what I learned today - or why my powerwall doesn't fully charge from solar every day

[jgleigh]

@DarylLafferty wouldn't it be easier to put it into Self-Powered then?

 

[DarylLafferty]

@DarylLafferty wouldn't it be easier to put it into Self-Powered then?

In Self-Powered the system would use the battery as much as possible to minimize draw from the grid. It would possibly mean not having enough to survive Peak time, and I would end up paying a higher price, besides exercising the battery more and shortening its life.

Since I am grandfathered into net-metering, I would rather let my utility (SRP) be the battery for most of the time, except during Peak.

 

[Vostok]

In Self-Powered the system would use the battery as much as possible to minimize draw from the grid. It would possibly mean not having enough to survive Peak time, and I would end up paying a higher price, besides exercising the battery more and shortening its life.

With 2 x EVs, my PW2 is fully discharged (down to the 10% minimum I set) almost every single day. The only times it doesn’t is when we are away on holidays. And with my relatively modest solar array, the PW2 gets fully charged on only 66% of days.

So looking at my stats, my PW2 is cycled on average 0.57 times per day which is quite a lot. My capacity is already down to 10 kW after 4 years, and I am nailed-on for a warranty replacement in 2-3 years time.

In comparison, my Model 3’s battery is cycled on average 0.047 times per day, or once every 3 weeks. It should last a very long time.