Calculating transport labour for organic waste from urban to rural areas

Three methods of calculating the transport labour required for transporting residual products from urban areas to arable land have been tested. The three methods were: (i) the method commonly used in practice today; (ii) a linear programming (LP) model, taking into account the maximum spreading dose of 11 substances; and (iii) a simplified LP model. The three methods were tested on the Uppsala region, Sweden. Two scenarios were analysed. The detailed LP model gave the lowest result with 65%, to 54% of the transport labour needed in today's method. The simplified LP model also gave lower transport labour, 74%, to 61% compared with today's method. The conclusion is that different methods of calculation can be used depending on the purpose of the calculations. If the aim is to get an estimate, the conventional method may be used. If the aim is to predict the real outcome if a new system is implemented the simplified model may be used. Finally, if the absolute minimum result is needed the LP model is the most appropriate.