Development of an ICE-Based Micro-CHP System Based on a Stirling Engine; Methodology for a Comparative Study of its Performance and Sensitivity Analysis in Recreational Sailing Boats in Different European Climates

Abstract

Micro combined heating and power (micro-CHP) systems are becoming more than important, and even essential, if we pretend to take full advantage of available energy. The efficiency of this kind of systems reaches 90% and important savings in energy transport processes can occur. In this research, an internal combustion engine (ICE)-based micro-CHP system was developed and tested under specific constraints. The system uses a two cylinder Otto engine as prime mover, coupled to an electrical alternator, and it uses exhaust gases and engine cooling circuit heat. The micro-CHP system was developed to match the electrical power of a typical Stirling engine (SE)-based micro-CHP unit, in order to later compare both systems' performance under similar circumstances. Different operating modes were tested under different engine speeds, in order to find the optimum operating point. A stand-alone portable application of this system was performed using recreational sailing boats as mobile homes. Specific considerations had to be taken, related to boundary conditions with sea water, and a transient simulation was performed, considering the boat under three different European climates. Results were compared for the different locations and the performance of the equipment shown. A comparative study with the SE-based micro-CHP system performance was done, and a sensitivity analysis of the influence of the battery size was carried out under the same conditions. The SE and ICE-based proposed micro-CHP system have similar behavior, except for the differences found due to the electric/thermal power ratios in both systems. Battery bank size sensitivity analysis reflects a limit in performance improvement. This limit is caused by the uniform distribution of electrical demand profile.

Control strategy optimization of a Stirling based residential hybrid system through multi-objective optimization

“…The simulation of the installation was carried out using the commercial software TRNSYS. This is a simulation program for transient systems, which has been widely used and proven effective for the modelling of cogeneration facilities, both in the field of research and engineering [38][39][40].…”

Simulation of Polygeneration Systems

“…Polygeneration systems based on the coupling of CHP and solar energy systems may be used in a plurality of applications. As an example, Rey et al [33] developed a micro CHP system to be used in recreational sailing boats used as mobile homes; these users are not considered much in literature, but they are very sensitive to solutions able to improve their self-sufficiency. They designed, built and tested, in different European Climates, a micro-CHP system devoted to recreational sailing boats.…”

Experimental investigation of dairy biogas as fuel for a molten carbonate fuel cell

“…Energy policy takes into consideration micro cogeneration as an element of a more effective use of electric energy from the electric power network, 7 as illustrated by the example of households for which biofuel is more suitable than compressed hydrogen 8,9 . Office buildings 10,11 are potential distributed generation sources, as they are already equipped with emergency units (mainly internal combustion piston engines 12 ), and connected to the municipal networks 13 (natural gas, electricity, heating) 14 . The building sector uses about 40% of total primary energy and contributes to 35% of global greenhouse gas emission 15 .…”