We have solar, and we are looking at installing a heat pump water heater in the next month or two in order to take advantage of the US tax rebate that is coming to an end at the end of the year. (We also already have a heat pump for heating and cooling). 

I’m hoping that with the heat pump water heater that I can use excess solar at midday to heat up the whole hot water tank and then hopefully that will last for 24 hours until we  do it again at midday the next day. 

We frequently have extra solar in the middle of the day and yet we draw from the grid at night (see the screenshot of our June Usage). We have two EV‘s and often times the EVs are not home during the day when we’re at work, so we aren’t able to take advantage of the access solar at that time. 

I would love for the HPWH to help cut down on the months where I am both exporting a bunch of power (and therefore wasting it), and also importing power. 

Is anyone using their heat pump water heater like this, by having excess solar heat up a tank of hot water once a day at midday, and then using the hot water over the next 24 hours? 

I am in Northern California PG&E territory.  9.3kwh, two powerwalls. Right now, we have a 37 gallon hot water heater fueled by natural gas. We have two parents and four kids. I actually can’t think of a time when we ran out of hot water for showers but nevertheless, I would probably upgrade to a 50 or 60 gallon.

Heat pump water heater - excess solar question