I've been AWOL for a while, sorry about that. I'm putting together my first online course, on Zero Net Energy Homes, for the NESEA Building Energy Masters Series. You can read about it here:
Meanwhile, the House 5 PV system just passed 8,000 kWh generated! And we have a surplus credit of over 3,700 kWh, which we can allocate to another meter.
I have plans to post more about the hot water question, especially on heat pump water heaters, and also on the insulating blinds. Stay tuned!