Ask Mayfield Anything: AC Vs. DC Coupling

In this month's Ask Mayfield Anything session, Ryan Mayfield and Justine Sanchez outline the pros and cons of various solar+storage system architectures, focusing on AC- vs. DC-coupled systems.

[elwood_flip]

solid.. keep it up guys, love from San Diego Ca

[SnarkySolarGuy]

Outstanding! You covered these architectures very well. A growing industry needs to train its people as much as possible. Looking forward to the next AMA!

[ungrim]

I am surprised that it isn't every mentioned as a pro of an AC coupled design, but for me the main reason for going for the AC coupled system was improved load matching to PV output.

By monitoring the PV arrays power output I can dynamically adjust the load of the home to match the power use to minimise Grid usage. (Car charger, water heaters, hot tubs etc)

This isn't possible with a DC coupled system currently (unless the various systems share communication which is unusal unless they are made by the same company). As the storage and the array are both on the DC side they appear on the AC side as the same, as such battery storage often takes precidence over other dynamic loads until it is fully charged.

I personally very much needed to have the capacity to dynamically choose priorities of any of Car, Hot Water, Grid Feed in, and Battery. Which currently makes AC coupled the only viable option