As sustainability reporting becomes mandatory in Singapore, organisations must clearly understand how to classify and measure greenhouse gas (GHG) emissions under internationally recognised standards. The definitions of Scope 1 and Scope 2 are derived from the GHG Protocol and adopted in ISSB/IFRS S2 Climate-related Disclosures, which underpin Singapore’s climate reporting framework.
Emission Calculation Formula
GHG emissions are commonly calculated using the following formula:
Emissions (tCO₂e) = Activity Data × Emission Factor × Global Warming Potential (if applicable)
Singapore-recommended emission factors are typically sourced from:
National Environment Agency (NEA)
IPCC (where local factors are unavailable)
Scope 1: Direct Emissions
Scope 1 emissions refer to direct GHG emissions from sources owned or controlled by the organisation. Examples include:
Fuel combustion from company-owned vehicles
Diesel or natural gas used in generators or boilers
Refrigerant leakage from air-conditioning systems
Onsite industrial process emissions
Example – Diesel Vehicle
Annual diesel usage: 5,000 litres
Emission factor: 2.68 kg CO₂e per litre
Emissions = 5,000 × 2.68 = 13,400 kg CO₂e
= 13.4 tCO₂e
Scope 2: Indirect Energy Emissions
Scope 2 emissions cover indirect GHG emissions from purchased electricity, steam, heating or cooling consumed by the organisation. In Singapore, this primarily relates to grid electricity used in offices, warehouses, and factories.
Example – Electricity Consumption
Annual electricity use: 50,000 kWh
Singapore grid emission factor: 0.408 kg CO₂e per kWh
Emissions = 50,000 × 0.408 = 20,400 kg CO₂e
= 20.4 tCO₂e
Accurately identifying and quantifying emissions is essential for meeting Singapore’s climate reporting requirements and demonstrating environmental accountability. If your organisation requires support in emissions measurement or reporting, our team is ready to assist.