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This gives a step-by-step procedure when defining a stand-alone system in PVsyst.

First step:

As for any PVsyst system, you have to specify the orientation of the PV array.  

In the present time (V.6.40), you cannot define several sub-arrays, therefore also several orientations. This will be improved in the next versions.

Second step:

You are asked to define the user's needs.

By default for little systems, this is proposed  as a list of domestic appliance and the details of their use (may be seasonal or monthly).

For industrial or bigger systems, you have many possibilities of defining a load profile (including by a list of hourly values).

Third step:

Open the button "System".

The Pre-sizing tool (on top) gives advice about the required Battery bank and PV array power.

The calculation is based  on your meteo files and above definitions. You should define:

-  the required autonomy (usually around 4 days),

-  the acceptable probability that the needs are not covered by the system (PLOL for "probability of Loss of Load),

-  the nominal voltage of the battery bank.  

The program will then perform a system sizing, in a similar way as in the "Presizing" section.

You also have a button for a more refined sizing study, for different meteo distributions, or according to the PLOL parameter.

Forth step:

Define the battery pack, by choosing a battery model   ("Storage" page).

=> The program will propose the number of batteries in series and in parallel, according to the suggestions obtained in the previous pre-sizing tool.

You should also define the operating temperature conditions for the batteries, according to your system implementation.

Fifth step:

Define the array configuration and control strategy   ("PV array" page)

- Acknowledge the pre-sizing propositions  (planned power or available area),

- Choose a PV module model in the database,

- Choose the control strategy  (direct coupling, MPPT or DCDC converter).

In a first step, you are advised to choose the "Universal controller", to get rid of the specific control conditions.

NB: With the  "Direct coupling" strategy, the PV module voltage should match the battery voltage in operation. Any mismatch will result in "Pmpp losses".

During this first stage, you can do some studies by varying the operating conditions, namely the operating thresholds for the Charging / Discharging commands. You can modify these thresholds within the "Universal controller".

Only during a second phase of your project, when the system configuration will be well established and will give globally the expected results in terms of PLOL or unused energy, you will choose a specific commercial model of controller.

NB: you can create your own controller model, suited for your system (for example for parametric studies) by simply saving the Universal model in its actual configuration.  In this case, please give it its manufacturer's and model's name, and save it using the convention  "Manufacturer_Model.RLT"   in your own database.

Sixth step:

In the "Back-up" page, you can specify a Diesel Genset, and adjust its operating (charging) power).

NB: In the present time, you cannot define an inverter with stand-alone systems: the user's needs are expressed in terms of Energy, whatever the DC or AC use. If you have an inverter you should increase the user's needs, in order to account for its efficiency.  Stand-alone inverters will be available soon, in a future version.

Seventh step :

Pass to the button "Detailed Losses" for the definition of all system losses, which have been defined at reasonable default values for your first simulations.

Finally :

You can now play with these parameters, and retrieve the automatic proposed values by clicking on the associated default checkbox at any time.

Warnings will be displayed if there are some incompatibilities between the chosen parameters. Red warnings are not acceptable (simulation cannot be performed) and orange warnings are indicative. These colours will be thrown back on the "System" LED's button.