Ballard Power Product Development Engineer interview questions

After being initially contacted by HR, I had a ~45 minute phone interview with the HR rep and the hiring manager. This was a more general screening interview. For example, "Where do you see yourself in 5 years?" was one of the questions. Roughly a week later I was asked to come in for a technical interview. This started first thing in the morning, and I didn't leave until after 12. It was actually two separate consecutive interviews conducted with two pairs of interviewers. There was no break in between. I had to request a glass of water before the second interview started, as I had been speaking for almost two hours. These interviews focused more on the details of my resume, and a range of basic technical questions on engineering topics. (ex. "What does Poisson's Ratio represent? How will pressure change across this type of pipe feature? How would you determine the temperature profile across a wall made of multiple layered materials? How would you test for a statistical anomaly?) Although the questions were non-stop and the interview setup was fairly intense, all of my interviewers were easy to talk to, conducted the interview well, and I felt reasonably at ease. I felt that things had gone pretty well to this point. However, following this technical interview, Ballard failed to make contact with me again for several weeks. This is despite me calling the HR rep, leaving a message when she didn't answer, emailing her when I hadn't heard anything for ~1 week, and also leaving a voicemail for the hiring manager asking about the process, and informing them that I had received an offer from another company. It was a month after my technical interview, and 5-6 weeks after being initially called by Ballard, that I finally received an email from HR informing me that they had gone with another candidate. This is after six different people at the company had each invested a minimum of 1.5 hours each into reviewing me as a candidate. By the time they got back to me, I had already started work at another company which had initially contacted me after Ballard. I'm unsure that I would bother going for another interview with this company. It would be nice if they at least answered their phones.

It was a Technical Panel interview. There were friendly but the questions were though. it took about 1.5 hour and over 20 questions all relevant to job posting and my experience.