Healthcare systems face growing pressure to reduce environmental impact while maintaining clinical quality. Medical imaging is a recognised contributor to energy use within hospitals, largely because complex equipment consumes electricity not only during examinations but also while idle. Mammography is one of the most frequently performed imaging procedures worldwide, forming the backbone of breast cancer screening and assessment pathways. Despite this scale, its direct energy profile has received little scrutiny compared with modalities such as computed tomography and magnetic resonance imaging. Recent measurements from a tertiary breast care centre provide detailed insight into how digital mammography and contrast-enhanced mammography consume electricity in routine practice, how energy use varies between machines and how operational choices influence overall efficiency. These findings are relevant for radiology departments seeking practical routes to sustainability without compromising patient care.
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Measuring Energy Consumption in Mammography Practice
Direct energy measurements were obtained from three mammography systems representing two vendors, capturing both standard digital mammography and contrast-enhanced mammography examinations. Energy use was monitored minute by minute at the wall outlet, allowing separation of electricity consumed during active imaging from background standby consumption. Net energy reflected the power required for each examination itself, while gross energy accounted for the redistribution of daily standby use across completed exams.
Across 193 examinations, clear differences emerged between machines. One system demonstrated higher net energy use per examination but achieved the lowest gross energy because it consumed very little power while idle. Another system required less energy during image acquisition yet showed higher overall consumption because of substantial standby use outside examination times. A third system used for contrast-enhanced mammography displayed net energy values comparable to standard digital mammography but substantially higher gross energy per exam when daily throughput was low. These observations underline that energy profiles are shaped not only by imaging technology but also by how machines are powered and utilised throughout the day.
Machine Design, Throughput and Efficiency
Statistical analyses confirmed that machine type was the dominant factor influencing energy consumption. Examination characteristics such as imaging technique, breast thickness and breast density showed no significant association with net energy use. This indicates that differences in electricity demand were driven primarily by equipment design rather than patient or procedural variables.
Daily workload played a critical role in determining efficiency. Systems performing higher numbers of examinations per day showed lower standby energy apportioned to each exam. This effect was most pronounced for contrast-enhanced mammography, where limited daily throughput magnified the impact of idle power consumption. As daily exam volumes increased, gross energy per examination fell sharply, demonstrating how scheduling and utilisation patterns can influence sustainability outcomes. Annual energy simulations reinforced these findings, with estimated consumption per machine ranging from approximately 1,660 to 2,300 kilowatt-hours depending on equipment and workload assumptions. Even under equal workloads, differences between machines persisted, highlighting inherent variation in energy efficiency across vendors.
Implications for Sustainable Breast Imaging
The overall energy demand of mammography was modest compared with other imaging modalities, placing it at the lower end of the radiology energy spectrum. Most electricity use was unrelated to the number of examinations performed and instead linked to keeping machines operational during idle periods. This creates clear opportunities for reduction through operational change rather than clinical compromise.
Contrast-enhanced mammography did not require more net energy per examination than standard digital mammography, despite involving dual-energy acquisitions. Its higher gross energy use was attributable to lower daily utilisation rather than the imaging process itself. These findings suggest that contrast-enhanced mammography can be integrated into clinical pathways without increasing direct electricity demand, provided machines are used efficiently.
Opportunities for improvement extend beyond simply switching machines off after hours. Consolidating appointments onto fewer systems and maximising daily throughput can significantly reduce idle energy consumption. Such measures align sustainability with workflow optimisation and resource efficiency. Given the large number of mammography examinations performed annually and the widespread availability of dedicated units, small per-machine savings could translate into meaningful reductions in energy use and associated emissions at scale.
Direct measurement of electricity consumption shows that mammography uses relatively little energy compared with other imaging techniques, yet avoidable inefficiencies remain. Standby operation rather than image acquisition is the primary driver of total energy use, with substantial variation between machines and strong dependence on daily workload. Standard digital mammography and contrast-enhanced mammography display similar net energy demands, indicating that enhanced imaging does not inherently increase electricity use. For healthcare organisations, these findings support practical strategies focused on equipment selection, scheduling and power management. By addressing idle consumption and optimising utilisation, breast imaging services can reduce their environmental footprint while continuing to deliver essential diagnostic care.
Source: European Radiology
Image Credit: iStock
