Greenhouse Gas (GHG

Corporate Sustainability & ESG Reporting: The GHG Protocol Scopes

The Greenhouse Gas Protocol Corporate Standard provides the foundation for SEC climate disclosures, CDP reporting, and Science Based Targets (SBTi):

• Scope 1 (Direct GHG Emissions): Occur from sources owned or controlled by the company (industrial manufacturing boilers, emergency diesel backup generators, and company-owned vehicle fleets).

• Scope 2 Dual-Reporting Standard (Location vs. Market-Based):

• Location-Based: Reflects average emissions intensity of the regional power grid where electricity is consumed.

• Market-Based: Accounts for specific contractual choices, such as Power Purchase Agreements (PPAs), green tariffs, and unbundled Renewable Energy Certificates (RECs).

• Scope 3: Encompasses 15 distinct upstream and downstream categories, including purchased goods and services, capital goods, employee commuting, and business travel.

How to Use This Calculator

Enter your Scope 1: Stationary Natural Gas/Fuel Combustion (MMBTU/Year) (e.g. 5,000 (Facility boilers & furnaces)), Scope 1: Company Fleet Fuel (Gallons/Year) (e.g. 10,000 (Diesel & gasoline fleet)), Scope 2: Purchased Electricity (MWh/Year) (e.g. 1,200 (1,200 MWh = 1,200,000 kWh)), Scope 2: Certified Renewable Energy / REC Match (%) (e.g. 40 (40% green power purchasing for market-based method)), Scope 3: Purchased Goods & Services Supply Chain Spend (e.g. 500,000), and Scope 3: Commercial Airline Business Travel (Miles/Year) (e.g. 150,000). Results update instantly as you type — adjust any value to compare scenarios.

The Formula

GHG Protocol Corporate Standard & ISO 14064 Accounting equations:

Scope 1 (tCO_2e) = (MMBTU × 0.05306) + (Fleet Gallons × 0.008887)

Scope 2 Location-Based = Purchased MWh × 0.386 tCO_2e/MWh

Scope 2 Market-Based = Purchased MWh × (1 - REC %) × 0.386

Scope 3 Value Chain = (Spend × 0.00035) + (Flight Miles × 0.000155)

Total Market-Based GHG Inventory = Scope 1 + Scope 2 (Market) + Scope 3

Worked Example

For example, an enterprise consuming 5,000 MMBTU of natural gas (265.30 tCO_2e), 10,000 gallons fleet diesel (88.87 tCO_2e), purchasing 1,200 MWh electricity with 40% green RECs (277.92 tCO_2e market-based), 500,000 supply chain spend (175.0 t), and 150,000 flight miles (23.25 t): Scope 1 is 354.17 tCO2e (42.6%), Scope 2 is 277.92 tCO2e (33.5%), and Scope 3 is 198.25 tCO2e (23.9%). Total Market-Based Carbon Inventory is 830.34 Metric Tonnes CO2e/year (saving 185.28 tCO2e via green power RECs).

Understanding Your Result

US EPA fuel economy benchmarks (2024): Compact cars 28–35 MPG combined; midsize SUVs 22–28 MPG; pickup trucks 16–22 MPG; hybrid vehicles 40–55 MPG; EVs equivalent 90–120 MPGe. At 3.50/gallon, every 1 MPG improvement saves approximately 35–50/year over 10,000–15,000 annual miles. Real-world fuel economy typically runs 15–20% below EPA ratings in stop-and-go traffic, cold weather (reduces efficiency 15–25%), or with heavy loads.