Recent developments in firm location analysis are applied to explore the concentration patterns of firms making up the green energy sectors in 2002 and 2006. A two-step procedure is applied in this analysis. First, Guimarães, Figueiredo, and Woodward’s spatial adaption of Ellison and Glaeser’s industry concentration index are applied to estimate the degree to which firms making up the so-called green energy sectors tend to exhibit concentration. In the second stage, the spatial distribution of concentration is analyzed using a statistical framework, also suggested by Guimarães, Figueiredo, and Woodward. Preliminary results suggest that green energy subsectors exhibit significant global concentration, but localized concentration appears to be random.