GHG Protocol Reporting Software for Scope 1, 2 & 3 Emissions
Calculate, track, and report Scope 1, 2, and 3 emissions using GHG Protocol methodology. Horizon ESG handles the complexity of carbon accounting so you can focus on reduction.
Complete GHG Protocol Coverage
From direct emissions to value chain – every scope, every category, every calculation.
Scope 1 Emissions
Automatic calculation of direct emissions from owned operations, fuel combustion, and refrigerant leaks.
Scope 2 Emissions
Location-based and market-based calculations with grid emission factors and renewable energy certificates.
Scope 3 Categories
All 15 upstream and downstream categories with spend-based, activity-based, and hybrid calculation methods.
Emission Factors
Built-in DEFRA, EPA, IPCC, and ecoinvent factors – automatically updated each year.
Reduction Tracking
Set absolute and intensity targets, model reduction pathways, and track year-on-year progress.
Verification Ready
ISO 14064-aligned outputs with complete audit trails for third-party verification.
What Are Scope 1, 2 and 3 Emissions?
The GHG Protocol Corporate Standard divides emissions into three scopes, each requiring different data sources and calculation approaches.
Scope 1: Direct Emissions
Emissions from sources your organisation owns or controls directly, including company vehicles, on-site boilers, and fugitive emissions from refrigerants.
Scope 2: Indirect Energy
Indirect emissions from purchased electricity, heat, steam, and cooling, reported using both location-based and market-based methods.
Scope 3: Value Chain
All other indirect emissions across your value chain, typically 70-90% of total footprint, covering all 15 GHG Protocol categories.
How the GHG Protocol Categorises Emissions
The GHG Protocol Corporate Standard divides emissions into three scopes, each requiring different data sources, calculation approaches, and levels of organisational control. GHG Protocol reporting software must handle all three comprehensively.
Scope 1: Direct Emissions
Scope 1 covers emissions from sources your organisation owns or controls directly. This includes combustion of fuels in company vehicles, on-site boilers and furnaces, fugitive emissions from refrigerants, and process emissions from manufacturing. A GHG Protocol tool automates these calculations using fuel consumption data and equipment specifications.
Scope 2: Indirect Energy Emissions
Scope 2 covers indirect emissions from purchased electricity, heat, steam, and cooling. The GHG Protocol requires reporting using both the location-based method, which uses grid-average emission factors, and the market-based method, which accounts for renewable energy procurement through instruments like REGOs and GOs. Platforms differ in how thoroughly they implement this, which our comparison of ESG reporting software covers in detail. GHG Protocol reporting software applies both methodologies automatically based on your energy procurement data.
Scope 3: Value Chain Emissions
Scope 3 encompasses all other indirect emissions across your value chain, typically representing 70 to 90 percent of a company’s total carbon footprint. The GHG Protocol Corporate Value Chain Standard identifies 15 categories including purchased goods and services, business travel, employee commuting, upstream and downstream transportation, and end-of-life treatment of products. Comprehensive carbon emissions reporting requires a GHG Protocol tool capable of handling multiple calculation methodologies across all 15 categories.
Emission Factors and Calculation Methodologies
Accurate carbon emissions reporting depends on using the correct emission factors and calculation methodologies. GHG Protocol reporting software must maintain an up-to-date library of verified factors and support multiple approaches to calculation.
- DEFRA/BEIS factors: the UK Government publishes annual greenhouse gas reporting conversion factors used for SECR, CDP, and voluntary disclosures. Your GHG Protocol tool should update these automatically each year.
- IEA emission factors: the International Energy Agency provides country-specific grid electricity emission factors used for international Scope 2 calculations.
- EPA factors: for organisations with US operations, EPA emission factors are the standard reference for federal reporting programmes.
- Spend-based vs activity-based: Scope 3 calculations can use spend-based methods using economic input-output models, or activity-based methods using specific quantities and supplier data. The best GHG Protocol reporting software supports both and helps you transition from spend-based to activity-based as data availability improves.
- Supplier-specific factors: as supply chain data improves, using actual emission factors provided by suppliers delivers more accurate Scope 3 inventories than generic industry averages.
How Horizon ESG Automates GHG Protocol Reporting
Horizon ESG is GHG Protocol reporting software that turns raw activity data into auditable carbon inventories. Our carbon accounting platform handles the full GHG Protocol workflow from data collection through to disclosure.
- Automated data ingestion: our AI engine extracts emissions-relevant data from invoices, utility bills, travel records, and procurement systems, eliminating manual data entry.
- Verified emission factor library: DEFRA, IEA, EPA, and custom supplier-specific factors are maintained and updated automatically within the platform.
- All 15 Scope 3 categories: calculate emissions across every Scope 3 category using spend-based, activity-based, or hybrid methodologies as your data matures.
- Dual Scope 2 reporting: automatic location-based and market-based calculations with support for renewable energy certificates and power purchase agreements.
- Year-on-year tracking: monitor emissions trends, track progress against reduction targets, and identify hotspots across your operations and value chain.
- Multi-framework output: your GHG inventory feeds directly into CSRD, TCFD, CDP, SECR, and GRI disclosures without re-entering data or reconciling separate calculations.
Frequently Asked Questions
What is GHG Protocol reporting software?
GHG Protocol reporting software is a platform that automates the calculation and reporting of greenhouse gas emissions in accordance with the GHG Protocol Corporate Standard and Corporate Value Chain Standard. It manages emission factors, supports all three scopes, and produces disclosures suitable for regulatory submissions, investor reports, and CDP questionnaires.
Do I need to report Scope 3 emissions?
Scope 3 reporting is required under CSRD/ESRS, expected by CDP, and increasingly demanded by investors and supply chain partners. Even if not yet mandatory for your organisation, Scope 3 represents the majority of most companies’ carbon footprint and is essential for credible climate targets. GHG Protocol reporting software makes Scope 3 manageable by automating calculations across all 15 categories.
Which emission factors does Horizon ESG use?
Horizon ESG maintains a comprehensive library of emission factors including DEFRA/BEIS (UK), IEA (international), EPA (US), and ecoinvent databases. The platform also supports custom supplier-specific factors. All factor libraries are updated automatically when new versions are released by the governing bodies.
Can GHG Protocol reporting software help set science-based targets?
Yes. By providing a complete and accurate GHG inventory across all three scopes, GHG Protocol reporting software gives you the baseline data needed to set science-based targets aligned with SBTi methodologies. Horizon ESG also tracks your progress against those targets over time, helping you demonstrate credible climate action to stakeholders.
Further Reading
Start your carbon accounting journey
Horizon ESG makes GHG Protocol reporting accurate, automated, and auditable. From Scope 1 through Scope 3, our carbon accounting platform gives your team the tools to measure, reduce, and report emissions with confidence.
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All fifteen Scope 3 categories
See the calculation methodology and the factor sources behind each one.
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