At the Copenhagen test site, Sørensen's team is experimenting with different carbon-neutral and carbon-free fuels to see how effective they can be at generating the immense horsepower necessary to move container ships and bulk carriers across the world's oceans.The upcoming COP27 gathering in Sharm El-Sheikh, Egypt, which runs Nov. 6 to 18, is expected to zero in on the decarbonizing challenges facing the shipping industry far more prominently than in the past."I think what we need to see now is the IMO revise that target to full decarbonization [by 2050]," said Ingrid Sidenvall Jegou, with the Global Maritime Forum, a non-profit group that's attempting to steer industry players and international regulations toward hitting net-zero.Alan McKinnon, professor of logistics at Kuehne Logistics University in Hamburg, Germany, says resistance has come from smaller nations, such as Panama, with an outsized dependence on shipping and concerns about the economic consequences of a carbon tax.The European Union has decided not to wait for the IMO to make a decision and has announced that starting next year, ships calling at European ports will have to begin paying into the bloc's emissions trading scheme, which serves the same function as a carbon tax."