Tesla Is Plugging a Secret Mega-Battery Into the Texas Grid

Elon Musk is getting into the Texas power market, with previously unrevealed construction of a gigantic battery connected to an ailing electric grid that nearly collapsed last month. The move marks Tesla Inc.’s first major foray into the epicenter of the U.S. energy economy.

A Tesla subsidiary registered as Gambit Energy Storage LLC is quietly building a more than 100 megawatt energy storage project in Angleton, Texas, a town roughly 40 miles south of Houston. A battery that size could power about 20,000 homes on a hot summer day. Workers at the site kept equipment under cover and discouraged ...