Stephen Crolius is the co-founder and president of Carbon Neutral Consulting, a New York-based sustainable business consultancy. He and his team recently released The Ammonia Report, an analysis of the prospects for using ammonia as a maritime fuel instead of heavy fuel oil, the petroleum-derived traditional source of maritime energy. So much of what we buy today is shipped halfway around the world. Sometimes, the components of a product are shipped from the U.S. to Asia, processed and then shipped back. Almost all of that shipping activity burns oil today, which accounts for about 1.8% of humanity's annual carbon footprint, according to the European Commission’s Climate Action office. We need to change the fuels used to power sea-going freight vessels to sustainable alternatives, and several are emerging. One of those is ammonia.Stephen previously served with the Clinton Foundation’s Climate Initiative and as president of the Ammonia Energy Association. Ammonia has been used in fertilizers since the early twentieth century, a development made possible by the emergence of the Haber-Bosch process for mass producing the chemical, which revolutionized farming. Now ammonia is coming into use as a fuel or an intermediate storage medium for energy that can be processed to yield pure hydrogen in fuel applications. You can follow the developing story of ammonia fuels at https://www.ammoniaenergy.org/articles/.