Are Minigrids the Answer to Puerto Rico’s Grid Woes?
A new 300-page strategic plan from the Puerto Rico Electric Power Authority (PREPA) suggests that “minigrids” are the key to bolstering the island’s troublesome power grid. The plan – called the Integrated Resource Plan (IRP) – calls for 8 self-sufficient minigrids or “zones of resiliency” to be connected to the main grid which could be activated or isolated from the grid during emergency situations.
How Minigrids Work
Minigrids would be connected to the main grid via transmission line. If a connecting transmission line is severely damaged and taken offline, the associated minigrid could be isolated to operate independently from the main grid, allowing residents in the served areas to keep the lights on.
The minigrids may also contain smaller microgrids in remote geographical areas that can be isolated from the minigrid within which it resides in order to provide an additional layer of resiliency to these rural areas.
Will It Solve Puerto Rico’s Problems?
This all sounds great in theory, but I’m not sure how practical it is. In order to accommodate 8 zones of resiliency, the island’s transmission and distribution system would need to be at least partially reconfigured, requiring a massive investment of time, money and resources. In addition, there is some ambiguity around certain rules and regulations such as microgrid development incentives, overlapping utility and municipality roles, and interconnection protocols.
Additionally, the IRP has not yet been formally approved for rollout. The island’s Energy Bureau will need to review the plan, and I doubt it will be approved as-is. That’s just generally not how things like this work. More likely is that the Bureau will require changes to the plan, a back-and-forth process that could take many months to complete.
The bottom line is that a network of minigrids should, in theory, help boost Puerto Rico’s resiliency and reliability, but it will be years before this vision can be realized.
