Procuring a megawatt or megavolt-ampere test platform is often approached as primarily a cost decision, but cost is the part that's easiest to get right. What tends to matter more — flexibility of deployment, space utilisation and power density, and whether the system can scale further without a complete rebuild — is harder to evaluate from a spec sheet alone.
Why MW/MVA Platforms Are a Strategic Decision, Not Just a Power Spec
Utility-scale renewable energy systems typically run in the 2.5–3.45MW range today, with central inverters increasingly heading beyond 5MW. The shift toward weak grids requires MW-scale grid-forming inverters to provide short-circuit current support, placing genuinely higher transient demands on the test platform than steady-state power delivery alone.
Building to 6MVA with a Module-Based Cabinet System
A grid simulator built on a module-based cabinet platform — such as ActionPower's NEXUS AC programmable power supply — offers scalability both within the cabinet and between cabinets via parallel connection.
Starting point. A single cabinet can reach up to 400kVA, or be extended for a master-slave configuration reaching 750kVA — enough for a complete bidirectional AC source/load test bench for early functional validation.
Scaling via parallel connection. With up to eight cabinets paralleled, 400kVA single cabinets scale linearly to roughly 3.2MVA, and 750kVA master-slave cabinets scale to roughly 6MVA.
Floor space. A full 6MVA, eight-cabinet platform occupies roughly 11.2 square metres, working out to a power density in the range of 357–536 kVA per square metre — a compact footprint achieved by avoiding the parallel-complexity penalty of large numbers of small rackmount units.
Reaching 10MVA with Tower-Type Architecture
A 6MVA module-based platform comfortably covers most central PV inverters and MW-scale BESS testing. But emerging assets — 10–15MW offshore wind turbines, large central inverters — push past what a 6MVA platform can deliver. ActionPower's TITAN Grid Simulator addresses this beyond-6MVA tier: single cabinets covering 350kVA to 1MVA, scaling via parallel connection to a 10MVA maximum.
Module-Based Cabinet vs Tower-Type at MVA Scale
Footprint at equal power levels favours module-based cabinets. Module-based cabinets achieve higher system-level density through optimised multi-cabinet layouts, while tower-type systems excel in single-unit density instead.
Scaling granularity favours module-based cabinets, ultimate single-unit density favours tower-type.
Physical loading differs meaningfully. A module-based cabinet typically distributes weight across a smaller footprint with lower weight-per-area than an equivalent tower-type unit, which concentrates significant mass into a single point load — a real structural engineering question for upper-floor deployment.
Decision Framework
| Consideration | Favours module-based cabinet | Favours tower-type |
|---|---|---|
| Final power level | Uncertain, expected to grow step-by-step | Already known to be very high (beyond 6MVA) |
| Floor space | Limited, need higher density per area | Available, dedicated test floor |
| Floor loading | Ground floor or reinforced floor | Verify point-load capacity carefully if upper floor |
| Power ceiling | Up to roughly 6MVA practical | Beyond 6MVA, up to 10MVA |
A Practical Recommendation
Treat the decision as inseparable from a genuine structural engineering consultation — verify concentrated load capacity before any upper-floor deployment. For evolving power requirements, starting with a module-based cabinet system and planning a possible transition to tower-type only if requirements exceed it avoids overcommitting to either architecture early.