A recent study has shed a little light on power consumption in radiology departments, and it could help some providers go green while saving money in the process. A group of Irish researchers have found that in their department, electronic equipment left on when not in use generated as much CO2 emissions in one year as 10 passenger cars.
Led by Colin J. McCarthy, MB, BCh, FFR, of St. Vincent’s University Hospital in Dublin, the researchers used a power monitor to calculate power consumption of different devices around the hospital’s radiology department. The researchers focused particularly on calculating financial and environmental costs of leaving equipment on overnight and during weekends.
“We sought to evaluate the power consumption of various devices around the radiology department, audit our use of recycling, and review efforts by vendors to reduce the environmental impact of their products,” McCarthy and colleagues wrote.
Radiology departments, they explained, use large amounts of energy to scanners, interventional radiology suites and PACS. In addition, powering general office equipment like air conditioners, lights and desktop computers added to a department’s power consumption.
Data collected during the study period showed numerous areas with room for improvement in reducing energy consumption.
Of 27 PACS reporting stations monitored, 25 were left on overnight and during weekends. Nine stations had sleep mode and 16 stations had monitors with a screensaver. The average power consumption was 297 watts. None of the computers had sleep or standby mode enabled and over the course of a year, these unused machines consumed 47,490 kilowatts per hour of electrical energy—a total cost of $4,749.
Of 43 desktop computer stations, 29 were left on overnight and/or during weekends. Over the course of the year, the power consumed by the unused machines equaled 25,040 kilowatts per hour—a financial cost of $2,504 and estimated greenhouse emissions of 17.7 metric tons of carbon dioxide, similar to 3.7 cars.
The team also looked into electrical usage to keep the department cooled. Ceiling-mounted air conditioning units in the facilities were left on four nights out of seven, and when the two rooms were cooled overnight, the cost amounted to $3,709 and 26.2 metric tons of carbon dioxide—equivalent to 5.5 passenger cars per year.
“Simple steps such as turning off computers and air-conditioning units and enabling 'sleep mode,' where possible, can produce significant savings,” McCarthy and colleagues wrote.