Operational Cost Savings Opportunities for MRI Scanners: Preprint

Medical imaging equipment accounts for about 5% of whole-building energy use in U.S. healthcare. Magnetic resonance imaging (MRI) scanners are the most energy- and cost-intensive equipment, reaching up to $60,000 in utility bills annually per scanner. MRIs often operate up to 90% of the time in nonproductive modes (i.e., not scanning patients). Many modern MRI systems have low-power mode (LPM) hardware and software configurations to reduce energy use during nonproductive time, but technologists, radiologists, and healthcare facility staff are rarely aware of these options, which limits their use. This study quantifies the potential energy and cost savings in the U.S. from the use of MRI LPM. We applied a load duration curve method to metered power data from 20 MRI scanners in four U.S. healthcare facilities to establish operating mode power thresholds. Using these thresholds, we categorized the time spent in each mode and quantified the associated energy use and costs. Our analysis shows that depending on the scanner, MRI devices may have one or more power levels within the nonproductive modes. Shifting from higher-power modes to lower-power alternatives during nonoperating hours therefore highlights opportunities for savings. Finally, we extrapolated the results of the individual scanners to estimate the potential national impact. The results highlight a number of opportunities for energy and cost reductions through the adoption of LPM. In addition to total annual energy use, this work also provides a mode-specific breakdown of MRI electricity costs, offering new insights for efficiency and resilience planning in healthcare facilities.