Solar resource data
SISIFO requires, as input data, time series of horizontal irradiances and ambient temperature coming, for example, from the monitoring of PV plants, typical meteorological years, ground-based meteorological stations or satellite databases. You can run SISIFO introducing your own solar resource data file, with any time step, using an excel template that must be uploaded to the server.
Besides, if these time series are not available, SISIFO may generate them starting from the 12 monthly-averages of the daily global horizontal irradiation, and maximum and minimum ambient temperatures. For a system location in Europe, Africa and Asia, these monthly averages may be automatically imported from the public-domain database PVGIS.
For system locations outside PVGIS, it is planned to extent the automatic ingestion of data to other public-domain solar resource databases, such us the NREL National Solar Radiation Database data sets (e.g., TMY3) and SWERA.
Models and algorithms
Once time series have been read or generated, SISIFO calculates the incident radiation on the plane of the PV generator and the impact of the angle-of-incidence, soiling, self-shading and solar spectrum.
You can select among three static PV generators (on ground, roof or façade) and five solar trackers with the possibility of the backtracking mode of operation.
Modeling of PV generators and inverters is based on technical parameters provided by the manufacturers (datasheets), which can be also later measured in on-site experimental testing campaigns. This approach is useful, on the one hand, for ensuring the technical quality of the PV system. And, in the other hand, for tuning the simulations and reducing the uncertainty of energy yield predictions.
You can select among basic and advanced simulation options depending on your technical expertise. Advanced options allow the selection of models to be used in the sequence of algorithms.
If you are interested in project finance or electricity cost calculations, SISIFO may calculate, first, the yearly incomes related to the simulated annual electricity production during the project lifetime, according to the indicated feed‐in tariff. Second, the annual operating expenses, payment of the loan capital, interests, and annual cash flows. Finally, it evaluates the Levelised Cost of Electricity (LCOE), taking into account the previously calculated global energy production and the overall expenses.
SISIFO calculates the times series of all the simulated variables that are integrated for obtaining and displaying daily, monthly and annual performance parameters (irradiations, electricity production, performance ratios, etc.). Besides, SISIFO may provide a basic project finance analysis and/or generate a technical simulation report in pdf format.
For a quickly understanding of the interfaces, here are video tutorials (do not forget to enable the subtitles):