Denmark must be climate neutral by 2050, which entails the replacement of fossil fuels with CO₂ neutral fuels. While the implementation of these technologies has an obvious benefit in reducing the emission of CO₂ to the atmosphere from the shipping industry, the possible derived environmental effects  of transitioning to CO₂ neutral fuels have not been examined. Potential  CO₂ neutral fuels for shipping are, among others, methanol, ethanol, biogas, bio-oil and  ammonia, each with its strengths and limitations.

The purpose of this project is to collect and summarize existing knowledge on CO₂ neutral fuels and their environmental chemical properties and to perform a theoretical environmental risk assessment based on the existing data in order to identify possible unintended environmental effects when using CO₂ neutral fuels.