Evaluating the technical and economic performance of photovoltaic pumping systems : a methodology, final draft

The methodology consists of three performance tests - the photovoltaic array rating test, and long- and short-term performance tests - and a procedure to calculate the unit water cost. Instrumentation requirements and detailed procedures for carrying out the tests are specified, as are formats for evaluating and presenting results. The methodology was field-tested on five photovoltaic water pumps in Mali, of which three were performing well (producing water at unit costs of $0.20-0.35 per cubic meter). It was noted that villagers are unaware of the potential output of the pumps, and therefore may not realize if a fault develops. It is recommended that all photovoltaic pumps in Mali be tested, that the methodology and the sample results from Mali be circulated to organizations installing/operating solar pumps, and that a workshop and network of experts be organized to further improve and apply the methodology. Data obtained in Mali and references are appended.