Based on evidence that certain human-made chemicals endanger human health and the environment by depleting stratospheric ozone, the world community is seeking ways to eliminate their production and use. The United States is the largest user of these chemicals and the Department of Defense (DoD) is the largest user in the United States. As DoD reduces its use of these chemicals, some fear that its energy consumption will rise, complicating DoD's ongoing efforts to increase energy efficiency. This report asks how important this problem is. It finds that reducing the use of chemicals that deplete ozone is not likely to increase DoD's energy use much relative to its total energy use and could even reduce its energy use. Even if it did raise DoD's energy use, this effect should not affect DoD's choice of appropriate alternatives; concerns about the relative efficacy, effects on health and safety, and cost of alternatives would dominate energy concerns. Hence, the report advises DoD not to give substantial policy attention to limiting the energy effects of substituting alternatives for chemicals that deplete stratospheric ozone.