MR and CT scans generate significant greenhouse gas emissions, but a new study on life cycle assessment (LCA) conducted at Vanderbilt University Medical Center suggests that solar power could be the key to dramatically reducing emissions.

The study, a collaboration between Vanderbilt and Philips Medical Systems Nederland B.V., evaluated energy use, resource consumption, and emissions across the full life cycle of MR and CT services, including equipment production, imaging operations, disposable supplies, pharmaceuticals, and linens.

MR services were responsible for an estimated 221 metric tons of CO₂-equivalent (CO₂e) emissions annually, roughly equal to the emissions of 52 gas-powered cars. CT services contributed 108 metric tons, or the equivalent of 25 cars per year. Energy consumption was the dominant source of emissions, accounting for 58% of MR-related and 33% of CT-related emissions, followed by disposable supplies and scanner manufacturing.
Most of the energy consumption occurred while scanners were idle. Across one month of monitoring, MR machines spent just 12% to 18% of their time actively scanning, with the majority of energy drawn during "ready-to-scan" and "low-power" modes. CT scanners showed similar patterns, consuming up to 72% of electricity while not actively scanning.

Researchers modeled the impact of transitioning to solar photovoltaic energy, which reduced MR emissions by 70% and CT emissions by 40%. Under this scenario, the relative emissions from supplies, scanner production, and linens became more pronounced.

Disposable supplies were another notable contributor. In the CT suite, gloves alone produced nearly 13,000 kg of CO₂e annually — 60% of supply-related emissions. Linens and contrast media also added meaningfully to the environmental burden.

To mitigate emissions, the authors recommend several strategies: sourcing cleaner electricity, improving scanner utilization, reducing idle power draw, and exploring circular procurement models for imaging equipment. Substituting reusable items for single-use supplies and reprocessing approved devices could also lessen environmental impacts.

“Reducing emissions from radiology requires action across the full supply chain — from how scanners are made and used, to how supplies are chosen and managed,” the authors concluded.

The study appears in the Journal of the American College of Radiology and was supported by contributions from academic researchers and sustainability consultants.

Back to HCB News

CT Homepage