Royal Dutch Shell, though still reliant on profits from fossil fuels, is investing more in renewable energy. Critics say the changes have to come quicker.
Charged via rooftop solar panels, the cells form a network that provides a building with backup electricity and that utilities can tap during peak periods.
After Hurricane Maria, battery companies like Tesla and Sonnen helped set up alternate power systems across the island. Now that the island is without power again, they are showing a way forward.
