He did mention that the factory would rely heavily on solar for power. I expect Solar City will be announced as a partner. Also, Google is not so crazy, they have a sort of venture capital arm that invests in many clean-tech projects.
Have a look at these comments from Adam Jonas. What he describes happening for some investors is exactly what's been going on for me the past couple of weeks. There is a very real possibility that Tesla chooses to expand into a vastly larger opportunity than an EV company. Again, if all cars are to be EVs rather than ICE in coming decades... it will take a couple hundred of these giga factories.
We don't know if Tesla is going to decide to go from EV manufacturer to much larger opportunity in energy storage, but as Jonas points out it's like a call option we get holding shares in Tesla. I find his analogy to Amazon as to the expanding possibilities is well chosen.
Tesla Motors: The Next Amazon? - Stocks To Watch - Barrons.com
"Morgan Stanley’s Adam Jonas and team ask if Tesla is more than a car company:
Tesla’s plans for a ‘Giga’ battery factory starting to get more attention as a call option on the economics of mass produced batteries and the business model. We found the final sentence of Tesla’s prepared remarks on its plans to build the worlds’ largest lithium ion battery factory intriguing: “It is a massive, massive opportunity to push the cost curve down to levels people haven’t even dreamed of yet.” We find investors are starting to seriously ask if Tesla can be much more than just a car manufacturer. If this company can establish a technological and scale lead in every storage and infrastructure, might we one day look back at Tesla’s humble beginnings as a car maker much as Amazon (AMZN) began as a book seller?"