Choice of the Optimal Design and Operation of Multi-Energy Conversion Systems in a Prosecco Wine Cellar

Despite the high energy consumption of wine making processes, little efforts have been spent so far, both at the industrial and scientific level, to search for alternative energy systems in wine cellars. In fact, almost all the existing cellars take electricity from the grid and burn natural gas or other fossil fuels to fulfil their energy demands. This paper analyses the energy demands of a real Prosecco wine cellar in the North East of Italy, which can be considered as a "reference" cellar for dimensions and wine production. The goal is to find the best energy conversion system in terms of maximum profits, efficiency and share of renewable energy utilization. Four alternative design configurations are proposed, and each one optimized considering the three objectives. Results show that a 35% gain in the maximum profits is obtained by including a natural gas fueled CHP internal combustion engine and an absorption chiller. This configuration is also the best one to achieve the maximum efficiency (61%), resulting in 18% reduction of primary energy consumption. Conversely, the utilization of a biomass boiler and an absorption chiller allows maximizing the share of renewable energy consumption, which is about 35% considering the existing availability of biomass from pruning harvesting and the relative limited surface available for photovoltaic generation. This option may become economically interesting when the price of natural gas increases of at least 50%.