Story at a glance

  • America’s infrastructure is aging, and climate change is exposing its weaknesses.
  • Decentralizing power grids could help make them more reliable and resilient.

Climate change is coming for America’s decaying infrastructure. Power grids have emerged as particularly brittle in the face of stronger hurricanes, flooding and longer, more destructive fire seasons. Weather related blackouts have doubled since 2003.

After Hurricane Maria, Puerto Rico was plunged into the second largest blackout ever recorded. Recently, the ravages of climate change fueled wildfires that have exposed the frailty of California’s electrical grid and prompted the state’s largest utility company to cut power, leaving nearly 3 million in the dark as nearby fires blazed. 

These broken systems have many searching for ways to make them more resistant to climate-driven threats that are becoming increasingly commonplace. Some fixes are just about beefing up the grid — like making sure it can handle the fierce winds of increasingly common Category 5 hurricanes or burying power lines underground in places with extreme fire danger. 

But while hardening power grids might make them stronger, it may not help them become more resilient. One strategy being discussed is decentralizing power grids, which means is making them smaller and more local. Some think this could prepare places like California for the slings and arrows of climate change while setting the table for increased use of renewable energy, Vox reports

Typically, a power grid is like a giant octopus, with a power plant generating huge amounts of electricity in the center, and tentacles of high-voltage transmission lines sending that electricity long distances to cities and towns where its voltage will be stepped down by transformers for local distribution.

The problem with this system isn’t hard to imagine: if a transmission line goes down or if a utility provider is worried about its power lines sparking fires then everything downstream of the problem loses electricity. 

But in a decentralized or distributed power grid, the octopuses get smaller and more numerous, which can help keep local problems local and gives utility providers a more nuanced ability to manage risks like fire. Getting rid of super-long transmission lines can also save utility companies money while making grids more reliable and less accident prone. 

The extreme end of the distributed energy spectrum is what we tend to think of as going “off the grid,” meaning a household or building supplies its own energy without any need for a utility provider. But really any system that can cut itself off from the centralized grid and maintain power is what’s called a microgrid. 

Energy storage is crucial to microgrids, and that’s part of what allows them to facilitate adding more sources of renewable energy to a region’s mix of power sources. The importance of batteries is that many renewables are intermittent, and having a store of electricity for when the sun’s not shining or the wind won’t blow smooths out the bumps in supply and surges in demand. Microgrids also aren’t all or nothing, they can be set up to accept power from a centralized grid and still be able to function independently if disaster strikes. 

Remote villages, military bases or industrial projects that run off generators are common examples of microgrids, but these days they’re increasingly moving from the frontier to the city where they’re used by data centers, university campuses and hospitals.

Puerto Rico plans to decentralize its power grid as it rebuilds its infrastructure after Hurricane Maria, and cities like Borrego Springs, California, and Fairfield, Connecticut, have already gotten the ball rolling with microgrids of their own. This is likely just the beginning, as a recent report projects microgrid installation will more than double between 2017 and 2022.

Published on Nov 08, 2019