Davenergy conducted retro-commissioning and prioritized cost-effective energy and water efficiency measures of 4,000,000 square feet in existing buildings, totaling 60 buildings. ASHREA Level 2 Energy Audits were also required. The purpose of the retro-commissioning program was to assist USDA in optimizing the operation of Heating, Ventilating and Air‐Conditioning (HVAC) systems for reducing energy costs and bringing equipment to its proper operational state. Davenergy completed a detailed investigation of the building HVAC systems, including functional tests of equipment and control systems, analysis of available Building Automation System (BAS) trend data provided, As-Built mechanical plans for the building, and As-Built BAS Sequence of Operations specifications. Davenergy identified energy conservation measures for NBSD resulted in 5,775 MMBtu, 249 kW, and $152,852 annual savings in energy usage and cost. This is a 13% reduction in energy consumption and a 10% reduction in cost for the buildings serviced.