I got PTO activated last week and since turning it on, I've just monitoring our usage pattern. Setup is 12kW System + 2 PW. Tesla settings is self-powered mode with 80/20 reserve split. Average house consumption is ~18.7kWh with solar being ~37.2kWh (28% to home, 25% to PW, 47% to grid).
My usage pattern seems to be as follows:
- Solar starts generating ~8AM
- Solar exceeds house needs ~9AM starts charging batteries
- Batteries fully recharged by ~11AM-12PM
- From there, all excess is sent to grid
- ~6PM Solar generation ends
- From 6PM to 8AM next day, I am running on battery
- Battery usually reaches ~65-70% capacity by 8AM next day when solar starts generating again.
- We have 1 EV which I charge during the day and has no effect on batteries (8-9kW needed when charging vs ~9-10kW from system)
- I can run AC during the day with the same effect (5-6kW needed when running AC vs ~9-10kW from system).
We plan on adding another EV in 3 years and perhaps switching to electric water heater but other than that, we have no need to do anything with the grid but are we maximizing our return?
Should I leave it in self-powered mode or switch to time-based control? I'm on EV-A2 for PG&E so rate schedule is
- Off-peak 12:00 AM - 3:00 PM - $0.25kWh
- Mid-Peak 3:00 PM - 4:00 PM - $0.41kWh
- Peak 4:00 PM - 9:00 PM - $0.43kWh
- Mid-Peak 9:00 PM - 12:00 AM - $0.41kWh
Do I have any reason/need to pull from the grid and incur NBCs? If I for some reason do pull from the grid, does it just net against the kWh I've exported and I just pay the NBC? (e.g. I've exported say 30kWh of peak power and I consumed 5kWh today. PG&E wouldn't charge me $0.43kWh, just the NBC of the 5kWh and my 30kWh credit goes down to 25kWh?
My usage pattern seems to be as follows:
- Solar starts generating ~8AM
- Solar exceeds house needs ~9AM starts charging batteries
- Batteries fully recharged by ~11AM-12PM
- From there, all excess is sent to grid
- ~6PM Solar generation ends
- From 6PM to 8AM next day, I am running on battery
- Battery usually reaches ~65-70% capacity by 8AM next day when solar starts generating again.
- We have 1 EV which I charge during the day and has no effect on batteries (8-9kW needed when charging vs ~9-10kW from system)
- I can run AC during the day with the same effect (5-6kW needed when running AC vs ~9-10kW from system).
We plan on adding another EV in 3 years and perhaps switching to electric water heater but other than that, we have no need to do anything with the grid but are we maximizing our return?
Should I leave it in self-powered mode or switch to time-based control? I'm on EV-A2 for PG&E so rate schedule is
- Off-peak 12:00 AM - 3:00 PM - $0.25kWh
- Mid-Peak 3:00 PM - 4:00 PM - $0.41kWh
- Peak 4:00 PM - 9:00 PM - $0.43kWh
- Mid-Peak 9:00 PM - 12:00 AM - $0.41kWh
Do I have any reason/need to pull from the grid and incur NBCs? If I for some reason do pull from the grid, does it just net against the kWh I've exported and I just pay the NBC? (e.g. I've exported say 30kWh of peak power and I consumed 5kWh today. PG&E wouldn't charge me $0.43kWh, just the NBC of the 5kWh and my 30kWh credit goes down to 25kWh?