How to reduce MV collector system cost in solar, wind and BESS projects
In many utility-scale renewable energy projects, the MV collector system design still follows a familiar pattern.
- Loop configurations.
- RMU-based layouts.
- Cables routed through every station.
These approaches are proven and widely used. But as projects continue to scale, they also introduce higher costs, longer lead times and more installation effort than may be required.
Are we designing collector systems based on what is needed, or simply based on what is standard?
Where conventional collector systems create inefficiency
Traditional loop-in / loop-out configurations and RMU-based collector systems provide control and flexibility. At the same time, they typically route the cable through every station, increasing the number of terminations, cable length and required infrastructure.
At smaller scale, this is manageable. At utility scale, these repetitions start to impact cost, installation effort and coordination effort.
Not because the concept is wrong.
But because it is applied everywhere, even where it may not add value.
A different way to approach MV cable routing
One way to reduce collector system cost is by simplifying how and where connections are made.
In many collector systems, two functions are combined at every point:
- Connecting assets
- Providing switching and protection
In practice, these do not always need to happen at the same location.
By using branch splices as a temporary or permanent alternative to switchgear, connections can be made directly on the main feeder without routing the cable through every station. This allows switching and protection to remain where they are functionally required, while simplifying the overall cable layout.
The result is a more direct routing of cables, with fewer components and less infrastructure across the site.
The exact impact depends on the project layout and how protection is coordinated across the network.
What this means for project performance
Changes in MV collector system design translate directly into how a project is executed.
A simplified layout can influence:
- Total cable installed across the site
- Number of terminations and interfaces
- Trenching and civil scope
- Installation time and coordination
These factors are closely linked to both CAPEX and project timelines. As a result, collector system design becomes a project-level decision, not just an engineering one.
Why scale makes the difference
The impact becomes more visible as projects grow.
In solar, wind and BESS projects, layouts are repeated over larger distances or across multiple phases.
Small design choices are repeated again and again, and that is where they start to impact overall project cost and execution.
Rethinking simplicity and control
Simplifying a collector system architecture does not mean reducing control.
Switching and protection remain essential, but they do not need to be present at every connection point. By separating connection from switching, it becomes possible to reduce complexity while maintaining how the network operates in practice.
How this works in detail depends on system design choices, protection philosophy and application type.
Want to explore this further?
This blog introduces the principles behind optimizing MV collector systems. It does not explain how these choices are applied in practice.
The full engineering guide provides more insight into:
- Different collector system architectures and how they compare
- Where simplification is technically viable and where it is not
- Application in solar, wind and BESS projects
- Engineering considerations such as protection and cable sizing
