Question: Can the powerwall discharge to the grid? Arbitrage is the key question.
Owner who 'right sized', installed PV systems that optimized TOU+Net metering to be near zero at tru-ups. For me, we've since added 2 EVs and a pool and now drawing about 15kWH in the evenings (though still 500kwh positive during the solar year for net metering).
Scenario 1:
Super Off Pk hours -- Overnight/Early morning: Recharge EV cars and Powerwall to 100%
Pk hours SUN shine - PV system runs net positive and sells to grid at Pk rates
Pk hours negative - PV system insufficient -- Powerwall runs household needs
Off Pk hours - Powerwall continue to run household until super off pk hours
Scenario 2:
Super Off Pk hours -- Overnight/Early morning: Recharge EV cars and Powerwall to 100%
Pk hours SUN shine - PV system runs net positive and sells to grid at Pk rates
Pk hours negative - PV system insufficient -- Powerwall runs household needs
Software(or manually) toward end of Pk rate -- Powerwall DISCHARGES to 0%
Off Pk hours - Grid draw at lower rates.
--IIRC, when we started PV grid-tied systems in the past, we were explicitly NOT allowed to have batteries to avoid Scenario 2 altogether.
Thoughts?
Owner who 'right sized', installed PV systems that optimized TOU+Net metering to be near zero at tru-ups. For me, we've since added 2 EVs and a pool and now drawing about 15kWH in the evenings (though still 500kwh positive during the solar year for net metering).
Scenario 1:
Super Off Pk hours -- Overnight/Early morning: Recharge EV cars and Powerwall to 100%
Pk hours SUN shine - PV system runs net positive and sells to grid at Pk rates
Pk hours negative - PV system insufficient -- Powerwall runs household needs
Off Pk hours - Powerwall continue to run household until super off pk hours
Scenario 2:
Super Off Pk hours -- Overnight/Early morning: Recharge EV cars and Powerwall to 100%
Pk hours SUN shine - PV system runs net positive and sells to grid at Pk rates
Pk hours negative - PV system insufficient -- Powerwall runs household needs
Software(or manually) toward end of Pk rate -- Powerwall DISCHARGES to 0%
Off Pk hours - Grid draw at lower rates.
--IIRC, when we started PV grid-tied systems in the past, we were explicitly NOT allowed to have batteries to avoid Scenario 2 altogether.
Thoughts?