Scurrying around the Lowestoft shipyard in hard hat and leather jacket, Kelly becomes serious as he recollects the countless lessons he has learned over the past decade about bringing an idea for creating renewable energy to fruition. The most important lesson is to remain realistic: empty promises are the one thing investors and employees will never forgive. "You have to be very careful about the timescale you set for yourself and your company, and you need to be painfully realistic about your finances," he says.