TL;DR
Module mismatch is the production loss that occurs when solar panels wired in the same string differ in output — from manufacturing tolerance, partial shading, soiling, or mixing panel models — forcing the string down to its weakest member's current. Losses of a few percent are inherent in string systems, which is why expansions with different panels usually need a separate string or power electronics.
What it means
Module mismatch is the production loss that occurs when solar panels wired in the same string differ in output — from manufacturing tolerance, partial shading, soiling, or mixing panel models — forcing the string down to its weakest member's current. Losses of a few percent are inherent in string systems, which is why expansions with different panels usually need a separate string or power electronics. Microinverters and DC optimizers exist largely to eliminate this penalty by letting each panel run at its own maximum.
Where it sits in the glossary
Module mismatch is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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