Ex. grid tied PV system, wanting to add stand by generator and battery bank UPS

[Manny Renteria]

Hi all,

I need help designing a unique Hybrid UPS system.

Current System Details:
Electrical- 400 amp split system (150 & 100 Ampo mains + 60Am solar backfeed)
Solar - 9.156 KwDC (28 SPR-327 NE-Wht-D modules with 1 SPR-10001f-UNI inverter)

My customer would like to install a stand by generator to charge a battery bank that will in turn power his loads once the generator has completed the charge and powered his loads simultaneously during the day.

What products and/or methods can be suggested to get optimal use of all three systems?

 

[jaggedben]

Manufacturers that make products in this category include SMA (the Sunny Island), Outback, Schneider (Xantrex), and Magnum.

You'd be using one of two approaches:

1) Reconfigure the solar system for use with DC coupled offgrid inverters (you'll probably need more than one to utilize all the solar). This will probably involve substantial modifications to the array wiring.
2) Install new inverter/chargers and couple the existing system to it via the AC wiring. This may avoid lots of array reconfiguring, but require more expensive inverter equipment.

Either way, because you've got a fairly large existing system, you will probably not be able to use the existing inverter, even with AC coupling. (BTW that existing inverter appears to be a re-branded Power One model.)

You have a lot of studying to do. For starters, I recommend reading this article on AC coupling.:
https://solarprofessional.com/artic...upling-in-utility-interactive-and-stand-alone

This kind of project is not for the faint of heart or those with shallow pockets. Unless this customer experiences frequent power outages, or just wants to do it no matter the cost, it may not be worth it to include the solar in the backup generation plans. The simple alternative would be to install a transfer switch for the generator where the solar is connected to the utility side.

 

[ggunn]

This kind of project is not for the faint of heart or those with shallow pockets. Unless this customer experiences frequent power outages, or just wants to do it no matter the cost, it may not be worth it to include the solar in the backup generation plans. The simple alternative would be to install a transfer switch for the generator where the solar is connected to the utility side.

I agree. Unless the grid is frequently out for extended periods of time, it makes no sense to have the PV active when the grid is down.