Retrofitting Backup Power to a String Inverter System
Overview
The vast majority of grid tie PV systems are useless when grid failures occur. They shut down at the very time that the electricity generated on site is most needed. This does not need to be the case. There are a number of ways to ensure that a PV array does not become stranded during utility outages, the common thread between them all is that they utilize energy storage, additional inverters and a variety of different power electronics depending on the system design. It is also, in most cases, the most costly option.
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