Wake us when he uses them to charge his Tesla tractor.
From Hansen’s interview with Bloomberg News:
Q: What do you do in your own life to cut emissions?
A: We have covered our barn roof with solar panels, so we’re generating twice as much electricity as we use. And as soon as we can afford it we will put in geothermal heating. Then our property will be very energy efficient. We investigated a windmill, but it’s not allowed.