Table 2. CO2 emission factors.
Emission factors used for calculations in all relevant categories including the respective sources.
| Category | CO2 emission factor | Reference |
|---|---|---|
| Transportation | ||
| Airplane | 101.3 g/RPK | EPA (2022) |
| Car | 130.3 g/km | EEA (2022) |
| Train | 64 g/km | Zheng (2022) |
| Public transport | 199 g/km | EPA (2022) |
| Food | ||
| Rice/potatoes | 2,455 g/kg | Ritchie, Rosado & Roser (2022) |
| Vegetables | 980 g/kg | Ritchie, Rosado & Roser (2022) |
| Cheese/eggs | 14,274 g/kg | Ritchie, Rosado & Roser (2022) |
| Milk | 3,150 g/kg | Ritchie, Rosado & Roser (2022) |
| Coffee/tea | 28,530 g/kg | Ritchie, Rosado & Roser (2022) |
| Wine | 1,790 g/kg | Ritchie, Rosado & Roser (2022) |
| Beer | 500 g/pint | Berners-Lee (2010) |
| 1.5 l glass water bottles | 323 g/bottle | Tappwater (2022) |
| Accommodation | ||
| Night/three-star hotel | 16,900 g | Ratjen (2016) |
| Energy | ||
| Norwegian hydropower | 3.33 g/kWh | Silva & Saur Modahl (2015) |
| Tapwater (sanitary use) | 468 g/kWh | Meunier (2020) |
| Wastewater | 290 g/m3 | Wang et al. (2016) |
| Household waste | 500 g/kg | BEHG (2020) |
| Online attendance | 10,000 g/attendee | Strüber (2021) |
| Additional items | ||
| T-shirts | 8,300 g/t-shirt | Khan & Islam (2015) |
| Conference pass | 6 g/pass | Ezeep (2022) |
| Lanyards | 2,700 g/kg | WePrintLanyards (2022) |
Notes.
*RPK, Revenue passenger kilometre.
*EPA, United States Environmental Protection Agency.
*EEA, European Environment Agency.
*BEHG, Brennstoff-Emissionshandelsgesetz (Germany).