A Shell logo is seen at a gas station in Buenos Aires, Argentina, March 12, 2018. REUTERS/Marcos BrindicciRegister now for FREE unlimited access to Reuters.comRegisterSINGAPORE, April 21 (Reuters) – Royal Dutch Shell (RDSa.L) said on Wednesday it was conducting a feasibility study with partners to trial the use of hydrogen fuel cells for ships in Singapore, the first such move for the oil major.If successful, the trial will pave the way for cleaner, hydrogen-powered shipping, the company said, adding that its analysis points to hydrogen with fuel cells as the zero-emissions technology having the greatest potential to help the shipping sector achieve net-zero emissions by 2050.The trial will involve the development and installation of an auxiliary power unit fuel cell on an existing roll-on/roll-off vessel that transports goods, vehicles and equipment on lorries between Singapore and…