Sol-Ark 15K dropping PV

[Oldphile]

If you set your TOU setpoints to 95% as suggested by @Brucey then pv will only charge to that before pushing the rest to grid. Think of the TOU setpoint as the "discharge to...." setpoint. The Sol-Ark will even "sell" out of the batteries down to the TOU setpoint.

In other words, "battery first" will come into play until the batteries get up to the TOU setpoint, then PV gets pushed to AC until TOU calls for a higher

@Carlos_Sol-Ark has set it to 99% to try that.

 

[DIYrich]

Turn off grid charging. Let the solar fill batteries as much as it can. Let your load drain batteries as much as it can. That is the most efficient way to use batteries, unless you have time of use rates. Solar first, battery, last is grid.

 

[Cmiller]

Turn off grid charging. Let the solar fill batteries as much as it can. Let your load drain batteries as much as it can. That is the most efficient way to use batteries, unless you have time of use rates. Solar first, battery, last is grid.

Unfortunately there isn't one "cookie cutter" setup that "is the most efficient way" to run every system! There are multiple things that factor into what makes the most sense and is the most efficient. On HV DC bus all-in-one inverters like the Sol-Ark, Eg4, etc. you have a lower efficiency when pushing power to and from the batteries, than when you are keeping everything running between PV and AC. So if a person has a net metering agreement that is a 1:1/kWh:kWh within the billing cycle, and at the end of the billing cycle only the difference is billed or credited, it usually makes the most sense to actually not even cycle the batteries and use the grid as a battery with the physical batteries there for backup when grid goes down! The efficiency when keeping the batteries full for backup and using grid as your battery is low to mid 90s % (probably 92-95%) and when you push most of your produced power into the batteries then draw it back out overnight your efficiency drops to more like 80-85%!

A few things that factor into what "is the most efficient" setup:

• Net metering/ net billing agreement details
• price per kWh for buying/selling from/to the PoCo
• how much battery storage one actually has vs. daily kWh usage
• how much PV one has vs. daily kWh usage
• what kind of system equipment one has (eg. AIO, inverter with charge controller separate, AC coupled, etc.)

 

[Oldphile]

a net metering agreement that is a 1:1/kWh:kWh within the billing cycle, and at the end of the billing cycle only the difference is billed or credited

This is what I have. I'm only cycling the batteries to see how the batteries and system perform. I got batteries solely for backup. I would join Connected Solutions, but the only battery Eversource accepts into their program is Enphase.