Researchers at UCSF highlight an easily overlooked best practice
One very simple way to cut MR energy consumption by over 25%
May 01, 2023
By Gus Iversen and John R. Fischer
Healthcare is responsible for approximately 4.4% of all global carbon emissions, and the MR suite is a particularly energy-intensive piece of the puzzle. It makes sense that these powerful scanners sap a lot of resources, but new research suggests one small change can significantly slash MR’s carbon footprint.
At UCSF, the radiology department partnered with Siemens and Siemens Healthineers to evaluate MR energy consumption and look for opportunities to operate scanners more efficiently. Their findings, based on four scanners from three different vendors, yielded at least one no-brainer best practice: Use the “off mode”.
“A lot of radiologists don't think about the operations of our machines, but the machines have several different power modes they can be placed in,” Dr. Sean Woolen, assistant professor and director of UCSF Radiology’s sustainability initiative, told HCB News. “So we looked at switching to the ‘off mode’ to consume less energy, and also optimizing that particular mode to consume even less energy by modulating some of the hardware components.”
A misunderstood setting
According to Woolen, the term “off mode” can cause confusion, (nobody wants to risk completely shutting down the MR, which would allow the magnet to warm up and create all kinds of costly chaos). Often, “idle mode” may be used overnight, even though “off mode” is a lower energy alternative that can be used when scanning is done for the day.
“Surprisingly, all vendors had somewhat similar savings from switching from an idle to an off mode,” Woolen said, referring to the study data, which was collected using Siemens’ power-monitoring and management technologies. “They all reduced power consumption by about 25% to 33%.”
One of the two Siemens Healthineers scanners in the study, the MAGNETOM Vida 3T MR, has an additional “power save” mode, which further decreased power usage during off hours by an additional 22% to 28% compared to “off mode” usage. It does this by turning off the compressor and monitoring the magnet’s temperature, (which must be -270 degrees Celsius), and turning the compressor back on when it exceeds certain thresholds.
“Even though that was only available from one vendor, we simulated the additional power save mode for the other two vendor's devices, and we achieved similar savings,” said Woolen.
Cutting waste is good business
According to Vibhas Deshpande, vice president of sustainability innovation and strategic research at Siemens Healthineers North America, reducing idle time in between patients can additionally reduce energy consumption.
“Even during their use time, there are ways one can reduce energy, but that will be the subject of further research,” he told HCB News.
Being mindful of MR scanner modes doesn’t just reduce carbon emissions. The researchers found that embracing “off mode” could result in annual savings of $1,717 to $2,943 per year for a single machine. If the machine can be put into “power save” mode, or simulate that mode, there’s an additional $1,226 to $1,594 to be saved annually per scanner.
“If all outpatient MR scanners in the U.S. implemented a ‘power save’ mode instead of an ‘off mode’ for 12 hours overnight, it would save enough energy to power 6,889 homes a year in the U.S,” said Woolen.
Environmental change is up to all of us
Prior research on energy usage in the radiology department played a role in UCSF focusing on reducing carbon emissions in the radiology department. In 2020, a study in Radiology showed that 33% of MR energy consumption was attributed to the system-off state, owing to the need for constant helium cooling and coldhead operation.
Although Woolen and his team did not face resistance from colleagues when tinkering with scanner modes, there were aspects of the research that caused some uneasiness.
“There is a power cycling time, meaning there is a time for the machine to power down and power back up,” he said. “This can range anywhere from five to 20 minutes, so one concern is that if you turn off the machine it might not be available to use immediately.”
Getting everyone on the same page was critical. For their study, the team engaged with electrical engineers, facilities engineers at the hospital, sustainability experts, as well as vendor experts from Siemens Healthineers and the energy experts from Siemens.
“In general, coordinating environmental change in a healthcare system takes a system's leadership approach,” said Woolen. “Radiologists may be used to working with individuals in their department or one other specialty like on a clinical study, but particularly for environmental projects, usually you have to engage a lot of individuals from different disciplines.”
For UCSF, the MR energy study is the beginning of an initiative to reduce power consumption in the radiology department. “We have plans to look at further ways to become more energy efficient and reduce our waste, but we're still in the beginning stages of those,” said Woolen.
Healthcare is responsible for approximately 4.4% of all global carbon emissions, and the MR suite is a particularly energy-intensive piece of the puzzle. It makes sense that these powerful scanners sap a lot of resources, but new research suggests one small change can significantly slash MR’s carbon footprint.
At UCSF, the radiology department partnered with Siemens and Siemens Healthineers to evaluate MR energy consumption and look for opportunities to operate scanners more efficiently. Their findings, based on four scanners from three different vendors, yielded at least one no-brainer best practice: Use the “off mode”.
“A lot of radiologists don't think about the operations of our machines, but the machines have several different power modes they can be placed in,” Dr. Sean Woolen, assistant professor and director of UCSF Radiology’s sustainability initiative, told HCB News. “So we looked at switching to the ‘off mode’ to consume less energy, and also optimizing that particular mode to consume even less energy by modulating some of the hardware components.”
Dr. Sean Woolen
According to Woolen, the term “off mode” can cause confusion, (nobody wants to risk completely shutting down the MR, which would allow the magnet to warm up and create all kinds of costly chaos). Often, “idle mode” may be used overnight, even though “off mode” is a lower energy alternative that can be used when scanning is done for the day.
“Surprisingly, all vendors had somewhat similar savings from switching from an idle to an off mode,” Woolen said, referring to the study data, which was collected using Siemens’ power-monitoring and management technologies. “They all reduced power consumption by about 25% to 33%.”
One of the two Siemens Healthineers scanners in the study, the MAGNETOM Vida 3T MR, has an additional “power save” mode, which further decreased power usage during off hours by an additional 22% to 28% compared to “off mode” usage. It does this by turning off the compressor and monitoring the magnet’s temperature, (which must be -270 degrees Celsius), and turning the compressor back on when it exceeds certain thresholds.
“Even though that was only available from one vendor, we simulated the additional power save mode for the other two vendor's devices, and we achieved similar savings,” said Woolen.
Cutting waste is good business
According to Vibhas Deshpande, vice president of sustainability innovation and strategic research at Siemens Healthineers North America, reducing idle time in between patients can additionally reduce energy consumption.
“Even during their use time, there are ways one can reduce energy, but that will be the subject of further research,” he told HCB News.
Being mindful of MR scanner modes doesn’t just reduce carbon emissions. The researchers found that embracing “off mode” could result in annual savings of $1,717 to $2,943 per year for a single machine. If the machine can be put into “power save” mode, or simulate that mode, there’s an additional $1,226 to $1,594 to be saved annually per scanner.
“If all outpatient MR scanners in the U.S. implemented a ‘power save’ mode instead of an ‘off mode’ for 12 hours overnight, it would save enough energy to power 6,889 homes a year in the U.S,” said Woolen.
Environmental change is up to all of us
Prior research on energy usage in the radiology department played a role in UCSF focusing on reducing carbon emissions in the radiology department. In 2020, a study in Radiology showed that 33% of MR energy consumption was attributed to the system-off state, owing to the need for constant helium cooling and coldhead operation.
Although Woolen and his team did not face resistance from colleagues when tinkering with scanner modes, there were aspects of the research that caused some uneasiness.
“There is a power cycling time, meaning there is a time for the machine to power down and power back up,” he said. “This can range anywhere from five to 20 minutes, so one concern is that if you turn off the machine it might not be available to use immediately.”
Getting everyone on the same page was critical. For their study, the team engaged with electrical engineers, facilities engineers at the hospital, sustainability experts, as well as vendor experts from Siemens Healthineers and the energy experts from Siemens.
“In general, coordinating environmental change in a healthcare system takes a system's leadership approach,” said Woolen. “Radiologists may be used to working with individuals in their department or one other specialty like on a clinical study, but particularly for environmental projects, usually you have to engage a lot of individuals from different disciplines.”
For UCSF, the MR energy study is the beginning of an initiative to reduce power consumption in the radiology department. “We have plans to look at further ways to become more energy efficient and reduce our waste, but we're still in the beginning stages of those,” said Woolen.