I'm in California, near Tesla Fremont, so to me summer is a silly concept, and I have no idea when it begins and ends. At work all day yesterday I was bombarded with a cold wind from the north. Just now, I saw on Powerwall Tesla web page, deliveries will begin in summer. It doesn't say which summer, so let's at least be optimistic and try the presumption "the most close one in the future". If we look at California's definition of summer, let's go with: not rain season. So, that's effectively about a decade right now. I'm ok with that interpretation. But it seems very nonspecific. Perhaps what I'd prefer is a more precise claim of intent and prediction on the part of Tesla as to when it would ship, such as a count of days, or even a calendar month type thing, which has more definition. Elon Musk comes from South Africa, so summer there could also be never-ending, or it may be one of those places that has its summer, but since it is in the southern hemisphere, that would be around January.