On a tributary of the Hudson River, a tugboat powered by ammonia eased away from the shipyard dock and sailed for the first time to show how the maritime industry can slash planet-warming carbon dioxide emissions. The tugboat used to run on diesel fuel. The New York-based startup company Amogy bought the 67-year-old ship to switch it to cleanly-made ammonia, a new, carbon-free fuel. The tugboat’s first sail on Sunday night is a milestone in a race to develop zero-emissions propulsion using renewable fuel. Emissions from shipping have increased over the last decade — to about 3% of the global total according to the United Nations — as vessels have gotten much bigger, delivering more cargo per trip and using immense amounts of fuel oil. CEO Seonghoon Woo said he launched Amogy with three friends to help the world solve a huge, pressing concern: This backbone of the global economy has not started to transition to clean energy yet. “Without solving the problem, it’s not going to be possible to make the planet sustainable,” he said. “I don’t think this is the problem of the next generation. This is a really big problem for our generation.” The friends met while studying at the Massachusetts Institute of Technology. In their free time during the COVID-19 pandemic, they brainstormed how to power heavy industries cleanly. They launched their startup in November 2020 in a small space at the Brooklyn Navy Yard. The name Amogy comes from combining the words ammonia and energy. They looked for a boat and found the tug in the Feeney Shipyard in Kingston, New York, languishing without a mission. It could break ice, but little to no ice has formed on that part of the Hudson River in recent years, so it was available for sale. “It represents how serious the problem is when it comes to climate change,” Woo said. The project, he said, is “not just demonstrating our technology, it’s really going to be telling the story to the world that we have to fix this problem sooner than later.” They named the tugboat NH3 Kraken, after the chemical formula for ammonia and their method of “cracking” it into hydrogen and nitrogen. Amogy uses its ammonia in a fuel cell, making the tug an electric-powered ship. The International Maritime Organization set a target for international shipping to reach net-zero greenhouse gas emissions by, or close to, 2050. Shipping needs to cut emissions rapidly and there are no solutions widely available today to fully decarbonize deep-sea shipping, according to the Global Maritime Forum, a nonprofit that works closely with the industry. There is a lot of interest in ammonia as an alternative fuel because the molecule doesn’t contain carbon, said Jesse Fahnestock, who leads the forum’s decarbonization work. Ammonia is widely used for fertilizer, so there is already infrastructure in place for handling and transporting it. Ton for ton, it can hold more energy than hydrogen, and it can be stored and distributed more easily. “It certainly has the potential to be a main or even the main fuel,” Fahnestock said. “It has a potentially very friendly greenhouse gas footprint.” Ammonia does have drawbacks. It’s toxic. Nearly all of it currently is made from natural gas in a process that is harmful for the climate. And burning […]