I wonder if there's any correlation between times someone travels 400 miles and times when they are not home... we probably need a study or something to figure it out.
The problem is, you need a full charge in the morning if you're leaving on a road trip, so then your car will not be powering your house the night before. This would likely lead to big spikes in demand the night before the start of holiday a weekend, for example.
I don't have an electric car, but I can't imagine this is a challenging problem at all. All you need is a target charge level. If you're going on a trip tomorrow, set it to 100%. If your normal commute is 20 minutes, no reason to charge past 75% or even 50%.
They were saying this creates huge problems for the grid. Let's assume people will want to destroy their car battery by draining it to power their house every night, and that this indeed supplements the need for grid storage overnight. However, when holiday seasons comes around, all of a sudden a significant percentage of homes will start demanding much higher power usage from the grid, as people co-ordinate in setting their cars not to drain power into their homes on the night before.
Sounds like the UK where everyone used to turn their kettles on during the ad breaks of popular TV shows