My advice to all students is to question everything! You never know where a "silly question" may lead you. - Derek Abbott

My starting point is as an academic who always thought nuclear was the answer, but who then looked at the figures and came to an inescapable conclusion that solar-hydrogen is the long-term future. I did not come at this as a green evangelist. I am a reluctant convert.

The fact that there simply is 5,000 times more sun power than our consumption needs makes me very optimistic. It's a fantastic resource. We have the ingenuity to send man to the moon, so we definitively have the ingenuity to tap the sun's resources.

My advice to prospective PhD students is to follow your passion and pick a topic that interests you — don't do a PhD topic that you hate, but you think will be lucrative. Because the big picture is that it is the fundamentals learned and problem solving skills gained from your PhD that will open the real career doors. Topics come in and out of fashion — it is the investment in yourself and the person you become through your PhD experience that really matters in the end. Of course, if you happen to love a topic that turns out lucrative then great — but this is hard to predict.