It was very chill and lax in the beginning. Recruiter eased me into the interview. Technical questions were somewhat challenging towards the end. They expect you to know quite a bit about PV systems.

I met a connection for lunch one day outside of the interview process. A couple weeks later, he offered to help me get an internship at Tesla. The interview process was fairly low stress, but note that this was in 2012. I talked to several members of the battery engineering team, one at a time. Each interviewer had a different role in the team.