Help on Grid Tied system design

[PeteYates]

Hi all, New here and located via Will's YT channel. Awesome content Will.
I am seeking help on designing a grid tie battery system...all help welcome!
I have already designed and been approved (twice) by APS (AZ power) for a grid tie system but didn't execute. Watching Will's channel, I need to up the system with battery...this is where i need help.
Background
1) APS time of use plan with a 3 hour peak usage premium (4-7pm). I use a peak of 10kwh during this window even with pre cooling
2) Max daily usage is approximately 250kwh (summers with temp over 100). Min daily usage is about 90kwh (winter). A/C drives most consumption
3) Already approved for 36 400W ground based panels with 15kw inverter

Goal - Solar with ROI!
1) Reduce overall consumption by about 50%
2) Eliminate the time of use consumption charge (as much as $250/month)

Constraints
1) Ground based system that can accommodate approximately 32 400W panels...approx 14kw system max. Possible later expansion though APS do not like residential over 15kw.
2) Partial shading on some panels during the day so a preference for micro inverters
3) 400W main panel

Questions
1) What size battery do I need?
2) What kit do I need to manage battery usage during peak hours (i.e. how do I prioritize battery supply over utility during peak hours).
3) What else do I need to think about

Many thanks to all

 

[k490]

APS no longer has the max requirement based on your highest demand charge, or on your service panel size. I don't know why they still have that information in their interconnect agreement. After sending emails to them they said the ACC had them remove that limitation. They said the only limits are what the AHJ allows likely NEC rules 120% max current of your panel busbar. The problem is APS requires you to only buy off the California Energy Commission list of approved equipment. The few batteries that are listed are very expensive although as of November EG4 got their pro-power battery approved. The EG4 18PKV and a Propower battery are both approved by the CEC. APS also requires you to install meter(S) they require a meter between your panel and inverter so they can monitor how much power you're using. California wanted to charge solar customers an 8% tax for power generated at their own home. They gave up on that idea although I bet APS would love that.