DC vs AC Coupled Battery Storage Systems
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Minimum Conversion Points = Reduced Electricity Waste
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Single inverter reduces system complexity
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PV and Battery system are "behind-the-meter" simplifying utility interconnection
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Faster battery re-charging compared to AC system during extended outages
DC-Coupled System
Stores DC current electricity in Battery converts DC to AC to serve home load
Generates DC current electricity
DC-Coupled System
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Multiple conversion points = Wasted Electricity
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Multiple inverters require more system equipment and communication points, creates increased system failure rate
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PV system size constrained by utility regulations
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The charge rate is slower compared to DC system when grid outage occurs
AC-Coupled System
Generates DC current electricity
Converts DC current to AC current
Converts AC to DC and Stores DC current electricity converts back to AC to use stored electricity