UCSF Achieved Goal of Carbon Neutral MRI Service in 2022

MRI systems are known to consume substantial electrical power that can contribute to carbon emissions.  UCSF’s Department of Radiology and Biomedical Imaging hosts over 20 MRI systems across its various campuses.  The majority of these scanners operate on inherently carbon free clean energy, but some systems are powered from methane gas and have a carbon footprint.

Electrical power meters have been placed on 50% of our MRI systems and have allowed us to understand their power use characteristics.  We used this information, along with an MRI instrument’s specific hours of operation and number of patients scanned, to project the energy use of all our scanners not employing green energy.  This projection concluded that MRI instruments that utilized methane gas power sources consumed 738MWh of electricity in 2022.  This correlates to 226 metric tons of carbon emissions associated with the operation of these instruments.

The American Carbon Registry (ACR) is a global carbon crediting program that seeks to catalyze carbon emission reductions.  It issues cardon credits that are vetted to ensure the originating offset contributes to real emission reductions and has been utilized by UCOP.  The Department of Radiology and Biomedical Imaging, via UCOP, retired ACR Carbon Credits that match our calculated carbon emissions from MRI instruments in 2022.  This purchase allowed us to realize our 2022 goal of achieving a carbon neutral MRI service at UCSF.

In 2023 the University of California shifted its focus from achieving carbon neutrality by 2025, to a longer-term goal that would reduce electricity produced by methane gas by 90% by 2045.  That switch reflected challenges in the carbon offset/credit marketplace that make it difficult to assure the purchased credits meet the desired goal.  The department is similarly shifting its strategy and has begun exploring methods of reducing MRI energy use and improving the amount of energy required to perform an MRI examination.  These efforts include utilizing low power modes when scanners aren’t active and employing acceleration methods and deep learning reconstruction methods to reduce scan times.  Thus, while the university shifts to cleaner energy sources, we hope to moderate the power demands of our growing MRI service.  Collectively these efforts reflect the universities commitment to a more sustainable future.

To learn more about University of California’s sustainability goals, please visit
https://sustainabilityreport.ucop.edu/2024/locations/uc-san-francisco/