A life cycle assessment of a diagnostic radiology department’s environmental footprint identified the energy consumption from imaging equipment as more than 50% of its greenhouse gas emissions, as well as opportunities to improve its sustainability.

Cities in developing nations have to deal with two significant sustainability challenges amidst rampant urbanization. First, consumer-generated food waste is increasing monumentally since open dumping is still followed as a predominant practice, the negative environmental externalities associated with food waste disposal are growing beyond manageable proportions. Second, the dependency on conventional fuels like diesel to operate transit buses, which is one of the major causes for deteriorating urban air quality. A nexus established between food waste management and operation of transit buses can improve the sustainable performance of cities in developing nations. In this study, a Life Cycle Assessment (LCA) supported Social Cost-Benefit Analysis (SCBA) is performed by considering a hypothetical scenario of establishing a large food waste treating biomethanation plant in Mumbai, India. The food waste from the city is transported to a biomethanation plant where it is subjected to an anaerobic digestion (AD) process. The biogas produced as a byproduct is upgraded to compressed biomethane (CBM) and used as a vehicle fuel to operate transit buses within the city. The LCA results suggest that CBM buses can reduce greenhouse gas and particulate matter emissions by 60% compared to diesel or compressed natural gas (CNG) buses. Fossil depletion potential of CBM buses is 98% lower than diesel, suggesting CBM’s importance in decoupling developing nations dependency on imported crude oil. The SCBA considers: (a) costs to stakeholders, i.e., fees for open dumping of food waste and cost of fuel for operating transit buses; and (b) social costs incurred by negative environmental externalities (obtained by monetizing LCA results) resulting from both, open dumping as well as fuel combustion. SCBA results indicate that the food waste-based CBM model can save 6.86 billion Indian rupees (USD 99.4 million) annually for Mumbai. The savings are made due to a reduction in stakeholder’s costs (fuel) coupled with societal, i.e., environmental externality costs if entire transit bus fleet operates on CBM fuel instead of conventional fuel mix (33:67 diesel to CNG) currently used. Although the study is performed for Mumbai, the results will be replicable to any city of developing nations facing similar issues.

To compare the total cost of ownership and environmental impact of linear and circular MRI business models at an academic medical center in the United States. We compared replacing an existing MRI scanner with a conventional linear business model (purchasing a new scanner) and two circular business models (purchasing an on-site upgrade or a refurbished scanner). We assessed the impact of these business models on total cost of ownership for the hospital. We also compared greenhouse gas emissions (GHGs) and materials used (kilogram) utilizing data from a life cycle assessment. Compared to a conventional linear purchase of a new MRI, circular business models reduced a) total cost of ownership by up to 21%; b) GHGs by up to 8% when using a conventional energy grid and 37% when using a renewable energy grid; and c) material use by up to 92%. We found that upgrading an existing scanner on site delivered the most beneficial gains, driven primarily through reuse of critical components. This study highlights the potential value of circular MRI business models for hospitals, patients and planet. By embedding innovative procurement strategies, imaging centers can deliver care with less cost while reducing GHGs and saving critical materials. We recommend that hospitals consider upgrading existing MRI scanners on-site or purchasing refurbished scanners before replacing with entirely new ones. We also encourage further investigation into the financial and environmental benefits for other imaging equipment.