Performance Path using S.P.O.T.

Hello Mark, For clarity, Option 1 is the Simulation Option. I do not believe SPOT can be used because LEED requires that the calculation be done for the space without the contribution due to the electric lighting and SPOT requires that you have at least one electric light. There may be a work-around but I have not looked into it that far. I know Radiance can be used on its own for calculations or with Rayfront and other software that uses it as the calculation engine. There is a comprehensive list here, although you would have to look at the features of each to know which can perform the calcuations LEED wants. http://apps1.eere.energy.gov/buildings/tools_directory/subjects.cfm/pagename=subjects/pagename_menu=materials_components/pagename_submenu=lighting_systems

As a follow-up I did find out that SPOT will calculate the daylighting contribution without the electric lighting. You need to enter in some kind of electric lighting, but if you're only interested in the daylighting results, just enter in a "dummy" lighting system. However, SPOT will only calculate for very simplistic geometry.