Fordonsgas ur gödsel och vall
AbstractThe dependency of fossil fuels in the transport sector causes large emissions of carbondioxide. This problem can we reduce by using vehicle gas from digested solid manure and leftover of pasture. I have studied the potential for this in the county of Västernorrland. Thepurpose is to investigate how much vehicle gas that can be extracted.One central, large scale digestion and upgrade plant should be placed in Härnösand. Theamount of pasture and manure that is economical and practical available is enough to produce2,7-3,5 millions Nm3 vehicle gas. It corresponds to 1 800- 2 400 cars, each driving 17 860 kmper year.The heating value of the vehicle gas is 26-34 GWh. To extract this energy you have to supplyenergy corresponding to a heating value of 4,9 GWh for transport of raw material anddigested sludge together with 13-14 GWh for process heat and electricity.If the gas replaces petrol the emissions from the lifecycle of the fuel decrease with 5 600-7400 ton CO2-equivalents. The emissions by the vehicle decreases with 640-840 kg NOx, theemissions of hydrocarbon increases with 60-80 kg and the emissions of particles remains thesame.The increased content of easy available nitrogen is about 40 tons, it can replace about 5 % ofthe nitrogen supplied as synthetic fertilizer. The contribution to the nitrogen resource bydigested sludge is greater than its contribution to the supply of fuel.The cost for the gas is 12-14 kr per petrol equivalent, that is little more than the today?s priceof petrol of 11,28-12,24 kr. Above all, it is the cost of transport that cause the high cost.