Commercial Switchboard Conversion and Future-Proofing for Battery Readiness – Optimising a Multi-Tenant Site (Part 3)
Converting a legacy commercial switchboard into a compliant embedded network is one of the most technically demanding steps in a multi-tenant energy upgrade. At this Charlestown facility, NGG re-diverted the original mains supply into two new embedded network switchboards, re-established downstream connections to the existing infrastructure, and installed a 630A isolator to support both the 442.5kW solar carport system and the 220kW / 450kWh battery storage system. Provisional connection spaces were also built in for future distributed energy resources. It’s a low-cost decision at installation that removes a potentially project-stopping constraint later.
Key Insights
A legacy main switchboard can be converted into a compliant embedded network without replacing the original infrastructure.
At this site, NGG re-diverted the mains supply into two new embedded network switchboards and reconnected sub-mains into the existing boards downstream of the main protection device.
Provisional switchboard connection spaces are a low-cost inclusion at installation and a costly problem if omitted.
Retrofitting them after commissioning typically requires a full switchboard module extension: expensive, complex, and potentially enough to make a future project commercially unviable.
Solar PV and battery storage can share a single PVDB when configured in parallel.
The 630A isolator at this site supports both assets via the same PVDB, reducing infrastructure complexity while maintaining full protection for each.
Converting a Legacy Switchboard into an Embedded Network
The Charlestown site had a single original main switchboard: two back-to-back panels operating as one unit. To establish a compliant embedded network, NGG re-diverted the mains supply cables feeding that original switchboard into two new embedded network main switchboards installed in the same room. Sub-mains were then reconnected into the original boards, downstream of the main isolator and protection devices.
This approach allowed the embedded network to be established without decommissioning the original infrastructure. The site’s existing electrical distribution was preserved while the new metering and control architecture required for an embedded network was layered in.
Embedded network conversions are subject to strict compliance requirements, covering switchboard provisions, physical space allocation, and protection coordination. Non-compliant conversions carry consequences that extend across every tenant connected to the network. Achieving a clean outcome here required careful planning of the cable routing, switchboard sequencing, and the physical arrangement of the new MSBs alongside the original.
Building Switchboard Capacity for Future Energy Assets
With the embedded network established, NGG installed a 630A isolator on the existing main switchboard to support both the solar PV system and the battery. The solar and battery assets connect to the same PVDB switchboard in parallel, reducing the number of switchboard interfaces required while maintaining clear separation between each asset.
The detail with the greatest long-term commercial significance, however, is what was left deliberately unoccupied. Below the active connections, NGG built in provisional spaces: spare connection points physically sized and positioned within the switchboard for future distributed energy resources. These are not reservations in a design document. They are real, accessible spaces ready to receive new circuits without structural modification to the board.
The alternative, returning to add a connection point after commissioning, typically requires extending the switchboard with an additional module. The cost and complexity of that work is material. In some cases it’s enough to make a future project unviable before the business case is even assessed. Incorporating that capacity upfront, while the switchboard is under construction, eliminates that barrier before it has a chance to form.
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Watch Next
Watch the earlier parts of this series to understand the commercial model and spatial engineering behind this site, or continue to the next video for further insights.
Optimising a Multi-tenant Site with Solar & Battery (Part 1)
Optimising a Multi-tenant Site (Part 2): Spatial Engineering & VPP Readiness
Optimising a Multi-Tenant Site (Part 4): Maximising Solar Carport Site Footprint
Optimising a Multi-tenant Site (Part 5): BESS Integration and the Revenue Loop
What is the 30in30 initiative?
This video is part of Next Green Group’s 30in30 initiative. We’ve committed to deploying 30 Megawatt-hours of behind-the-meter commercial & industrial (C&I) battery storage across Australia over the next 30 months. We’re opening our internal playbooks to show C&I leaders the engineering and financial reality, empowering them to navigate the energy transition confidently.
Next Green Group is a vertically integrated energy solutions provider delivering complete asset lifecycle management. With 14 years of industry experience and more than 15,000 energy projects delivered, we bridge the gap between behind-the-meter energy infrastructure and front-of-meter wholesale market dynamics through our retail energy arm, Next Business Energy. We engineer, construct, and provide ongoing operations and maintenance for commercial energy assets to strict ISO & Australian standards. Backed by global powerhouse Sojitz Corporation, we combine this technical execution expertise with structured financing solutions to remove capital barriers and ensure long-term commercial performance.