As sustainability reporting becomes increasingly central to Singapore’s regulatory landscape, businesses must understand the fundamentals of greenhouse gas (GHG) accounting. Scope 1 and Scope 2 emissions are defined under the GHG Protocol and adopted in ISSB/IFRS S2 Climate-related Disclosures, which guide Singapore’s emerging climate reporting requirements.
Emission Calculation Formula
Greenhouse gas emissions are commonly calculated using:
Emissions (tCO₂e) = Activity Data × Emission Factor × Global Warming Potential (if applicable)
Singapore-aligned emission factors are primarily sourced from:
✔ National Environment Agency (NEA)
✔ IPCC Guidelines (where local factors are unavailable)
Scope 1: Direct Emissions (with Example)
Scope 1 emissions arise from sources that a company owns or directly controls, including:
Fuel used in company vehicles
Diesel or natural gas burned in generators or boilers
Refrigerant leakage from cooling systems
Emissions from onsite industrial activities
Example – Company Vehicle Using Diesel
Fuel consumption: 5,000 litres of diesel
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 (with Example)
Scope 2 emissions cover indirect GHG emissions from purchased electricity, steam, heating, or cooling. In Singapore, the main component is grid electricity consumption.
Example – Office Electricity Use
Annual electricity consumption: 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
Understanding how to classify and calculate Scopes 1 and 2 is essential for compliance, credibility, and effective sustainability management. If your organisation requires guidance in emissions measurement or reporting, our team is ready to support you.