Cruise emissions and economic feasibility of biofuels

•Shows that cruises emitted more than 45 Mt CO2 in 2019•Forecasts a business-as-usual scenario of 40 million passengers in 2030, causing 59 Mt CO2•For 2050 we estimate 145 million passengers, causing emissions of 71 Mt CO2.•A full replacement of the current fuel mix with biofuels raises the fuel cost ratio from 7 % to 18 %.•The profit ratio would fall from 15 % to 4 % when the current fuel mix is replaced by biofuel.•Concludes feed-in obligations for biofuels would reduce growth rates