The client, located in the province of Mantua, Lombardy, Italy is a livestock farm specializing in pigs, which has decided to acquire a biogas production system fueled by the fermentation of the sewage created by its 10,000-odd pigs.
The biogas produced in the fermenting tanks is used as fuel for a micro power plant based on a 637-kW engine by the german firm, Jenbacher. Said plant takes advantage of the favorable all-comprehensive tariff the Italian government grants to new small power plants powered by renewable energy sources.
The system used for heat recovery is a ZE-50-ULH low temperature Organic Rankine-cycle module which produces 50 kWE of electricity by recovering waste heat from flue gases and cooling jackets of the forementioned Jenbacher engine, thus contributing significantly to the overall system efficiency and productivity.
The ORC module used in this plant is entirely contained in a custom container, located outdoors, which is both compact (4,2 x 1,5 x h 3,1m) and totally weatherproof. This container hosts the whole ORC system, including turbine, secondary heat excangers and control panel, as well as a climatization system for the control panels. Cooling for the condensation part of the cycle is ensured by an EvapCo cooling tower located beside the container.
The fuel used by the Jenbacher engine (biogas) is an environment-friendly and renewable energy source made competitive by state and regional incentives. It is also CO2-neutral, as burning biogas releases in the atmosphere the same quantity of CO2 that was once captured by the plants that went to feed the animals.