CEO Elon Musk said Tesla will announce locations in "at least two" states where it could build the gigafactory, according to Bloomberg. He said, "What we're going to do is move forward with more than one state, at least two, all the way to breaking ground, just in case there's last-minute issues. The number one thing is we want to minimize the risk timing for the gigafactory to get up and running."
"We want to minimize the risk timing for the gigafactory to get up and running" – Elon Musk
This isn't to say that Tesla will actually build two gigafactories (at least, not yet, but Musk hinted there may come a day when the automaker will need a second one), just that it is going to make sure there is no hiccup in the supply of lower-cost battery packs for the upcoming lower-cost Tesla EV, sometimes referred to as the Model E. The gigafactory is expected to not only produce more li-ion cells than were made globally in 2013 but also to reduce the cost of the overall pack by 30 percent, setting the stage for the $35,000 Tesla EV (estimated) to appear.