Too many of the scenarios for electric cars on the smart grid talk only about the relationship between the single car in the home and the grid. These relationships are not the most important ones, and will not determine the successful integration of millions of electric vehicles into the grid. The relationships that matter are those between the cars and their drivers, their family plans, and the other cars in the household. Car software will be even more important than car performance.
The successful car software will begin learning about its owner from day one. It will learn the schedule of its driver, and how far he drives each day, and when. I say learn, because the successful car will pick up this information without requiring programming. This will mean that programming will normally be by exception.
Over time, the car will learn how often these standards are broken. If periodically during the week, the family drives over to Grandma’s house, four miles away, then the car must have reserves for an nine mile drive. If that drive is the only trip during the week that piles the entire family into the car, then those nine miles must be for a more heavily loaded car. Each bit of this learning can affect how and when the car buys electricity.
A challenge in any household is managing the family schedule. Soccer games and little league responsibilities may be spread over the house. A car may leave home to park at the airport for a week. The whole family and all its cars may plan to drive across town to grandmother’s house on Thanksgiving. Just as the family must coordinate their schedules so no one is left behind, so the cars must coordinate their charging schedules, so each car is charged up when needed, and the electricity was purchased at the lowest cost to the consumer.
There are different ways to coordinate the cars. The family may manage a common calendar, perhaps on a flat screen mounted on the refrigerator door. The common family calendar may interact with family PDAs and cell phones. The family cars may get their target schedules from this common calendar. Alternately, the cars may be able to “see” each other, perhaps using Blue Tooth. Somehow the cars must negotiate priorities. Does Mom or Dad get top priority for charging? Does the college kid who works at night get top priority in the late afternoon? If grid power is expensive, can that college kid buy power from another car? Will the relative efficiency of each car’s battery be factored into those decisions?
So far, we have not moved beyond the garage—except to the refrigerator schedule.
In the well functioning household, all the parts need to work together. Thanksgiving day laundry with an electric dryer may anticipate that Thanksgiving day trip. Hair dryers can be anticipated in the hour before departure. In-house generated power may be part of the decision process. Weather reports may help predict the amount of in-house power that will be generated as well as what the external power prices may be.
The interfaces that make this work are not engineering interfaces. They are human interfaces. The interfaces that make this work are cross-cutting interfaces. They will not be managed by end to end controls.
The team that does this well will have the killer app for cars...