This was the post I started writing a couple days ago until the first paragraph just metastasized to fill up the page. Once we have more than a few electric cars in town, then those cars will be potentially the biggest stress on the grid.
The peak stress on the power grid starts during the afternoon, during heat-of-the-day air conditioning and work, but it continues through the early evening. Offices are still turned on. Programmed houses are kicking in with their air conditioning in preparation for their owner’s arrival. Families are cooking dinner. The power grid is still working nearly as hard as it can.
Now let’s posit the electric cars coming home, drained from a day of driving. Perhaps they were doubly drained, used to carry their office buildings during the afternoon brown-out. What will people want from their cars next….
- To sit in the garage overnight, slowly charging.
- To be ready to drive 15 miles in twenty minutes when I go get one last kid from athletic practice.
- To be at least half charged and ready for anything in two hours when the baby sitter arrives and mom and dad head out for an evening on the town.
- To quickly get to at least a 40 mile range in case I get an emergency call from the nursing home, and thereafter just be sure to be ready for the morning commute.
- To get a charge for 15 miles by 8:15 when I head to choir practice at church. Better make that 25 lest we stop for coffee afterward.
- It's two hundred miles to the beach and we plan to take full advantage of the expensive week-long rental by getting there tonight! Kids, grab your bags, we are leaving in 20 minutes. Oh, and the car needs a full quick-charge, no matter the expense.
Gasoline handles all these scenarios. Many of them involve discretionary electricity purchases during the early evening peak. We will never solve these problems at the level of machine-controls. We need time of day pricing, to allocate the scarce resource. Just as many restaurants offer Monday-night specials, we need day-by-day pricing, to encourage people to choose when to schedule their evening activities. Electric cars will require live power pricing, by the minute, and by the day.
Let’s consider driving the electrical car further into our lives, and further into our infrastructure. Sometimes I will want to charge my car when I am not at home. This will require that cars identify who they are at the plug.
- When parking downtown, I want to plug in my car. I may want to choose between a quick visit, for a cup of coffee, and an all-day back-to-school shopping event.
- The Green Garage™ offers locally generated wind power for re-charging at its own special rates that vary with the wind. Having been burned once, I want to check prices before I leave the car.
- When I go over to your house for dinner, I want to plug in. Being a polite guest, I of course want the charges to go onto my own bill.
- The whole family gathers in the next town for Thanksgiving dinner. All cars are drained, and need to recharge over the next five hours except for the college kid, who arrives at the last moment, and leaves as soon as he can. Grandpa decides to overrule all normal agreements and cover all the charges for cars plugged in at his house.
The technical feat of creating amazing batteries and lightweight materials, however astonishing and inspiring, will be undone without the capability easy interaction with the lives and aspirations of those who drive the cars. Electric cars will require powerful intuitive systems interfaces, able to learn their owner’s tastes and habits. These systems can only interact with the power grid through simple standard economic interfaces.