is nice in theory, but not really practical. The issue with plug in electrics today is range. One good aspect is that they can be charged off-peak. I guess that, in an emergency, the car battery could be used to supplement the grid. On the other hand, that electricity will not be available for transportation, the vehicle's primary purpose. If you have a car like the Volt, that might not be a problem, because there is a ICE to charge it. On the other hand, the Volt's battery is not that large. The vehicles with the large batteries, pure EVs, which would be most useful in this scenario, are the ones for which this is the biggest problem.
It is much cheaper to site batteries or fuel cells in houses, or at substations. My understanding is that many new homes in Japan are powered by fuel cells. This is much more reliable. Take slide 7. What happens if the building is drawing from the cars and someone needs to go somewhere. The car battery will be depleted, and the driver will have to wait until it can be charged again.
It is true that EVs can be useful in terms of renewables. The whole idea of being able to store energy from renewables is advanced if that energy can be used to charge vehicles. There should be a cost advantage for doing so.
"What happens if the building is drawing from the cars and someone needs to go somewhere. The car battery will be depleted, and the driver will have to wait until it can be charged again."
Another question springs into my mind, what happens to the battery life? It depends on the value being extracted from the battery by the grid. The controllers designed to use in the EVs are intelligent, so that battery life can be utilized to its maximum potential. Will the grid also work intelligently or will it extract all the power it can and leave the driver stranded with a damaged battery.
I guess a better alternative is utilizing this money and making a static energy setup instead of a moving car.
This is a really interesting slideshow, and I am not sure I agree with you, naperlou, although you have a really good point. But when I was researching a recent story on the Army and its use of renewable energy, I learned about how they are plugging Army vehicles into microgrids they have designed (that use renewable energy as part of their source of electricity) to recharge electric cars. This sounds like the reverse of the concept here, but also if I understood them correctly the connection went both ways--to charge and also to send energy back to the grid. So it is quite feasible that this could work.
I am not sure how the bidirectional power is going to work. Don't most power companies charge their customers a different (higher) rate for power they send to customers than the rate they pay for power supplied to them? So the customer will in effect end up paying the power company for the previlege of helping them supply power by using power from their EV battery! Sounds like a winning situation for the power company and a loosing situation for consumers.
Also I agree with Naperlou on the possibility of leaving EV owners without a useable vehicle.
Charles, thanks for this story. naperlou, i have one disagreement with what you said: this is a lousy idea even in theory!
To me, the idea of using your PEV to power your house is kind of like running your house off of a bunch of D-batteries. Eventually, the D-cells will be drained, & then you're left with a grid-connected house and a bunch of dead batteries. So, if your Leaf can power your (Japanese) house for a couple of days, where are you after that couple of days? You may have saved some money by avoiding peak electricity charges, but now you can't go anywhere!
The flaw in this scheme, to me, is that the EV car can only get its resupply from the grid; it has no independent electricity generation. Using an analogy, it's a pressure tank on an air compressor; it only gets filled at the spot from which it's drained, and the compressor has to be running or the tank runs out and you get no more air. The Volt does have its own generator, yes, but generating that electricity from the Volt to replace that which was sucked out onto the grid is a considerably less efficient process than what can be generated by the grid. Either way it's a loss: either you lose range to the grid or the whole system loses efficiency.
If somebody can enlighten me with a use case that makes sense, please do so!
But if the goverment is willing to offer our money then agency's and univerisities will take and waste it studing ideas that a 4yr old could tell you do not pass the smell test.
I do not really need to explain why this is a bad Idea other have and quite frankly common sense of a 4yr could tell you as well.
But it is another way they can try to say see look how good an EV fleet would be we.
EV's need to stand or fall on their own, If they are cost effective then they will stand. If they are not then until they are we should let them be a novelty, and not force all car buyers and taxpayers to pay to support them.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies.
You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived.
So if you can't attend live, attend at your convenience.