Overview
What are Custom Emission Factors?
Custom emission factors are user-defined emission values that override Dcycle’s standard database factors for specific products, services, or processes. They are organized into Custom Emission Groups (categories) and can be applied to:- Purchases - Supplier-specific product emission factors
- Wastes - Custom waste treatment emission factors
- Energy - Renewable energy with specific grid mix data
When to Use Custom Factors
✅ Use custom factors when:- You have supplier-provided LCA data with verified emission factors
- Your product/service has unique characteristics not captured by standard factors
- You need to track specific renewable energy contracts (PPAs)
- Regulatory requirements demand specific calculation methodologies
- Standard Dcycle factors are available and appropriate
- You’re guessing or estimating without verified data
- You want to artificially lower your emissions (greenwashing)
Workflow
1
Create Custom Emission Group
First, create a group (category) to organize your custom factors
2
Add Custom Emission Factors
Add individual emission factors to the group
3
Use in Purchases/Wastes
Reference your custom factor when creating purchases or wastes
4
Monitor & Update
Review and update factors annually or when supplier data changes
Data Structure
Custom Emission Group
A group organizes related custom emission factors:Custom Emission Factor
An individual factor within a group:Gas Types
Custom factors can include multiple greenhouse gases:Dcycle automatically converts all gases to CO2 equivalent (CO2e) using IPCC AR6 Global Warming Potential values.
Categories
Custom emission factors are organized by category:Purchases (purchases)
- Supplier-specific product emission factors
- Custom service emission calculations
- Industry-specific materials
Wastes (wastes)
- Custom waste treatment emission factors
- Specific disposal method emissions
- Regional waste processing differences
Energy (energy)
- Renewable energy contracts with specific grid mix
- Power Purchase Agreements (PPAs)
- On-site generation (solar, wind)
Uncertainty Grades
Track the confidence level of your custom factors:Best Practices
1. Document Everything
Always document the source and methodology:2. Set Validity Periods
Update factors regularly:3. Include All GHGs
Don’t just use CO2 - include CH4, N2O when available:4. Use Appropriate Units
Match units to your usage:- Mass-based: kg, ton (for solid materials)
- Volume-based: L, m³ (for liquids, gases)
- Energy-based: kWh, MJ (for energy products)
- Currency-based: EUR, USD (as last resort)
5. Tag Complexity Appropriately
- Simple tag: Basic single-value factors
- Advanced tag: Multi-gas, time-variant, or complex calculations
Validation Requirements
Dcycle validates custom factors to ensure data quality:Required Fields
- ✅ Emission factor name (
ef_name) - ✅ Unit ID (
unit_id) - ✅ At least one emission value (CO2 minimum)
- ✅ Uploaded by reference (
factor_uploaded_by) - ✅ Tag (
simpleoradvanced)
Optional but Recommended
- 📝 Uncertainty grade (0-100%)
- 📝 Validity period (start/end dates)
- 📝 Documentation reference (
additional_docs) - 📝 Additional gases (CH4, N2O)
Automatic Checks
- ⚠️ Values must be non-negative
- ⚠️ Uncertainty grade must be 0-100%
- ⚠️ End date must be after start date
- ⚠️ Gas types must be valid (CO2, CH4, N2O, etc.)
API Endpoints
Create Factor
Add new custom emission factor
List Factors
View factors in a group
Get Factor
Retrieve specific factor details
Update Factor
Modify existing factor
Delete Factor
Remove custom factor
Manage Groups
Create and organize groups
Common Use Cases
Supplier-Specific Product Factors
When a supplier provides EPD (Environmental Product Declaration) data:Renewable Energy PPA
For Power Purchase Agreements with specific renewable sources:Custom Waste Treatment
For facility-specific waste treatment emissions:Related Documentation
Custom Emission Groups
Organize custom factors into groups
Purchases
Use custom factors in purchases
Wastes
Apply to waste management
Units
Available measurement units