Nolan Pelletier for Business Insider
For decades, electricity has flowed one way: from power producers to public utilities, which then distribute it over vast distances to households and businesses. That utility-to-consumer status quo, however, is getting challenged. A growing number of Americans have started generating electricity from solar panels installed at their homes. And new technologies and a fleet of startups are allowing people to not only independently power their homes but also store and sell excess solar power to their neighbors.