Core Concepts

Understanding these fundamental concepts will help you use the Dcycle API effectively and interpret your emissions data correctly.

Carbon Accounting Basics

What is CO2 Equivalent (CO2e)?

CO2 equivalent (CO2e) is a standardized metric that allows different greenhouse gases to be compared on a common scale. Not all greenhouse gases have the same warming effect. For example:

1 kg of Methane (CH4) = 28 kg CO2e
1 kg of Nitrous Oxide (N2O) = 265 kg CO2e
1 kg of SF6 = 23,500 kg CO2e

Dcycle automatically converts all gases to CO2e using IPCC AR6 Global Warming Potential (GWP) values over a 100-year timeframe.

Example Calculation

# Manual calculation
ch4_emissions = 10  # kg of methane
gwp_ch4 = 28  # AR6 100-year GWP

co2e = ch4_emissions * gwp_ch4
# Result: 280 kg CO2e

# Dcycle does this automatically
response = api.calculate_emissions(
    methane=10,
    # Returns: {"co2e": 280, "breakdown": {...}}
)

Emission Scopes

The GHG Protocol divides emissions into three scopes to help organizations understand their carbon footprint:

Scope 1: Direct Emissions

Emissions from sources owned or controlled by your organization. Examples:

Company-owned vehicles (fleet)
On-site fuel combustion (boilers, generators)
Manufacturing processes
Fugitive emissions (refrigerants, leaks)

# Track Scope 1 with Dcycle
# Fleet emissions
vehicle_emissions = api.track_vehicle_consumption(...)

# Facility fuel combustion
facility_emissions = api.track_facility_fuel(...)

Scope 2: Indirect Energy Emissions

Emissions from purchased electricity, heating, or cooling. Examples:

Electricity consumption in offices
District heating/cooling
Purchased steam

# Track Scope 2 with Dcycle
# Upload utility invoices
invoice_emissions = api.upload_invoice(
    type="electricity",
    consumption=5000,  # kWh
    period="2024-01"
)

Scope 3: Other Indirect Emissions

All other indirect emissions in your value chain. Examples:

Upstream: Purchased goods, business travel, employee commuting, waste disposal
Downstream: Product transportation, end-of-life treatment, franchises

# Track Scope 3 with Dcycle
# Purchased goods
purchase_emissions = api.track_purchases(...)

# Logistics (upstream/downstream)
shipment_emissions = api.calculate_shipment(...)

# Waste disposal
waste_emissions = api.track_waste(...)

Scope Summary

Scope 1

Direct emissionsYou own and control the source

Scope 2

Energy indirectYou purchase the energy

Scope 3

Other indirectYour value chain

Emission Factors

An emission factor is a coefficient that quantifies emissions per unit of activity.

What is an Emission Factor?

Emissions = Activity Data × Emission Factor

Example:

Diesel consumption: 100 liters
Emission factor: 2.68 kg CO2e/liter
Total emissions: 100 × 2.68 = 268 kg CO2e

Types of Emission Factors

Standard Factors

Pre-calculated factors from databases like DEFRA, ADEME, or EPA.Used for: Generic activities without specific supplier dataAccuracy: Medium to High (depends on database quality)Example: “Diesel fuel combustion” = 2.68 kg CO2e/liter

Spend-Based Factors

Factors based on monetary value ($/€ spent).Used for: When physical data is unavailableAccuracy: Low (high uncertainty)Example: “IT services” = 0.15 kg CO2e/€

Custom Emission Factors

Supplier-specific factors from EPDs or LCA studies.Used for: Supplier-verified data, PPAs, specific processesAccuracy: Very High (supplier-verified)Example: “Recycled aluminum - Supplier ABC” = 2.15 kg CO2e/kgSee the Custom Emission Factors guide for details.

Dcycle’s Emission Factor Database

Dcycle maintains an extensive database with:

15,000+ emission factors
50+ countries
Multiple methodologies (DEFRA, ADEME, EPA, GHG Protocol)
Regular updates following latest IPCC guidelines

ISO 14083 Standard

ISO 14083 is the international standard for quantifying and reporting greenhouse gas emissions from transport operations.

Key Principles

Well-to-Wheel (WTW) Methodology

Includes both fuel production (Well-to-Tank) and vehicle operation (Tank-to-Wheel).

Total Emissions = WTT Emissions + TTW Emissions

Distance-Based Calculation

Emissions = Distance × Load × Emission FactorAccounts for both empty and loaded trips.

Transport Chain Allocation

For shipments with multiple legs (truck → ship → truck), emissions are allocated proportionally.

Default Values

When specific data is unavailable, ISO 14083 provides default load factors and emission factors.

Example: ISO 14083 Calculation

# Dcycle automatically follows ISO 14083
response = api.calculate_shipment(
    origin="Madrid, Spain",
    destination="Barcelona, Spain",
    toc="van_diesel",  # Transport Operation Category
    load=1000,
    load_unit="kg",
    year=2024
)

# Response includes ISO 14083 breakdown
{
    "co2e": 245.5,  # Total WTW emissions
    "distance_km": 620.0,
    "methodology": "ISO 14083",
    "breakdown": {
        "ttw": 215.3,  # Tank-to-Wheel (direct)
        "wtw": 30.2    # Well-to-Tank (upstream)
    }
}

Transport Operation Categories (TOC)

ISO 14083 defines standard vehicle categories:

Category	Description	Example
Van	Light commercial vehicle	Delivery van
Rigid	Single-unit truck	Box truck
Articulated	Tractor-trailer	Semi-truck
Rail	Freight train	Container train
Maritime	Cargo ship	Container vessel
Air	Cargo aircraft	Freight plane

GHG Protocol

The Greenhouse Gas Protocol is the most widely used international accounting standard for greenhouse gas emissions.

Core Principles

Relevance: Report emissions appropriate to the organization’s needs
Completeness: Include all emission sources within boundaries
Consistency: Use consistent methodologies for comparisons
Transparency: Document assumptions and data sources
Accuracy: Reduce uncertainties as much as possible

Organizational Boundaries

Equity Share

Account for emissions based on % ownership

Operational Control

Account for 100% of emissions from controlled operations

Financial Control

Account for operations with financial control

Uncertainty and Data Quality

Not all emissions data is equally accurate. Understanding uncertainty helps prioritize data improvement efforts.

Data Quality Hierarchy

1. Primary Data (Measured)           ← Highest accuracy
   └─ Direct measurements, supplier EPDs

2. Secondary Data (Calculated)
   └─ Standard emission factors, industry averages

3. Tertiary Data (Estimated)
   └─ Spend-based factors, proxies

4. Extrapolated Data (Assumed)      ← Lowest accuracy
   └─ Historical trends, benchmarks

Reducing Uncertainty

Start with what you have

Use spend-based factors to establish baseline

Collect primary data

Gather utility bills, fuel receipts, supplier data

Request supplier-specific factors

Ask suppliers for EPDs or product carbon footprints

Use custom emission factors

Replace generic factors with verified supplier data

Uncertainty Grades in Dcycle

When using custom emission factors, track uncertainty:

custom_factor = {
    "ef_name": "Supplier ABC Aluminum",
    "uncertainty_grade": 15,  # 15% uncertainty (high confidence)
    "additional_docs": "EPD No. ABC-2024-001, Bureau Veritas verified",
    # ...
}

# Track data quality over time
# Prioritize improving factors with >50% uncertainty

Biogenic vs. Fossil Emissions

Different carbon sources have different climate impacts.

Fossil Emissions

Carbon from underground reserves (oil, gas, coal). Impact: Adds NEW carbon to atmosphere Reporting: Always included in total emissions Example: Diesel fuel, natural gas

Biogenic Emissions

Carbon from biomass (wood, crops, organic waste). Impact: Part of natural carbon cycle (carbon was recently in atmosphere) Reporting: Often reported separately Example: Biogas, biomass burning, composting

Why It Matters

# Waste treatment example
landfill_methane = {
    "source": "organic_waste",
    "ch4_emissions": 10,  # kg
    "type": "biogenic"     # Was recently atmospheric CO2
}

diesel_combustion = {
    "source": "fossil_fuel",
    "co2_emissions": 268,  # kg
    "type": "fossil"       # New atmospheric carbon
}

Dcycle tracks biogenic and fossil emissions separately when relevant (e.g., waste management, energy from biomass).

Next Steps

Now that you understand the core concepts, explore how to apply them:

Calculate Emissions

Learn how to calculate emissions for different activities

Custom Emission Factors

Use supplier-specific data for accurate tracking

Quickstart

Make your first API call

API Reference

Explore all available endpoints

Introduction

Core Concepts

Support

​Core Concepts

​Carbon Accounting Basics

​What is CO2 Equivalent (CO2e)?

​Example Calculation

​Emission Scopes

​Scope 1: Direct Emissions

​Scope 2: Indirect Energy Emissions

​Scope 3: Other Indirect Emissions

​Scope Summary

Scope 1

Scope 2

Scope 3

​Emission Factors

​What is an Emission Factor?

​Types of Emission Factors

​Dcycle’s Emission Factor Database

​ISO 14083 Standard

​Key Principles

​Example: ISO 14083 Calculation

​Transport Operation Categories (TOC)

​GHG Protocol

​Core Principles

​Organizational Boundaries

Equity Share

Operational Control

Financial Control

​Uncertainty and Data Quality

​Data Quality Hierarchy

​Reducing Uncertainty

​Uncertainty Grades in Dcycle

​Biogenic vs. Fossil Emissions

​Fossil Emissions

​Biogenic Emissions

​Why It Matters

​Next Steps

Calculate Emissions

Custom Emission Factors

Quickstart

API Reference

Core Concepts

Carbon Accounting Basics

What is CO2 Equivalent (CO2e)?

Example Calculation

Emission Scopes

Scope 1: Direct Emissions

Scope 2: Indirect Energy Emissions

Scope 3: Other Indirect Emissions

Scope Summary

Emission Factors

What is an Emission Factor?

Types of Emission Factors

Dcycle’s Emission Factor Database

ISO 14083 Standard

Key Principles

Example: ISO 14083 Calculation

Transport Operation Categories (TOC)

GHG Protocol

Core Principles

Organizational Boundaries

Uncertainty and Data Quality

Data Quality Hierarchy

Reducing Uncertainty

Uncertainty Grades in Dcycle

Biogenic vs. Fossil Emissions

Fossil Emissions

Biogenic Emissions

Why It Matters

Next Steps