The Puerto Rico blackouts have provided some opportunities to test microgrids, or small-scale combinations of intermittent renewable energy with battery storage.

Broken transmission lines and utility poles have been repaired–at a painfully slow pace, though the majority of Puerto Ricans finally have power again–but the grid is still vulnerable (last week’s blackout followed another blackout two weeks ago). The next hurricane season is a little more than five weeks away. In the event of another storm, a network of microgrids could keep going even if the larger grid fails again…

Though the current microgrids are used at individual buildings, in theory, larger systems could support a whole community. Jonathan Marvel, a Brooklyn-based architect working with Resilient Puerto Rico, is talking to mayors about the possibility of microgrids that could provide power to 20,000 people.

Individual microgrids could also be linked together. In Arizona, Sonnen is adding solar and energy storage to thousands of new homes in a community to create a “virtual power plant” that can share energy between homes. When connected to the grid, the system helps stabilize the overall grid, but it can also operate if a disaster takes the larger grid out. Sonnen has done the same thing in Germany.