Very easy. I had no experience in PV design or solar but a lot of work and research experience. Make sure to be able to speak about how you can apply your past experience and learned skills to this position. They want someone who is diligent, detail-oriented, EFFICIENT, preferably laid-back (I've heard my team lead speak about a past interviewee being too uptight), does not mind working at nights or weekends, goal-oriented etc. Two interviews over the phone. That's all.

There was a test. But it was mainly to test the candidate's thinking process. Then there was the typical interview question session. It was pretty simple. Just review interview questions and you'll be fine.