The methodology used for assessment of potential savings at macro level is as follows. Relevant data from an energy audit database for each type of and each size of commercial buildings is extracted. The data are then used to find values of parameters relevant to energy use for lighting, air-conditioning, and other end-uses of each building type and each size. These parameters are used to either form a building model of each building type and size, or are used to adjust other parameters so that each building model possesses features that are consistent with the values of these parameters. The resulting models are called base case or reference models.