01 · Engineering Review
Deployment challenge
Delivering storage, on-site generation, and charging infrastructure on an operating site, where the utility service, the existing distribution equipment, and the building systems were never designed to be coordinated.
02 · Engineering Review
System context
A modern integrated site is several systems sharing one point of common coupling: utility service, on-site generation, storage, controllable load, and a supervisory layer arbitrating between them. Each has its own vendor, its own commissioning process, and its own idea of who owns the boundary.
03 · Engineering Review
Key interfaces
- Utility service to site switchgear — metering, protection, and the disconnect requirement.
- Switchgear to storage and generation — protection coordination and fault contribution.
- Power systems to controls — telemetry, setpoints, and fallback behavior on comms loss.
- Controls to building and operations systems — who may curtail what, and under whose authority.
- Civil to electrical — conduit routing, pad locations, and access for maintenance and replacement.
04 · Engineering Review
Design and procurement considerations
- Specify the interface, not only the equipment. Protocol, point list, and failure behavior belong in the procurement documents.
- Confirm lead times against the utility milestone dates, not against the construction schedule.
- Require interoperability evidence before award, not a statement of intent.
- Design for the replacement cycle — the second battery installation is easier than the first only if the pad and conduit anticipated it.
05 · Engineering Review
Common failure points
- Protection coordination revisited after gear is ordered.
- Controls scope assumed to be included by three parties and delivered by none.
- Commissioning sequence that requires the site to be de-energized during operating hours.
- Telemetry that satisfies the vendor dashboard but not the utility's requirement.
- As-built documentation that does not survive the handoff to operations.
06 · Engineering Review
Project-stage checklist
- Concept — single-line drawn to the point of common coupling, with every interface named and assigned.
- Design — protection study complete and reviewed with the utility.
- Procurement — interface requirements written into every package.
- Construction — sequencing plan agreed with site operations, including outage windows.
- Commissioning — witness plan covering each interface, not each device.
- Handover — as-builts, point lists, and a documented operating envelope issued to the operating team.
07 · Engineering Review
Original diagram
One site, five interfaces
The boundaries where scope, protection, and controls responsibility change hands. Generic architecture — actual configurations are site-specific.
08 · Engineering Review
Questions for the delivery team
- Who owns each interface, by name, at each stage?
- What happens on loss of communications, and has it been witnessed?
- Which milestone dates are ours, and which belong to the utility?
- Can maintenance be performed without shutting down the operating site?
09 · Engineering Review
Related analysis
- Infrastructure Explained — microgrid control hierarchy
- Project Spotlight — how delivery roles are actually distributed