Study and analysis of a cogeneration system with microturbines in a food farming of dry pasta

The Main purpose of this paper is to assess the possibility of installing a cogeneration plant in a food industry for dry pasta production. In particular, it was verified the feasibility of implementation of microturbines assembled in cluster, for a medium size cogeneration plant. This way it was seen that it is possible to combine the advantages in terms of the heat recovery at high temperatures of medium size turbines and of the greater flexibility of internal combustion engines. A preliminary analysis was carried out about the energy needs of the farm, mainly focusing on the thermal and electrical loads and the current methods of both energy supply and production. Several simulations were carried out for the preliminary design of the cogeneration plant, using suitable programming codes developed in Matlab and referring to the technical documentation for each machine used in the plant. It was shown that this plant allows for energy savings in all tested configurations. However, a good balance among various parameters leads to choose a size that is around the annual average value of the requested electric power (corresponding to 13 microturbines) or more. This is also confirmed by the analysis of the annual energy costs, which present a minimum in correspondence of the above chosen size. In addition to the energy and economic advantages, the system proposed in this paper also presents greater flexibility of use than that of individual engines and turbines. In fact, a peculiar characteristic of a cluster of microturbines is the possibility to efficiently meet the variability of the load and also to follow the expansion of the plant, gradually increasing the installed power. Therefore, the system studied in this paper shows that it is possible to use small machines, not only in the context of micro-cogeneration, but also in medium-sized applications, resulting advantageous in energy terms.