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Power Fundamentals

Breaker-and-a-half

Breaker-and-a-half is a high-reliability substation arrangement where three breakers serve two circuits. It is more costly and land-intensive than simpler layouts, but it supports maintenance and fault isolation without losing as much service continuity.

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Medium voltage

Medium voltage generally refers to distribution or facility-level voltages above low-voltage utilization levels but below high-voltage transmission. Exact thresholds vary by standard and utility, so Volterra should avoid treating one universal cutoff as definitive.

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Phase II ESA

Phase II Environmental Site Assessment uses sampling or testing to investigate potential contamination identified in Phase I or other diligence. It can affect purchase terms, remediation obligations, lender comfort, and development schedule.

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Black start

Black start is the ability of a generator or system to start without an outside electric supply and help restore the grid. It is mainly a grid restoration concept, but it matters for resilience discussions and some backup-generation narratives.

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