Taking the guess work out of your site visits is paramount when selecting a location for a solar installation. One of the best tools out there is the Solar Pathfinder.
Metro Solar Atlanta uses the Solar Pathfinder before all of our solar hot water installations.The Solar Pathfinder operates on a very simple premise. It uses a reflective dome to give a panoramic view of the entire site.
The installer sets up the Solar Pathfinder in the proposed location where the solar collectors will be located, typically on the roof. Declination is accounted for prior to the setup.
A small compass on the pathfinder is used to make sure that the unit is oriented to due south.
Once in position the unit is leveled using a bubble level built into the unit.
Once the unit is in place a digital photograph is taken of the dome. The dome reflects all of the obstructions at the site onto a sunpath diagram.
The sunpath diagrams are latitude specific and allow you to convert the view on the dome into useful information. The outline of the trees reflected onto the dome reveals where the shading will occur at a specific point in time on the diagram. Deciduous trees that will lose their leaves in the fall or grow them in the spring can also be taken into account. A pen is used to trace the outline of the trees onto the paper diagram, or you can import the digital photo into a computer and use a drawing program to trace the outline.
Here the sunpath diagram is shown without the dome. The diagram represents the path of the sun at different times and during different months.
If you are an installer a Solar Path Finder is definitely worth the money at around $200. If you are a potential solar consumer insist your installer use a Solar Path Finder or other similar device before any solar installation, whether it’s PV or solar thermal. They can also be used for landscaping and other similar functions.