The relative costs of operating and supporting Air Force active- and reserve-component units are an important consideration in programming the mix of forces for various missions. Unfortunately, there are no generally accepted or well-documented methodologies for compiling the costs and output measures to be included in these comparisons. This report describes the development of one such methodology and applies it to an exploration of force mix alternatives in several weapon systems. Using data from the Air Force Total Ownership Cost decision support system from fiscal years 2006 through 2010, the author estimates the cost of operating the C-130 tactical airlifter, KC-135 aerial refueler, and F-16 multirole fighter fleets in Air Force active and reserve components. The author highlights the ways in which cost considerations favor the active and reserve components differently and discusses how this can help determine a cost-minimizing active/reserve mix. A Methodology for Comparing Active- and Reserve-Component Flying Units' Costs Cost information with sufficient granularity is assembled and disseminated by the Air Force primarily in its Air Force Total Ownership Cost decision support system.

Appropriate comparisons can be made if unit costs are spread across outputs related to strategic demands, ongoing operational demands, and aircrew proficiency flying demands; total owned aircraft, total operational flying hours, and total flying hours, respectively, can be used as measures of these outputs. Active and Reserve Units Have Asymmetrical Cost AdvantagesFor the purpose of meeting strategic demands, reserve-component units provide mission-ready aircraft with competent aircrew and maintenance workforces at lower cost per aircraft than active units. In contrast, active units have often met operational demands at lower cost per flying hour. For units operating at the same scale, in terms of number of hours flown, reserve units have a lower cost per flying hour than active units. However, many more reserve units operate on a scale that is too small to realize available economies of scale, and these small-scale units have high flying costs per hour. Determining a Cost-Minimizing Active/Reserve Mix The model suggests that reducing operational demands would tilt the cost-minimizing mix in the direction of the reserve components, while reducing planned strategic capacity (fleet size) would have the opposite effect.

Cost Structures and Alternative Mixeshow to install an ac unit home Outputs and Costs per Outputac unit fan not turning Manpower, Personnel and Training Programbest central ac unit 2013 This report is part of the RAND Corporation technical report series. RAND technical reports may include research findings on a specific topic that is limited in scope or intended for a narrow audience; present discussions of the methodology employed in research; provide literature reviews, survey instruments, modeling exercises, guidelines for practitioners and research professionals, and supporting documentation; or deliver preliminary findings. All RAND reports undergo rigorous peer review to ensure that they meet high standards for research quality and objectivity.

Permission is given to duplicate this electronic document for personal use only, as long as it is unaltered and complete. Copies may not be duplicated for commercial purposes. Unauthorized posting of RAND PDFs to a non-RAND Web site is prohibited. RAND PDFs are protected under copyright law. For information on reprint and linking permissions, please visit the RAND Permissions page. The RAND Corporation is a nonprofit institution that helps improve policy and decisionmaking through research and analysis. RAND's publications do not necessarily reflect the opinions of its research clients and sponsors.Each air conditioner has an energy efficiency rating that lists how many BTU's per hour are used for each watt of power it draws. For room air conditioners , this rating is the Energy Efficiency Ratio, or EER. For central air conditioners, this rating is the Seasonal Energy Efficiency Ratio, or SEER. These ratings are posted on an Energy Guide Label, which must be attached in a visible place on all new air conditioners.

Many AC manufacturers are voluntary participants in the Energy Star labeling program. Energy Star labeled appliances indicate that high EER and SEER ratings. The air conditioner EER is its British thermal units (BTU) rating over its wattage. For example, if a 10,000-BTU air conditioner consumes 1,200 watts, its rating is 8.3 (10,000 BTU/1,200 watts). The higher the rating is, the more efficient the air conditioning unit is. However, a higher rating is usually accompanied by a higher price. Let's say that you are given a choice between two 10,000 BTU air conditioning units. To calculate what the payback period is on the more expensive unit, you need to know: Let's also say that you plan to use a room AC in the summer (approximately five months a year, depending on where you live) and it will be operating around eight hours a day. Say that the cost of a kilowatt-hour in your area is approximately $0.10. The difference in energy consumption between the two units is 200 watts, which means that every five hours, the less expensive unit will consume 1 additional kWh (and therefore $0.10 more) than the more expensive unit.

Assuming that there are 30 days in a month, you find that during the summer you are operating the air conditioner: 5 mo. x 30 days/mo. x 8 hr/day = 1200 hours [(1200 hrs x 200 watts) / (1000 watts/kW)] x $0.10/kWh = $24.00 Since the more expensive unit costs approximately $100 more, this means that it will take about four years for the more expensive unit to break even. Not all BTU ratings can be trusted. Just because the BTU's are stated to be high on specific models, this does not mean it is necessarily true. Some manufacturers will exaggerate the BTU's on units to raise the possibility of selling them and others will be more conservative to cause lower EER ratings, so keep in mind that a low room air conditioner EER may be misleading. It is best not to allow the energy rating to be your only criteria for choosing an air conditioning unit. Research the unit you are considering for your home and you will be happier with your purchase. Here you'll find a helpful Portable Air Conditioner Buying Guide .