At the present, commercial conversion technologies producing energy in small-scale are the most suitable for the Northern Periphery. Also an inexpensive and simple construction is an advantage. Occasionally, plants with capacities of few MW can be defined as small-scale but these plants are industrial sized and inhabitants of rural areas might oppose the plants. Gasification and anaerobic digestion are, in general, the most suitable technologies for northern periphery conditions. Anaerobic digestion is an excellent technology to produce energy from wastes also in very small scale while gasification is maybe a slightly more demanding technology in small-scale with special feedstock requirements. Anaerobic digestion is a fully commercial technology and is suited well to energy production from biomass-based wastes. The produced biogas can be utilised as transportation fuel or via heat and power production.
Gasification has long been a commercial technology but the number of gasification plants in operation is currently rather low. However, there are now numerous providers of small scale gasification plants. The product gas can be used to combined heat and power production or as transportation fuel in special vehicles, or it can be processed further to liquid transportation fuels.
Combustion is an ancient and very common technology for heat production purposes but not effective to generate electricity in small scale. Fuels cannot be produced from biomass through direct combustion either.
Pyrolysis is expected to be commercial in large-scale, but there are challenges. The product, pyrolysis oil, is demanding to upgrade to the quality of transport fuel. The oil can be used for combined heat and power production but the overall efficiency of the pyrolysis process is rather low.
Fermentation from first-generation raw materials is a commercial technology but competes with food production. Second-generation fermentation from wood and herbaceous raw material starts to be commercial technology in large-scale. The produced alcohol can be used for heat and power production and preferably as transportation fuel.
References
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