Our review disclosed that the Department had not always effectively identified and implemented energy-saving opportunities through facility evaluations and electricity metering. Three of the five sites we reviewed (Brookhaven National Laboratory, Oak Ridge National Laboratory, and Los Alamos National Laboratory) had not always identified or implemented low- and no-cost, quick payback energy conservation measures discovered during facility evaluations. In addition, two of the five sites (Oak Ridge National Laboratory and the Y-12 National Security Complex) had not fully evaluated existing buildings to determine, among other things, whether building systems such as heating and lighting were operating as intended, despite specifically identified savings and recommendations to do so. In regards to metering, we identified opportunities at two sites visited to improve energy conservation through the use of electricity metering data. Although a number of factors contributed to instances of ineffective evaluations and electricity metering practices, effectively evaluating systems in existing buildings and using electricity metering data could significantly reduce energy costs and increase energy efficiency across the Department. We conservatively estimate the Department could save approximately $6.6 million annually if it more proactively assesses and repairs building systems through facility evaluations. We made several recommendations designed to assist the Department in its efforts to conserve energy and decrease costs through evaluations of existing buildings and electricity metering. Management concurred with our recommendations and provided actions that will be taken to address issues identified in our report.