Optimum integration of polygeneration in the food industry

Due to its significant and simulta-neous demand for process-heat, electricity and cooling, the food and drink industry is especially suitable for polygeneration. The work of the project comprised efforts covering everything from surveys of current utilisation of poly-generation to estimating the potential use in the future as well as evaluating the obstacles for further devel-opment. Moreover, the project did also have the aim to aid future implementations by developing and dis-seminating tools for faster evaluation of food plants applicability for polygeneration. These tools comprise technical guidelines, a web-based feasibility calculator as well as training materials for consultants and educa-tors. All these tools are made available for interested bodies on the project website www.optipolygen.org . The results of the project reveal that whether polygeneration is applicable or not at a specific site is a complex question and depends on many details that may vary significantly by the local circumstances of each plant. Thus in order to be able to estimate the potential a thorough investigation of each plant site has to be undertaken comprising several issues such as: availability of local energy infrastructure, fuels, rules of electricity trade and transmission, district heat trade and transmission, carbon dioxide tax, regulations concerning biodegradable waste handling, subsidies, etc.. However, by disregarding these local differences and by instead extrapolating available technical and statistical data, the current potential for polygeneration in EU-15 food and drink industry is estimated to amount to 73,1 TWhel/year. The largest potentials are estimated to be in the meat and fish industry followed by the beer and dairy industry. There is no statistical data available on the current use of polygeneration in EU15 today, however considering the large potentials estimated in this project, it is fair to assume that these potentials are far from utilized. The main reason for this is most likely lack of awareness and knowledge at the current plants, but in some cases also due to technical barriers of the current commercially available polygeneration technologies. E.g. several of the commercially available co- and tri-generation technologies are only efficiently usable in the size range exceeding 100 kWel which therefore sets a technical barrier for smaller food plants. Especially high efficient small scale absorption coolers would significantly increase the potential for polygeneration. There is also a request for efficient fuel independent co-generation technologies in this size range, which would allow the use of solid biomass and solid residue from the food plant