Solar photovoltaic (PV) energy has by now been established as a cost-effective alternative to fossil fuels, especially when benchmarked against diesel generators. And yet, it is the same costly diesel generators that are commonly found in areas that are struggling to achieve a reliable electricity supply. The potential to lower operating costs and improve reliability of supply by hybridizing these diesel generator-based grids through the integration of PV systems is significant. However, a major hurdle to hybridization is the access to affordable financing resulting from high perceived risk on pre-investment modelling. The key evaluation criterion for the financial performance of PV integration is the actual savings on the clients’ diesel consumption. 
In order to be bankable, the fuel savings calculation of a hybrid system needs to prove that it is based on strong and comprehensive assumptions. To facilitate this step of project development, VDE, together with GIZ, have developed a standard for certifying load measurements and fuel saving calculations. The standard is made up of four parts: 1) a procedure for load measurements and a methodology for extrapolation, 2) a definition generator input parameters required for the simulation of hybrid power generation, 3) the definition of input parameters for storage devices (optional, in case these are part of the system), and 4) the fuel savings simulation itself to which parts 1-3 constitute the inputs used. Fuel savings simulations may be certified according to ‘Procedure B’, which means that basic requirements have been met, or ‘Procedure A’, which means that more stringent requirements have been met. An issued certificate will serve as a seal of quality on the financial performance of a project in order to establish trust amongst end-client, project developer and financiers.
Interested parties who would like to have their fuel savings simulations certified according to the new standard may inquire with VDE: renewables@vde.com