5.5. Sensitivity analyses

Sensitivity analyses help in identifying the role of a parameter or a set of parameters in optimal allocations. Parametric sensitivity analyses are carried out in order to analyse the effect of approximations. Sensitivity analysis is carried out for tasks by changing efficiencies of end use devices. If a source can supply either partially or fully requirements of more than one task or if the task has access to various resources for its energy needs, the type and number of transitions depend on various critical parameters, such as, unit cost of sources used by a particular task, efficiency of energy conversion of different energy paths, limits on the availability of resources if any, etc. The emerging allocation of resources for various tasks thus depends on the combination of values of critical parameters. Thus, sensitivity analyses give a clear picture as to how a single parameter or a combination of parameters influences optimal scenarios in regional energy planning exercise. This would help in a dynamic situation that may arise while implementing regional energy plan using the optimisation techniques. When the cost of biogas for cooking is taken as Rs. 0.35/m3 and wood stove efficiency is around 10%, biogas is preferred for cooking. When efficiency of wood devices is increased in steps of 5%, it is noticed that, at efficiency greater than 30%, wood stoves are preferred for cooking while biogas enters lighting option. This shows that at low level of efficiency, wood stove is not economical, as biogas or electricity generated from hydro resources in a decentralised way is inexpensive. However, this scenario changes with increase in efficiency of wood energy devices beyond 30%. Hence, between 10 and 30% efficiency of wood devices, firewood supplements the available biogas in meeting the domestic needs of a region.