DeaneG said:
planet4ever said:
Course, it might be more efficient to put solar panels on your own roof. ... Just a thought.
I agree but payback = 7 years and probably moving = 3 years.
I remember, now, you said that once before in a different thread. To which I think I responded that you can sell the house for more if it has solar panels.
[Can you guess? I'm a bit of a solar nut.]
DeaneG said:
I am using a guess of 2.5 miles per AC kWh (wall to wheel efficiency, heavy car, lead foot).
I used to have a lead foot, too, until I drove a Prius. It really does encourage you to drive more economically, and I think the Leaf will do the same.
DeaneG said:
Everyone else seems to be calculating based on battery to wheel numbers. But the power comes from the wall, not the battery.
Tesla roadster wall-to-wheel numbers are in the 300 to 400 Wh/mile range (3.3 to 2.5 mile/kWh).
I agree that wall-to-wheel is the right way to think about it, but I don't think the Tesla's numbers are comparable. Tesla is an out-and-out sports car, driven by rich sports car drivers. And their batteries are basically off-the-shelf laptop computer batteries.
Look at it this way: Nissan claims 70 to 130 miles on a 24kWh battery. (OK, less in some extreme situations, like stuck in a traffic jam for 8 hours with the AC on full.) Wall to battery efficiency is probably going to be between 85% and 90%, so 27-28kWh max from the wall to charge fully if 24kWh is usable - many people believe that is 10%-20% high. Your 2.5 miles/kWh looks like an absolutely worst possible case. I think 3.5 is much more likely, and it could be as high as 4.0. If you don't want to believe Nissan, consider that GM is staking its reputation on 40 miles from 8kWh. Do the math.