The Possible Role of Large-Scale Sewage Plants in Local Transport

Large-scale sewage plants in large cities are suitable for the production of large quantities of biogas, using economically viable biogas upgrading technologies and generally available public transport fleets of a sufficient number of local buses, as well as municipal vehicles. The conditions for the sale of locally produced CNGs do not depend on gas suppliers, they can be very well integrated with local waste management, and the local emission reductions occur in the inner city, where air pollution is the most serious problem. At the same time, the cogeneration solution currently of decisive importance for wastewater plants is more economically and environmentally advantageous in the production of biomethane. The consumption of heat and electricity by these plants is significant and must be supplied through the purchase of biomethane. However, for the local authority, when converting diesel buses, compressed biomethane (CBM) offers much greater savings, so at the municipal level, the process is economically profitable. The short-term spread of CBM (due to the small number of filling stations) is bound to local systems. If more and more cities operated a similar system (allowing refuelling within a few dozen kilometres), it would be expected that passenger cars would also be more widespread.