At last month’s MariNH3 conference in Nottingham, a series of keynotes laid out the opportunities and challenges ahead for marine ammonia fuel. Onboard ammonia cracking technologies are moving through testing phases and closer to commercialisation, vessel designers are working through the unique challenges of carrying ammonia fuel onboard, and emissions mitigation technology (in combination with adherence to existing Tier 3 standards) will be necessary to ensure that ammonia-powered vessels are more environmentally-friendly than conventional counterparts.