Table 2.
Transportation-related greenhouse gas emissions associated with total short-course versus long-course radiation therapy treatment by primary emission gas and vehicle type and converted to CO2 equivalents by global warming potential
| Emission | Gas | Hybrid | PHEV | Electric | Emissions, kg | GWP | Emissions, CO2e, kg |
|---|---|---|---|---|---|---|---|
| Short course | |||||||
| VOCs | 0.08 | 0.00 | 0.00 | 0.01 | 0.09 | Not defined | - |
| CO | 0.79 | 0.06 | 0.01 | 3.09 | 3.94 | Not defined | - |
| N2O | 0.11 | 0.01 | 0.00 | 0.00 | 0.11 | Not defined | - |
| CH4 | 0.13 | 0.01 | 0.00 | 0.01 | 0.14 | 28.00 | 3.9 |
| CO2 | 122.94 | 7.13 | 1.33 | 3.09 | 134.49 | 1.00 | 134.5 |
| NO2 | 0.04 | 0.00 | 0.00 | 0.00 | 0.04 | 298.00 | 11.4 |
| Total CO2e emissions | - | - | - | - | - | - | 149.9 |
| Long course | |||||||
| VOCs | 0.35 | 0.02 | 0.00 | 0.03 | 0.40 | Not defined | - |
| CO | 3.49 | 0.27 | 0.03 | 13.71 | 17.51 | Not defined | - |
| N2O | 0.48 | 0.03 | 0.00 | 0.00 | 0.51 | Not defined | - |
| CH4 | 0.56 | 0.03 | 0.01 | 0.03 | 0.63 | 28.00 | 17.6 |
| CO2 | 545.71 | 31.66 | 5.92 | 13.71 | 597.00 | 1.00 | 597.0 |
| NO2 | 0.16 | 0.01 | 0.00 | 0.00 | 0.17 | 298.00 | 50.7 |
| Total CO2e emissions | - | - | - | - | - | - | 665.3 |
Abbreviations: CH4 = methane; CO = carbon monoxide; CO2 = carbon dioxide; CO2e = carbon dioxide equivalents; GWP = global warming potential; N2O = nitrous oxide; NO2 = nitrogen dioxide; PHEV = plug-in-hybrid electric vehicle; VOCs = volatile organic compounds.