High-efficiency cogeneration systems for the food industry

The combined production of electricity and heat is a promising solution when energy inputs, whether fossil or renewable, are to be minimised and can be also economically rewarding if heat and electricity are produced through high efficiency processes. In this framework, featuring a large thermal and electric demand, the industry sector has seen widespread adoption of cogeneration systems to produce process heat/cool along with electricity. Among the variety of areas to be potentially conveniently matched to cogeneration applications, this study focuses on the food industry based on a collection of data derived from an extensive experimental campaign in a facility specialised in confectionery products and presently served by a combustion engine-based cogeneration unit. In the paper, a comparative analysis is conducted with the help of GateCycle software: CHP technologies based on gas turbine and steam power plant with both condensing and backpressure turbine are considered and properly designed as alternatives. The simulation of the energy flows allows for the estimate of specially defined performance indicators referring to relevant energy, economic and environmental quantities. Results display that, among the possible alternatives, the adoption of a 1.69 MW gas turbine-based cogeneration unit would perform better from an energy, environmental and economic perspective, given the favourable indicators it shows.