Tesla is aiming to becoming an energy provider, not just seller of batteries. https://evannex.com/blogs/news/tesla-bids-to-become-a-giant-virtual-utility https:

Tesla is aiming to becoming an energy provider, not just seller of batteries. https://evannex.com/blogs/news/tesla-bids-to-become-a-giant-virtual-utility https://evannex.com/blogs/news/tesla-bids-to-become-a-giant-... is a decent intro. They would not be competing with PG&E (which has monopoly on power grid) but with companies that generate energy to PG&E e.g. the companies that burn coal or run gas peakers. Currently Tesla mostly sells batteries to such companies and they in turn make money selling energy to PG&E (for example PG&E instead of buying energy from a company using gas peakers to generate it, they would buy it from company that "cached" energy in a battery and is selling it to PG&E during peaks). It's a natural progression for Tesla to become such company themselves as they make the most costly part of running such business (i.e. battery). It'll take several years (there's regulation around this stuff and Tesla needs to learn the new business) but that's where they are heading.