A customer inspects a Tesla Motors Inc. Powerwall unit inside a home in Monkton, Vt., in May 2016. Vermont’s largest electric utility, Green Mountain Power, in partnership with Tesla Energy, is offering 2,000 customers the chance to have a Powerwall in their home for $15 a month. You might not even know your lights are being kept on by the same chemical process that powers your smartphone, since the batteries could be tucked into what looks like a neighborhood junction box, or behind a fence in a substation. But now, thanks to efforts by startups and the utility companies they sell to (and sometimes battle), you might get one right inside your home. The rise of these home batteries isn’t just a product of our collective obsession with new tech. Their adoption is being driven by a powerful need, says Ravi Manghani, of GTM Research: renewable energy. Without batteries […]