Energy modeling – software simulation of building energy use – isn’t just for new construction—when used correctly, it’s a powerful tool for planning and validating cost-effective retrofits in existing facilities. This session will demystify the role of energy simulation and analysis in identifying and prioritizing upgrades that deliver real operational savings. The speaker will describe the key eligibility requirements of the Federal 179D Energy Efficient Commercial Buildings Tax Deduction, with details on how facility owners can benefit from designer allocations, and how documentation is structured. Included will be examples of how public-sector entities (schools, universities, municipalities) are leveraging 179D. Gain clarity on how to collaborate with design teams and tax advisors to optimize and capture this incentive.