Table 7.

Summarising the estimated global energy consumption and CO₂ emissions.

	Estimation Energy Consumption and CO2 emission
A guess for sufficient vaccination of the world population for one campaign (1.56 × 1010 doses [92] are required globally)
Materials Production
• Injection syringes	4.6 × 105 kWh Assumptions Electricity consumption = 1,786 kWh (Estimated based on [114] for 60 M pcs, conversion = 5.6 R/kWh [115]); 2.98 × 10−5 kWh/pcs
• Vials	4.4 × 107 kWh 7.6 × 108 MJ (2.1 × 107 kWh) Assumptions: 0.014 kWh/vials or power and 0.243 MJ/vials of natural gas [90] (1 vial is equivalent to 5 doses [113])
• Supporting material	Gloves = 1.40 × 105 kWh Shield = 1.02 × 1010 MJ (2.83 × 109 kWh) Masks = 4.68 × 107 kWh Disinfectant = 3.40 × 107 kWh Total = 1.03 × 1010 kWh Assumptions: 3 × 10−5 kWh/pair for gloves [14] 30.8 MJ/kg for shield (81 g/pcs) [14] 0.01 kWh/pcs for masks [14] The required amount of gloves, shield and masks are assumed to be 30% of the required doses, with the consideration of they are utilised in a batch and PPE is not used in all countries 2.2 × 10−3 kWh/doses for disinfectant [43]. Please refer to Table 6 for detailed assumption
Vaccination centres	1.87 × 108 kWh Assumptions: 1.2 × 10−2 kWh/doses based on [68]. Please refer to Table 6 for detailed assumption
Vaccine Manufacturing	5.2 × 105 kWh Assumptions: 3.34 kWh of power/g of vaccine [92]) (1 dose = 1 × 10−4 g of mRNA [93])
Cold supply chain	2.5 × 108 kWh Assumptions: Assume to be 69.8% share of the vaccine value chain based on Table 5.
Storage (low temp)	Assume no additional low temperature is required by sharing the existing refrigeration facilities and by dry ice accounted in the cold supply chain
Wasted resources	4.5 × 106 kWh 2.1 × 106 kWh Assumptions Assume 10% [147] vaccine dose is wasted where additional vaccine manufacturing (1.56 × 109) is required with syringe and vials
Medical waste treatment	1.3 × 108 MJ (3.7 × 107 kWh) Assumptions: 4.4 kg fuel/t. The energy density is 34.2 MJ/L 0.0832 kg is equivalent to 1 L Incineration treatment is applied (as discussed in Table 4). The weight of five dose vial = 2.517 g [186] The weight of the syringe is assumed to be 2 g. The estimation limited to the disposal of vials and syringe.
Estimated Sum (to be updated subject to the vaccination and pandemic development)	~1.08 × 1010 kWh (~5.13 × 1012 gCO2eq) for the estimated global dosage (1.56 × 1010 doses) Equivalent to ~0.69 kWh/doses (~329 gCO2eq/doses)

Note: *the global average energy conversion factor (475 gCO_2eqv/kWh) is assumed based on IEA [187]. The energy mix at a place should be applied if the sourcing and flow is known.