Certain

Solar energy needs to be added when it exceeds a certain limit

The rule says that the total current on your main service panel's busbar — your home's electrical backbone — can't exceed 120% of its rated capacity. For example, if your panel has a 200A busbar with a 200A main breaker, the math limits you to just 32A of solar input. . TL;DR – There are actually two “120 % rules” in solar. Understanding this regulation is essential for anyone considering solar, especially when buying equipment internationally. Ever wondered why you can't just cover your entire roof with solar panels? There's actually a safety rule. . For all programs, the annual power output (kWh) of a PV system can be no greater than 120% of the total customer usage from the previous 12 months. Follow it, and you've got a. .

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