Hi All,
I recently added an Outback SkyBox and a 5.3kWh LiFePO battery to my existing 4.6kW Enphase grid tied system. I have sorted out the AC coupling basics but have some questions on the best way to cycle the battery and effectively use the "Grid Zero" function. My short term goal is to use my AC coupled solar power in the mornings to charge the battery. Ultimately, I plan to add an additional string of panels to the SkyBox to make use of direct DC charging.
I am using the "Net Metering with Backup" profile to allow me to use my existing NEM agreement with PG&E and to provide the option of supplying critical loads and selected circuits for operating during a prolonged power outage or a planned power interruption.
From what I can tell from the user's manuals and experimenting with different AC coupling profiles, there is no simple way to set a schedule to discharge the battery and to initiate battery charging. With the "Grid Zero" mode active the system will use battery power if available to null energy usage from the grid. In the absence of DC coupled solar production, the system will use grid power to charge the battery when it passes into the lowest Time of Use energy rate window. In my case, my preference is to charge the battery during the morning hours when there is solar production and or "Off Peak" rates are in effect and prior to the "Partial Peak" rates period that starts at 12 noon. Using grid power, the system can easily charge a depleted battery in a couple of hours.
During productive solar hours my system is generally exporting power to PG&E and I can cover most domestic loads with the exception of charging my EV. The grid zero function typically starts in the late afternoon when solar production is tailing off and household loads are rising (electric oven, microwave, lighting, TV, etc..). I am not using the full depth of charge of my battery yet as I have not completely dialed in the charging protocol, but it can usually get through the evening and night hours before reaching the low battery voltage cut off.
So my question is if anyone out there is using a SkyBox with AC coupled battery storage in this same way to zero grid power usage? If so, have you found ways to create set points or use charging "windows" that work effectively? I am struggling with what I feel is poor product documentation regarding settings and thresholds, the complete actions of some "hidden" features as well as obtuse definitions for the system's battery charging protocol. I should add that I am using a battery that does not communicate with the SkyBox with a smart BMS. It has a BMS for protection against over or under voltage conditions, but no communication bus.
Any suggestions or direction to online reference materials would be appreciated.
Thanks,
Will
I recently added an Outback SkyBox and a 5.3kWh LiFePO battery to my existing 4.6kW Enphase grid tied system. I have sorted out the AC coupling basics but have some questions on the best way to cycle the battery and effectively use the "Grid Zero" function. My short term goal is to use my AC coupled solar power in the mornings to charge the battery. Ultimately, I plan to add an additional string of panels to the SkyBox to make use of direct DC charging.
I am using the "Net Metering with Backup" profile to allow me to use my existing NEM agreement with PG&E and to provide the option of supplying critical loads and selected circuits for operating during a prolonged power outage or a planned power interruption.
From what I can tell from the user's manuals and experimenting with different AC coupling profiles, there is no simple way to set a schedule to discharge the battery and to initiate battery charging. With the "Grid Zero" mode active the system will use battery power if available to null energy usage from the grid. In the absence of DC coupled solar production, the system will use grid power to charge the battery when it passes into the lowest Time of Use energy rate window. In my case, my preference is to charge the battery during the morning hours when there is solar production and or "Off Peak" rates are in effect and prior to the "Partial Peak" rates period that starts at 12 noon. Using grid power, the system can easily charge a depleted battery in a couple of hours.
During productive solar hours my system is generally exporting power to PG&E and I can cover most domestic loads with the exception of charging my EV. The grid zero function typically starts in the late afternoon when solar production is tailing off and household loads are rising (electric oven, microwave, lighting, TV, etc..). I am not using the full depth of charge of my battery yet as I have not completely dialed in the charging protocol, but it can usually get through the evening and night hours before reaching the low battery voltage cut off.
So my question is if anyone out there is using a SkyBox with AC coupled battery storage in this same way to zero grid power usage? If so, have you found ways to create set points or use charging "windows" that work effectively? I am struggling with what I feel is poor product documentation regarding settings and thresholds, the complete actions of some "hidden" features as well as obtuse definitions for the system's battery charging protocol. I should add that I am using a battery that does not communicate with the SkyBox with a smart BMS. It has a BMS for protection against over or under voltage conditions, but no communication bus.
Any suggestions or direction to online reference materials would be appreciated.
Thanks,
Will