This cost, evaluated over the 20-year lifetime assigned to each case ship, is made up of capital and operational expenditure (CAPEX and OPEX) and fuel expenditure, the most significant variable. The project uses the concept of total cost of ownership for all assessed fuel and technology options with defined fuel price paths. Electrofuels (e-fuels) are synthesized by chemically combining “green” hydrogen – from electrolysing water with renewable power – with carbon dioxide from the air or captured from a source such as industrial flue gas. Blue fuels are produced via reformed natural gas with carbon capture and storage (CCS). The project involves complex modelling and analysis of the financial feasibility of fuel and technology options, including less well-known fuels such as blue fuels, e-fuels and biofuels. For example, an ammonia-fuelled tanker must be bunkered more frequently than a traditional very low sulphur fuel oil (VLSFO) tanker of today, provided tank dimensions are the same. Calculating average yearly fuel consumption for both case ships means they can be compared across different fuel storage capacities, which vary depending on how long owners need them to operate between bunkering. The hulls for the MR and LR2 concepts are optimized to consume about 10% to 15% less fuel on average than existing vessels delivered during 2015–2017 with similar main dimensions and operational profiles to the case ships. The study factors in speed distribution, propulsion requirements, main-engine fuel consumption/specific fuel oil consumption (SFOC), energy losses, engine maker’s tolerance and other fuel characteristics. Fuel consumption for the MR and the LR2 is based on simulating the case ships’ operating profiles as if they were in Minerva Marine’s fleet and built to Deltamarin’s designs. The project’s report discusses other practical considerations – such as class and regulatory requirements – but only qualitatively. The case ship concepts were defined primarily to focus on quantifying fuel consumption and fuel tank requirements.