Economic Effects of Sustainable Sanitation - SuSanA

Figure 13: Logistics system for urine reuse - system A (own contribution)
6.2.2.2 Costs of the urine logistics
Case Study Kampala
The costs of the logistics system have been calculated with the assistance of a Microsoft
Excel based model (cf. chapter 9.3). The model was exclusively developed for this purpose.
Various assumptions have been used in this model and different scenarios have been
calculated in order to simulate different system sizes (cf. Table 5).
The income for system A is generated through the marketing of the sanitised, liquid fertiliser -
human urine. A price for one litre of this fertiliser was calculated using the replacement cost
approach (cf. Drechsel, 2004). In this context, the price adds up to 0.01 EUR per litre. The
major input parameter in order to assess the scale of the system is the N demand of the farm.
The location of the farm was set to be 50 km outside Kampala, which was considered to be
the average distance from the city centre to the locations of large scale agricultural production
outside the city. The distance of the slums to the storage site is estimated to be 10 km.
The scenarios are calculated with a five year lifetime and the system is working at full
capacity in 10 000 l units 61 . A collection efficiency of 30% 62 is used for calculating the
amount of people being affected by the system, considering that many people are absent
during the day because of employments outside the area observed. The average volume of
61 The capacities of the individual components are: collection point tanks (10 000 l), tank trucks (10 000 l) and
storage tanks (24 000 l). Since a major share of the total costs is contributed by the transport costs and one truck
has the capacity of 10 000 l this volume is used as reference value or unit for the workload.
62 The collection efficiency of 30% is an assumption.
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