CEO and founder of U.S. Nikola Trevor Milton attends a news conference held to presents its new full-electric and hydrogen fuel-cell battery trucks in partnership with U.S. Nikola, at an event in Turin, Italy, December 3, 2019. REUTERS/Massimo Pinca
Nikola founder Trevor Milton is now worth $7.1bn after shares of his hydrogen-powered electric truck company more than doubled following their stock market debut. Photo: Reuters  

How hydrogen is becoming the next big clean energy source