.. _quickstart:

Quickstart
==========
Hopefully this tutorial can get you up and running fast.

.. include:: ../../../README.rst

Example
=======
In this example let's make a PV system of 2 strings with 8 modules each using
standard 96 cell modules. You can enter these commands in the Python
interpreter, run them from a script or simply paste them in
`IPython <http://ipython.org/>`_ with ``%paste``. ::

    >>> from pvmismatch import *  # this imports everything we need
    >>> pvsys = pvsystem.PVsystem(numberStrs=2, numberMods=8)  # makes the system
    >>> from matplotlib import pyplot as plt  # now lets make some plots
    >>> plt.ion()  # this turns on interactive plotting
    >>> f = pvsys.plotSys()  # creates a figure with the system IV & PV curve

    >>> pvsys.Vmp  # max voltage [V]
    434.78820171467481

    >>> pvsys.Imp  # max current [A]
    11.821752935151656

    >>>pvsys.Pmp  # max power [W]
    5139.9586997897668

    >>> pvsys.FF  # fill factor
    0.78720728660102768

    >>> pvsys.eff  # efficiency
    0.21824347997841023

    >>> pvsys.Voc  # open circuit voltage [V]
    517.7428517321761

    >>> pvsys.Isc  # short circuit current [A]
    12.611199981080691

.. image:: pvsys_plot_2x8-std96.png

Now lets shade the last row of the 1st module in the 1st string::

    >>> pvsys.setSuns({0: {0: [(0.2, ) * 8, (11, 12, 35, 36, 59, 60, 83, 84)]}})
    >>> f_shade = pvsys.plotSys()

.. image:: pvsys_plot_2x8-std96_last_row.png

How is this system doing now? ::

    >>> pvsys.Vmp
    402.2176762133148

    >>> pvsys.Imp
    11.782413660383165

    >>> pvsys.Pmp
    4739.0950426633335

    >>> pvsys.FF
    0.72444923136011019

    >>> pvsys.eff
    0.2020646802535036

    >>> pvsys.Voc
    517.5628797316385

    >>> pvsys.Isc
    12.63933841066166

That did a little damage - the system lost 400[W] about 8%. Let's see what's
actually going on with those cells in the last row of the 1st module in the
1st string. ::

    >>> pvsys.pvmods[0][0].pvcells[0]  # let's see if they're actually shaded
    <PVcell(Ee=1[suns], Tcell=298.15[K], Isc=6.3056[A], Voc=0.67444[V])>

    >>> [pvsys.pvmods[0][0].pvcells[_] for _ in (11, 12, 35, 36, 59, 60, 83, 84)]
    [<PVcell(Ee=0.2[suns], Tcell=298.15[K], Isc=1.26112[A], Voc=0.630143[V])>,
     <PVcell(Ee=0.2[suns], Tcell=298.15[K], Isc=1.26112[A], Voc=0.630143[V])>,
     <PVcell(Ee=0.2[suns], Tcell=298.15[K], Isc=1.26112[A], Voc=0.630143[V])>,
     <PVcell(Ee=0.2[suns], Tcell=298.15[K], Isc=1.26112[A], Voc=0.630143[V])>,
     <PVcell(Ee=0.2[suns], Tcell=298.15[K], Isc=1.26112[A], Voc=0.630143[V])>,
     <PVcell(Ee=0.2[suns], Tcell=298.15[K], Isc=1.26112[A], Voc=0.630143[V])>,
     <PVcell(Ee=0.2[suns], Tcell=298.15[K], Isc=1.26112[A], Voc=0.630143[V])>,
     <PVcell(Ee=0.2[suns], Tcell=298.15[K], Isc=1.26112[A], Voc=0.630143[V])>]

    >>> f_mod00 = pvsys.pvmods[0][0].plotMod()  # plot that module
    >>> f_mod00cells = pvsys.pvmods[0][0].plotCell()  # plot all the cells

    >>> import numpy as np  # let's find the string current by interpolatign
    >>> np.interp(pvsys.Vmp, pvsys.pvstrs[0].Vstring, pvsys.pvstrs[0].Istring)
    5.624635929989247

.. image:: pvmod00_plot_2x8-std96_last_row.png
.. image:: pvmod00cells_plot_2x8-std96_last_row.png

Interpolation of string current from the system voltage yields 5.6[A]. Those
shaded cells can only carry that current in reverse bias, so they must be hot!
Let's change their temperatures. In fact since the temperatures are still at
25[C], let's update the normal cells too::

    >>> pvsys.setTemps(50. + 273.15)  # [K] normal cells
    >>> pvsys.setTemps({0: {0: [(100. + 273.15, ) * 8, (11, 12, 35, 36, 59, 60, 83, 84)]}})  # [K] hot cells in RBD

    >>> pvsys.pvmods[0][0].pvcells[0]  # let's see if they're actually hot
    <PVcell(Ee=1[suns], Tcell=323.15[K], Isc=6.36158[A], Voc=0.63443[V])>

    >>> [pvsys.pvmods[0][0].pvcells[_] for _ in (11, 12, 35, 36, 59, 60, 83, 84)]
    [<PVcell(Ee=0.2[suns], Tcell=373.15[K], Isc=1.29471[A], Voc=0.497765[V])>,
     <PVcell(Ee=0.2[suns], Tcell=373.15[K], Isc=1.29471[A], Voc=0.497765[V])>,
     <PVcell(Ee=0.2[suns], Tcell=373.15[K], Isc=1.29471[A], Voc=0.497765[V])>,
     <PVcell(Ee=0.2[suns], Tcell=373.15[K], Isc=1.29471[A], Voc=0.497765[V])>,
     <PVcell(Ee=0.2[suns], Tcell=373.15[K], Isc=1.29471[A], Voc=0.497765[V])>,
     <PVcell(Ee=0.2[suns], Tcell=373.15[K], Isc=1.29471[A], Voc=0.497765[V])>,
     <PVcell(Ee=0.2[suns], Tcell=373.15[K], Isc=1.29471[A], Voc=0.497765[V])>,
     <PVcell(Ee=0.2[suns], Tcell=373.15[K], Isc=1.29471[A], Voc=0.497765[V])>]

    >>> pvsys.Vmp
    370.60261850573403

    >>> pvsys.Imp
    11.924151410534137

    >>> pvsys.Pmp
    4419.1217362027928

    >>> pvsys.FF
    0.71233263744268427

    >>> pvsys.eff
    0.1884217160847011

    >>> pvsys.Voc
    486.4780520368573

    >>> pvsys.Isc
    12.752339637569314

    >>> f_hot = pvsys.plotSys()

.. image:: pvsys_plot_2x8-std96_last_row_hot.png

Take note:

* For normal cells Voc decreases as expected when temperature is increased from
  25[C] to 50[C] under the same 1[sun] conditions from 0.67444[V] to 0.63443[V].
  The equivalent :math:`\beta V_oc = 0.15 \left[ V / C \right ]` for 96-cells.