Two cost types define the viability of an investment - capital cost (CAPEX) and operational cost (OPEX). Due to the cryogenic nature of LNG and respective technologies, CAPEX is higher than for a ship using traditional fuel that is compliant with the emissions regulations. However, if compliance with emissions regulations cannot be guaranteed by the choice of fuel alone and exhaust treatment technologies need to be installed, the disadvantage in CAPEX is reduced for gas-fuelled ships.