This report outlines a method to assess the local potential for deployment of distributed energy resources (DER), small power-generation installations located close to the point where the energy they produce will be consumed. This methodology combines established economic optimization techniques with a geographic information system (GIS) analysis of local land-use constraints that limit the use of distributed generation (DG) systems. This methodology was developed using an example case in the San Diego area. Our work approaches DER adoption from a customer perspective, based on the premise that future development of DER may take the form of microgrids (μGrids), where multiple neighboring end users are aggregated, and energy loads and generation are jointly managed using standardized "plug and play" power electronics. Previous work in the field of power system planning has focused on the electrical requirements and economic feasibility of incorporating μGrids into the current power-supply infrastructure. However, although local restraints such as zoning codes and on-site physical barriers are well-known frustrations in the field of DER, no analysis method has been developed to address them. The need for such a method is the inspiration for this work. By incorporating established DER analysis techniques with a GIS, local spatial constraints on DER can be readily addressed and analyzed. GIS currently plays an essential role in transportation and city infrastructure planning; we propose that it can play a similarly important role in future DER deployment.