<< Click to Display Table of Contents >> Navigation:  Project design > Simulation > Simulation process: pumping system

See also Simulation Process: irradiance and PV array

Once the Incident Global Effective irradiation and the MPP running conditions are determined, the system simulation is dependent on the  Pumping System Type and Configuration.

In any case, and for any running hour, the simulation has to determine the Flowrate furnished by the pump, as a function of the Head and the available electrical energy (from PV array, or eventually battery). As the head at the pump is dependent on the flowrate (due to friction losses, and eventually drawdown level), this calculation always results from an iterative process.

Also at any hour (night and day), some water is drawn from the tank by the users (this quantity is defined by the specified "User's needs", and supposed to be constant, over the day and even over the month). The simulation has to manage the situations where the tank is full (limiting the pump's flow at the user's draw, and stopping the pump during the rest of the hour), and when the tank is empty (the user's needs cannot be satisfied).

For obtaining a consistent balance, all energies (below threshold, before producing flow, or potential unused energies when the pump is stopped) should be carefully accounted for, in any running situation. Along with the running losses (like inefficiencies, or I/V mismatches with respect to MPP), these numerous energy contributions allow to construct a coherent Loss diagram , which is a powerful tool for identifying the system weaknesses.

Nevertheless this losses structure is dependent on the system types and configurations. The simulation variables are specific to a system layout, or the order of the losses take place in a different order.

The final relevant results include mainly the water delivered to the users, the missing water, the excess (unused) PV energy, and the system efficiency during the year (or performance ratio).  And if economical features are defined, the global investment, yearly costs and cost of the pumped m³.