Design of a mini combined heat and power cycle for naval applications

The themes of energy conversion with low environmental impact and energy recovery, will have, in the near future, a high potential for development for naval applications. The containment of pollutant emissions can be achieved by an innovative mini gas-steam combined cycle with thermal energy cogeneration to feed the ship thermal utilities, in place of or alongside the electric diesel engines currently used. The present work is focused on the definition of the architecture of the system, by selecting optimal thermodynamic cycle parameters and power repartition, as well as on the choice and sizing of the individual components to obtain a compact and high efficiency system. The proposed basic mini-cycle consists of a gas turbine of about 1.5 MW and a steam turbine of about 0.5 MW. For an overall electrical efficiency of about 28%, a total return (thermal + electricity) of 75% can been achieved. An example of plant providing larger power, in a partially modular arrangement is also proposed.