Free Solar Panel Simulation at http://YachtSoftware.Org

The IcarusSolarDesigner, a free simulation, is available at http://YachtSoftware.Org that predicts the output of a solar panel marine installation at any time of the day, at any latitude from the North to the South Pole and for any cloud cover.  It is an Excel based spreadsheet that uses a Visual Basic back end to predict the output for a boat installation where the orientation of the panels may change with the boats heading.  It can be used to design an installation at your home port that will work to provide all your energy needs as you cruise any where in the world.  It is also handy in allowing the user to directly compare his own measurements with the predictions.  On our boat s/v Star we were able to evaluate the effect of shading from our radar and discovered that we had only a 50% efficiency that was easily fixed by moving the radar to another close by location.  We ask for donations through PayPal.com if the software is useful for your application.