For a typical 30 m² office equipped with a modern split (SEER 8) in France, the calculation has 3 stages. Consumption is around 500 kWh per 4-month season. Electricity emits 500 kWh × 30 gCO2e/kWh (France mix, RTE 2024), or 15 kgCO2e/year. Leaks add more: a split this size contains around 1 kg of R32, and at 5% leakage per year, 0.05 kg × 675 gives 30 to 35 kgCO2e/year. The total is around 45 to 50 kgCO2e/year per unit, with 2 thirds due to leaks. Multiply by 4 to 8 for an office with 25 people. The same installation in Germany (mix of around 380 gCO2e/kWh) would emit 190 kgCO2e/year from electricity alone.
Read the source article: What is the environmental impact of air conditioning?