For video interview they ask you ask why fairheat? why engineering? why you're ideal candidate? Then you're asked to solve questions/calculations on an energy system (Not too difficult) try and explain your thought process. Then for the in-person interview, the technical questions are more difficult so do your revision on thermodynamics and heat transfer. They also try to gauge your personality by asking standard STAR questions. Overall good experience. The only downside is if you don't get the job they don't get back to you till like 3 or 4 weeks later. But if you do you'll hear back from the the very next day or at most 2 days after