S3. Category 1: Purchased Goods and Services

Understanding Scope 3 Category 1

Purchased goods and services emissions are indirect greenhouse gas emissions from the extraction, production, and transportation of goods and services acquired by your organization. According to the GHG Protocol Scope 3 Standard, Category 1 typically represents:

Raw materials: Metals, plastics, chemicals, wood, textiles
Intermediate products: Components, parts, packaging materials
Services: Professional services, IT services, maintenance, consulting

┌─────────────────────────────────────────────────────────────────────────────┐
│                    SCOPE 3 CATEGORY 1: Purchased Goods & Services           │
├─────────────────────┬─────────────────────┬─────────────────────────────────┤
│  Raw Materials      │  Intermediate       │  Services                       │
│                     │  Products           │                                 │
├─────────────────────┼─────────────────────┼─────────────────────────────────┤
│  • Metals           │  • Components       │  • IT services                  │
│  • Plastics         │  • Packaging        │  • Professional services        │
│  • Chemicals        │  • Semi-finished    │  • Maintenance                  │
│  • Textiles         │  • Electronics      │  • Consulting                   │
└─────────────────────┴─────────────────────┴─────────────────────────────────┘

Why Category 1 MattersFor most organizations, purchased goods and services represent 40-80% of total emissions. This makes Category 1 the single most important area for understanding and reducing your carbon footprint.Typical Category 1 Contribution:

Manufacturing: 60-80% of Scope 3
Retail: 70-90% of Scope 3
Services: 30-50% of Scope 3

Prerequisites

Before starting, ensure you have:

Dcycle API credentials (get them here)
Purchase data: invoices, procurement records, or ERP exports
Knowledge of your spending categories (for spend-based method) or physical quantities (for activity-based method)

Using the Dcycle App?You can also manage purchases through our web interface:

Upload purchases manually (ES) - Individual purchase tracking
Upload purchases automatically (ES) - Bulk import from ERP

Data Map: Purchased Goods & Services Requirements Overview

Before diving into the calculations, here’s a complete overview of the data you’ll need:

┌─────────────────────────────────────────────────────────────────────────────────────────┐
│                   PURCHASED GOODS & SERVICES DATA REQUIREMENTS                          │
├─────────────────────────────────────────────────────────────────────────────────────────┤
│                                                                                         │
│  ┌─────────────────────────────────────────────────────────────────────────────────┐   │
│  │ SUPPLIER SETUP (Step 4.1)                                                       │   │
│  ├─────────────────────────────────────────────────────────────────────────────────┤   │
│  │                                                                                 │   │
│  │  Required Fields           Optional Fields           For Custom EFs            │   │
│  │  ─────────────────         ───────────────           ─────────────────         │   │
│  │  • business_name           • contact_email           • EPD reference           │   │
│  │  • country                 • sector                  • Certification           │   │
│  │  • tax_id                  • supplier_code           • Verification date       │   │
│  │                                                                                 │   │
│  └─────────────────────────────────────────────────────────────────────────────────┘   │
│                                                                                         │
│  ┌─────────────────────────────────────────────────────────────────────────────────┐   │
│  │ PURCHASE DATA (Steps 4.2 - 4.4)                                                 │   │
│  ├─────────────────────────────────────────────────────────────────────────────────┤   │
│  │                                                                                 │   │
│  │  Spend-Based               Activity-Based            Supplier-Specific         │   │
│  │  ────────────────────      ────────────────          ─────────────────         │   │
│  │  • quantity (€)            • quantity (kg, units)    • quantity                │   │
│  │  • unit_id (€)             • unit_id (kg, m³, etc.)  • unit_id                 │   │
│  │  • sector                  • product_name            • custom_emission_        │   │
│  │  • product_name            • sector                    factor_id               │   │
│  │  • country                 • country                 • supplier_id             │   │
│  │  • purchase_date           • purchase_date           • purchase_date           │   │
│  │                            • supplier_id             • recycled (%)            │   │
│  │                                                                                 │   │
│  └─────────────────────────────────────────────────────────────────────────────────┘   │
│                                                                                         │
└─────────────────────────────────────────────────────────────────────────────────────────┘

Calculation Methods

Dcycle supports three calculation methods for purchased goods and services, each with different accuracy levels:

Data Quality Hierarchy

┌────────────────────────────────────────────────────────────────────────────────────────┐
│                            DATA QUALITY HIERARCHY                                       │
├────────────────────────────────────────────────────────────────────────────────────────┤
│                                                                                        │
│  Level 1: Supplier-Specific Data ─────────────────────────────────── HIGHEST ACCURACY │
│  ├─ EPDs, Product Carbon Footprints, Supplier PCFs                                    │
│  ├─ Accuracy: ±5-15%                                                                  │
│  └─ Use: custom_emission_factor_id                                                    │
│                                                                                        │
│  Level 2: Activity-Based Data ─────────────────────────────────────── MEDIUM ACCURACY │
│  ├─ Product category + physical quantity (kg, m³, units)                              │
│  ├─ Accuracy: ±20-40%                                                                 │
│  └─ Use: quantity + unit_id + sector/product_name                                     │
│                                                                                        │
│  Level 3: Spend-Based Data ─────────────────────────────────────────── LOWER ACCURACY │
│  ├─ Only monetary value + category                                                    │
│  ├─ Accuracy: ±50-100%                                                                │
│  └─ Use: quantity (€) + unit_id (€) + sector/product_name                             │
│                                                                                        │
└────────────────────────────────────────────────────────────────────────────────────────┘

Spend-Based Method
Activity-Based Method
Supplier-Specific Method

The spend-based method uses economic input-output (EEIO) emission factors based on the monetary value of purchases.

Spend (€) → Sector/Product Category → Exiobase EF → CO₂e
     ↓              ↓                      ↓           ↓
Invoice amount   Product mapping      kg CO₂e/€    Total emissions

Key characteristics:

Uses Exiobase 3.8.2 input-output emission factors
Emission factors in kg CO₂e per € (or other currency)
Covers all economic sectors and product categories
Lower accuracy but broad coverage

Emission Factor Sources - Spend-Based

For spend-based calculations, Dcycle uses emission factors from:

Exiobase 3.8.2 - Multi-Regional Environmentally Extended Supply-Use Tables
Covers 44 countries and 200+ product categories
Source: Exiobase

Factors are automatically selected based on:

Sector/product category
Supplier country (or your organization’s country)
Purchase year

Calculation Details - Spend-Based

Spend-based emissions are calculated as:CO₂e = Spend Amount (€) × Economic Intensity Factor (kg CO₂e/€)Where:

Spend Amount: Monetary value of the purchase
Economic Intensity Factor: Exiobase emission factor for the sector/product

Example (IT Services):

€15,000 × 0.15 kg CO₂e/€ = 2,250 kg CO₂e

Note: Spend-based factors have high uncertainty (±50-100%) and should be used when physical quantities are unavailable.

The activity-based method uses physical quantities and product-specific emission factors.

Quantity (kg) → Product Category → Activity-Based EF → CO₂e
      ↓               ↓                    ↓              ↓
Physical amount   Product type        kg CO₂e/kg     Total emissions

Key characteristics:

Uses physical quantities (mass, volume, units)
More accurate than spend-based
Requires detailed procurement data
Better for tracking reduction efforts

Emission Factor Sources - Activity-Based

For activity-based calculations, Dcycle uses emission factors from:

Ecoinvent - Life cycle inventory database (latest version available)
Industry-specific databases - Sector-specific factors
Covers materials, components, and products

Factors are automatically selected based on:

Product name/category
Material type
Country of origin

Calculation Details - Activity-Based

Activity-based emissions are calculated as:CO₂e = Quantity × Emission Factor (kg CO₂e/unit)Where:

Quantity: Physical amount (kg, m³, units, etc.)
Emission Factor: Product-specific factor from database

Example (Aluminum sheets):

1,000 kg × 8.5 kg CO₂e/kg = 8,500 kg CO₂e

Note: Activity-based is 2-3× more accurate than spend-based.

The supplier-specific method uses verified emission data from your suppliers (EPDs, PCFs).

Quantity → Supplier EPD/PCF → Verified EF → CO₂e
    ↓            ↓               ↓            ↓
Physical     Third-party     kg CO₂e/kg   Total emissions
amount       verified                     (most accurate)

Key characteristics:

Uses Environmental Product Declarations (EPDs) or Product Carbon Footprints (PCFs)
Highest accuracy (±5-15%)
Enables supplier engagement and comparison
Reflects actual supplier practices (e.g., recycled content)

Emission Factor Sources - Supplier-Specific

Supplier-specific emission factors come from:

Environmental Product Declarations (EPDs) - ISO 14025 compliant
Product Carbon Footprints (PCFs) - ISO 14067 compliant
Supplier self-declarations - Verified or unverified

In Dcycle, these are stored as Custom Emission Factors and linked to purchases.

Calculation Details - Supplier-Specific

Supplier-specific emissions are calculated as:CO₂e = Quantity × Custom Emission Factor (kg CO₂e/unit)Where:

Quantity: Physical amount from purchase
Custom Emission Factor: Supplier-provided factor (from EPD/PCF)

Example (Recycled Aluminum from certified supplier):

1,000 kg × 2.15 kg CO₂e/kg = 2,150 kg CO₂e
(vs 8,500 kg CO₂e with generic factor - 75% reduction!)

This method enables:

Accurate supplier comparisons
Recognition of low-carbon suppliers
Data for supplier engagement programs

Automatic Method SelectionDcycle automatically selects the calculation method based on the data provided:

custom_emission_factor_id provided → Supplier-specific method
quantity + physical unit_id provided → Activity-based method
quantity in currency unit (€) → Spend-based method

Data Flow

Set Up Suppliers (Optional)

Create supplier records to organize purchases and enable supplier-level reporting

Choose Calculation Method

Determine which method to use based on available data (spend-based, activity-based, or supplier-specific)

Create Purchases

Record purchases via API or bulk CSV upload with appropriate fields for chosen method

Automatic Calculation

Dcycle automatically calculates CO₂e using Exiobase (spend-based), activity factors, or custom EFs

Query and Analyze

View emissions by supplier, category, or period for hotspot identification

Step 4.1: Set Up Purchase Suppliers

📋 Data Map: Purchase Supplier

Field	Type	Required	Description	Example
`business_name`	string	✅	Supplier company name	`"Green Materials Co"`
`tax_id`	string	✅	Tax identification number	`"B12345678"`
`country`	string	✅	Supplier country (ISO code)	`"ES"`, `"FR"`, `"DE"`
`sector`	string	❌	Business sector	`"Manufacturing"`
`contact_email`	string	❌	Contact email	`"contact@supplier.com"`
`supplier_code`	string	❌	Sectorial code (SIC (US 1987)/CNAE (2009))	`"3331"`

Where to get this data:

Business name/Tax ID: From supplier invoices or contracts
Country: Supplier headquarters or production location
Sector: Industry classification (helps with reporting)

Organize purchases by supplier to enable supplier-level emissions reporting and engagement:

import requests
import os

headers = {
    "Authorization": f"Bearer {os.getenv('DCYCLE_API_KEY')}",
    "Content-Type": "application/json",
    "x-organization-id": os.getenv("DCYCLE_ORG_ID"),
    "x-user-id": os.getenv("DCYCLE_USER_ID"),
}

# Create a purchase supplier
supplier_data = {
    "business_name": "Green Materials Co",
    "tax_id": "B12345678",
    "country": "ES",
    "sector": "Manufacturing",
    "contact_email": "procurement@greenmaterials.com",
}

response = requests.post(
    "https://api.dcycle.io/v1/purchase_suppliers",
    headers=headers,
    json=supplier_data,
)

supplier = response.json()
print(f"✅ Supplier created: {supplier['id']}")
print(f"   Name: {supplier['business_name']}")
print(f"   Country: {supplier['country']}")

const axios = require('axios');

const headers = {
  Authorization: `Bearer ${process.env.DCYCLE_API_KEY}`,
  'Content-Type': 'application/json',
  'x-organization-id': process.env.DCYCLE_ORG_ID,
  'x-user-id': process.env.DCYCLE_USER_ID,
};

// Create a purchase supplier
const supplierData = {
  business_name: 'Green Materials Co',
  tax_id: 'B12345678',
  country: 'ES',
  sector: 'Manufacturing',
  contact_email: 'procurement@greenmaterials.com',
};

const response = await axios.post(
  'https://api.dcycle.io/v1/purchase_suppliers',
  supplierData,
  { headers }
);

const supplier = response.data;
console.log(`✅ Supplier created: ${supplier.id}`);
console.log(`   Name: ${supplier.business_name}`);
console.log(`   Country: ${supplier.country}`);

Supplier Organization Best Practices

Group purchases by supplier for better hotspot analysis
Include supplier country for accurate regional emission factors
Use consistent supplier codes across your ERP and Dcycle

Step 4.2: Create a Spend-Based Purchase

📋 Data Map: Spend-Based Purchase

Field	Type	Required	Description	Example
`description`	string	❌	Purchase description	`"IT consulting Q1"`
`sector`	string	✅	Economic sector	`"Computer programming, consultancy"`
`product_name`	string	✅	Product/service category	`"Computer programming services"`
`quantity`	number	✅	Monetary value spent	`15000`
`unit_id`	UUID	✅	Currency unit (€)	`"eur-unit-uuid"`
`country`	string	✅	Supplier country	`"ES"`
`purchase_date`	date	✅	Date of purchase	`"2024-03-15"`
`supplier_id`	UUID	❌	Linked supplier	`"supplier-uuid"`
`purchase_type`	string	✅	Must be `"spend_based"`	`"spend_based"`

Where to get this data:

Quantity: From invoices, payment records, or ERP exports
Sector/Product: Map from your expense categories (see Exiobase mapping)
Country: Supplier’s country of origin

Use the spend-based method when you only have monetary values:

import requests
import os

headers = {
    "Authorization": f"Bearer {os.getenv('DCYCLE_API_KEY')}",
    "Content-Type": "application/json",
    "x-organization-id": os.getenv("DCYCLE_ORG_ID"),
    "x-user-id": os.getenv("DCYCLE_USER_ID"),
}

# Get the EUR unit for spend-based purchases
units = requests.get(
    "https://api.dcycle.io/v1/units",
    headers=headers,
    params={"page": 1, "size": 100}
).json()

eur_unit = next(u for u in units['items'] if u['abbreviation'] == '€')

# Create spend-based purchase (IT consulting services)
purchase_data = {
    "description": "IT consulting services Q1 2024",
    "sector": "Computer programming, consultancy and related activities",
    "product_name": "Computer programming, consultancy and related services",
    "quantity": 15000,  # €15,000 spent
    "unit_id": eur_unit['id'],  # EUR unit
    "country": "ES",  # Supplier country
    "purchase_date": "2024-03-15",
    "supplier_id": "your-supplier-uuid",  # Optional
    "purchase_type": "spend_based",
}

response = requests.post(
    "https://api.dcycle.io/v1/purchases",
    headers=headers,
    json=purchase_data,
)

purchase = response.json()
print(f"✅ Spend-based purchase created: {purchase['id']}")
print(f"   Amount: €{purchase['quantity']:,.2f}")
print(f"   CO₂e: {purchase.get('co2e', 'Calculating...')} kg")
print(f"   Method: Spend-based (Exiobase 3.8.2)")

const axios = require('axios');

const headers = {
  Authorization: `Bearer ${process.env.DCYCLE_API_KEY}`,
  'Content-Type': 'application/json',
  'x-organization-id': process.env.DCYCLE_ORG_ID,
  'x-user-id': process.env.DCYCLE_USER_ID,
};

// Get the EUR unit for spend-based purchases
const unitsResponse = await axios.get(
  'https://api.dcycle.io/v1/units',
  { headers, params: { page: 1, size: 100 } }
);
const units = unitsResponse.data;
const eurUnit = units.items.find(u => u.abbreviation === '€');

// Create spend-based purchase (IT consulting services)
const purchaseData = {
  description: 'IT consulting services Q1 2024',
  sector: 'Computer programming, consultancy and related activities',
  product_name: 'Computer programming, consultancy and related services',
  quantity: 15000, // €15,000 spent
  unit_id: eurUnit.id, // EUR unit
  country: 'ES', // Supplier country
  purchase_date: '2024-03-15',
  supplier_id: 'your-supplier-uuid', // Optional
  purchase_type: 'spend_based',
};

const response = await axios.post(
  'https://api.dcycle.io/v1/purchases',
  purchaseData,
  { headers }
);

const purchase = response.data;
console.log(`✅ Spend-based purchase created: ${purchase.id}`);
console.log(`   Amount: €${purchase.quantity.toLocaleString()}`);
console.log(`   CO₂e: ${purchase.co2e || 'Calculating...'} kg`);
console.log(`   Method: Spend-based (Exiobase 3.8.2)`);

Spend-Based Accuracy LimitationsSpend-based factors have high uncertainty (±50-100%) because:

Price ≠ emissions (expensive ≠ high emissions)
Doesn’t account for specific products or supplier practices
Currency fluctuations affect results

Use spend-based as a starting point, then improve data quality for high-impact categories.

Step 4.3: Create an Activity-Based Purchase

📋 Data Map: Activity-Based Purchase

Field	Type	Required	Description	Example
`description`	string	❌	Purchase description	`"Aluminum sheets for production"`
`sector`	string	✅	Product sector	`"Manufacture of basic metals"`
`product_name`	string	✅	Specific product	`"Aluminium and aluminium products"`
`quantity`	number	✅	Physical quantity	`1000`
`unit_id`	UUID	✅	Physical unit (kg, m³, etc.)	`"kg-unit-uuid"`
`country`	string	✅	Country of origin	`"ES"`
`purchase_date`	date	✅	Date of purchase	`"2024-03-15"`
`supplier_id`	UUID	❌	Linked supplier	`"supplier-uuid"`
`purchase_type`	string	✅	Must be `"activity_based"`	`"activity_based"`
`recycled`	number	❌	Recycled content (0-1)	`0.3` (30% recycled)

Where to get this data:

Quantity: From delivery notes, bills of materials, or inventory systems
Unit: Match the physical unit of the product (kg for materials, m³ for liquids)
Recycled: Ask supplier for recycled content percentage

Use the activity-based method when you have physical quantities:

import requests
import os

headers = {
    "Authorization": f"Bearer {os.getenv('DCYCLE_API_KEY')}",
    "Content-Type": "application/json",
    "x-organization-id": os.getenv("DCYCLE_ORG_ID"),
    "x-user-id": os.getenv("DCYCLE_USER_ID"),
}

# Get the kg unit for activity-based purchases
units = requests.get(
    "https://api.dcycle.io/v1/units",
    headers=headers,
    params={"page": 1, "size": 100}
).json()

kg_unit = next(u for u in units['items'] if u['abbreviation'] == 'kg')

# Create activity-based purchase (aluminum sheets)
purchase_data = {
    "description": "Aluminum sheets for Q1 production",
    "sector": "Manufacture of basic metals",
    "product_name": "Aluminium and aluminium products",
    "quantity": 1000,  # 1,000 kg
    "unit_id": kg_unit['id'],  # kg unit
    "country": "ES",  # Country of origin
    "purchase_date": "2024-03-15",
    "supplier_id": "your-supplier-uuid",  # Recommended
    "purchase_type": "activity_based",
    "recycled": 0.0,  # 0% recycled content (optional)
}

response = requests.post(
    "https://api.dcycle.io/v1/purchases",
    headers=headers,
    json=purchase_data,
)

purchase = response.json()
print(f"✅ Activity-based purchase created: {purchase['id']}")
print(f"   Quantity: {purchase['quantity']:,.0f} kg")
print(f"   CO₂e: {purchase.get('co2e', 'Calculating...')} kg")
print(f"   Method: Activity-based")

const axios = require('axios');

const headers = {
  Authorization: `Bearer ${process.env.DCYCLE_API_KEY}`,
  'Content-Type': 'application/json',
  'x-organization-id': process.env.DCYCLE_ORG_ID,
  'x-user-id': process.env.DCYCLE_USER_ID,
};

// Get the kg unit for activity-based purchases
const unitsResponse = await axios.get(
  'https://api.dcycle.io/v1/units',
  { headers, params: { page: 1, size: 100 } }
);
const units = unitsResponse.data;
const kgUnit = units.items.find(u => u.abbreviation === 'kg');

// Create activity-based purchase (aluminum sheets)
const purchaseData = {
  description: 'Aluminum sheets for Q1 production',
  sector: 'Manufacture of basic metals',
  product_name: 'Aluminium and aluminium products',
  quantity: 1000, // 1,000 kg
  unit_id: kgUnit.id, // kg unit
  country: 'ES', // Country of origin
  purchase_date: '2024-03-15',
  supplier_id: 'your-supplier-uuid', // Recommended
  purchase_type: 'activity_based',
  recycled: 0.0, // 0% recycled content (optional)
};

const response = await axios.post(
  'https://api.dcycle.io/v1/purchases',
  purchaseData,
  { headers }
);

const purchase = response.data;
console.log(`✅ Activity-based purchase created: ${purchase.id}`);
console.log(`   Quantity: ${purchase.quantity.toLocaleString()} kg`);
console.log(`   CO₂e: ${purchase.co2e || 'Calculating...'} kg`);
console.log(`   Method: Activity-based`);

Track Recycled ContentIf your supplier provides recycled materials, use the recycled field (0-1) to indicate the percentage. This:

Improves calculation accuracy
Enables tracking of circular economy metrics
Supports supplier engagement on recycled content

Step 4.4: Create a Supplier-Specific Purchase

📋 Data Map: Supplier-Specific Purchase

Field	Type	Required	Description	Example
`description`	string	❌	Purchase description	`"Recycled aluminum (EPD verified)"`
`quantity`	number	✅	Physical quantity	`1000`
`unit_id`	UUID	✅	Physical unit	`"kg-unit-uuid"`
`purchase_date`	date	✅	Date of purchase	`"2024-03-15"`
`supplier_id`	UUID	✅	Linked supplier	`"supplier-uuid"`
`custom_emission_factor_id`	UUID	✅	Custom EF from supplier EPD	`"custom-ef-uuid"`
`country`	string	❌	Supplier country	`"ES"`

Where to get this data:

Custom Emission Factor: Create from supplier EPD/PCF (see below)
Quantity: From delivery notes or purchase orders
Supplier ID: From your supplier setup

For highest accuracy, use supplier-provided emission data (EPDs, PCFs):

import requests
import os

headers = {
    "Authorization": f"Bearer {os.getenv('DCYCLE_API_KEY')}",
    "Content-Type": "application/json",
    "x-organization-id": os.getenv("DCYCLE_ORG_ID"),
    "x-user-id": os.getenv("DCYCLE_USER_ID"),
}

# Step 1: Create a custom emission factor group for the supplier
group_data = {
    "name": "Green Materials Co - 2024 Product Line",
    "description": "EPD-verified emission factors from Green Materials Co",
    "category": "purchases",
    "ghg_type": 1,  # 1 = Fossil
}

group = requests.post(
    "https://api.dcycle.io/v1/custom_emission_groups",
    headers=headers,
    json=group_data,
).json()

print(f"✅ Custom EF group created: {group['id']}")

# Step 2: Add emission factor values from the supplier's EPD
kg_unit_id = "61743a63-ff70-459c-9567-5eee8f7dfd5c"  # kg unit UUID

factor_data = {
    "ef_name": "Recycled Aluminum Sheet - Green Materials Co (EPD S-P-12345)",
    "unit_id": kg_unit_id,
    "factor_uploaded_by": "procurement@yourcompany.com",
    "tag": "advanced",
    "uncertainty_grade": 12,  # Low uncertainty (EPD-verified)
    "factor_start_date": "2024-01-01",
    "factor_end_date": "2024-12-31",
    "additional_docs": "EPD No. S-P-12345, Bureau Veritas verified",
    "emission_factor_values": [
        {"gas_type": "CO2", "value": 2.15},  # kg CO2 per kg
        {"gas_type": "CH4", "value": 0.008},  # kg CH4 per kg
        {"gas_type": "N2O", "value": 0.002},  # kg N2O per kg
    ],
}

factor = requests.post(
    f"https://api.dcycle.io/v1/custom_emission_factors/{group['id']}",
    headers=headers,
    json=factor_data,
).json()

print(f"✅ Custom emission factor created: {factor['id']}")

# Step 3: Create purchase using the custom emission factor
purchase_data = {
    "description": "Recycled aluminum sheets from Green Materials Co",
    "quantity": 1000,  # 1,000 kg
    "unit_id": kg_unit_id,
    "purchase_date": "2024-03-15",
    "supplier_id": "your-supplier-uuid",
    "custom_emission_factor_id": factor['id'],  # Use supplier's verified factor
}

response = requests.post(
    "https://api.dcycle.io/v1/purchases",
    headers=headers,
    json=purchase_data,
)

purchase = response.json()
print(f"✅ Supplier-specific purchase created: {purchase['id']}")
print(f"   Quantity: {purchase['quantity']:,.0f} kg")
print(f"   CO₂e: {purchase.get('co2e', 'Calculating...')} kg")
print(f"   Method: Supplier-specific (EPD S-P-12345)")

# Compare with generic factor
generic_co2e = 1000 * 8.5  # Generic aluminum EF
supplier_co2e = 1000 * 2.15  # Supplier's recycled aluminum EF
savings = generic_co2e - supplier_co2e
print(f"\n📊 Emission savings vs generic: {savings:,.0f} kg CO₂e ({savings/generic_co2e*100:.0f}%)")

Why Supplier-Specific MattersUsing supplier-specific data (EPDs, PCFs) provides:

Higher accuracy (±5-15% vs ±50-100% for spend-based)
Recognition for low-carbon suppliers (recycled materials, renewable energy)
Data for supplier engagement programs
Credibility for external reporting and audits

Start with high-emission categories: typically metals, chemicals, electronics.

Bulk Upload Purchases

For large datasets from ERP systems:

CSV Format for Purchases

description,sector,product_name,quantity,unit_id,country,purchase_date,supplier_id,purchase_type,recycled
"Aluminum sheets Q1",Manufacture of basic metals,Aluminium and aluminium products,1000,kg-unit-uuid,ES,2024-03-01,supplier-uuid-1,activity_based,0.0
"Steel beams Q1",Manufacture of basic metals,Basic iron and steel,5000,kg-unit-uuid,DE,2024-03-05,supplier-uuid-2,activity_based,0.3
"IT consulting",Computer programming consultancy,Computer programming services,15000,eur-unit-uuid,ES,2024-03-10,supplier-uuid-3,spend_based,

Upload Process

# Get presigned URL for bulk upload
upload_response = requests.post(
    "https://api.dcycle.io/v1/purchases/bulk/csv",
    headers=headers,
    json={"file_name": "q1_2024_purchases.csv"},
).json()

# Upload CSV to presigned URL
with open('q1_2024_purchases.csv', 'rb') as f:
    requests.put(upload_response['upload_url'], data=f)

print(f"✅ CSV uploaded, processing will begin automatically")
print(f"   Check processing status in the Dcycle App")

Query Purchases and Emissions

Get Purchases by Period

# Query purchases for a specific period
response = requests.get(
    "https://api.dcycle.io/v1/purchases",
    headers=headers,
    params={
        "page": 1,
        "size": 50,
        "start_date": "2024-01-01",
        "end_date": "2024-03-31",
    },
).json()

print(f"📊 Q1 2024 Purchases:")
total_co2e = 0
for purchase in response["items"]:
    print(f"   {purchase['description']}")
    print(f"   Quantity: {purchase['quantity']} {purchase['unit']}")
    print(f"   CO₂e: {purchase['co2e']:.2f} kg")
    print(f"   Method: {purchase['purchase_type']}")
    print()
    total_co2e += purchase['co2e']

print(f"   Total CO₂e: {total_co2e:,.2f} kg")

Get Supplier Emissions Report

# Get emissions by supplier
supplier_id = "your-supplier-uuid"

response = requests.get(
    f"https://api.dcycle.io/v1/purchase_suppliers/{supplier_id}",
    headers=headers,
    params={
        "start_date": "2024-01-01",
        "end_date": "2024-12-31",
    },
).json()

print(f"📊 Supplier Report: {response['business_name']}")
print(f"   Total purchases: {response['total_purchases']}")
print(f"   Total CO₂e: {response['total_co2e']:,.2f} kg")

Best Practice: Prioritize Data Quality ImprovementFor complete Scope 3 Category 1 accounting:

Start with spend-based for broad coverage
Identify hotspots (top 10-20 categories by emissions)
Improve data quality for hotspots (move to activity-based)
Engage key suppliers for EPDs/PCFs (top 20% by emissions)

Goal: Move from 100% spend-based to 50%+ activity/supplier-specific.

Exiobase Sector and Product Mapping

Dcycle uses Exiobase 3.8.2 for spend-based emission factors. Here are the most common sectors:

Sector	Example Products	Typical EF Range (kg CO₂e/€)
Manufacture of basic metals	Steel, aluminum, copper	0.8 - 2.5
Manufacture of chemicals	Industrial chemicals, plastics	0.5 - 1.5
Manufacture of electrical equipment	Electronics, components	0.3 - 0.8
Computer programming, consultancy	IT services, software	0.1 - 0.3
Manufacture of textiles	Fabrics, clothing	0.4 - 1.2
Manufacture of paper	Packaging, office supplies	0.3 - 0.8
Professional services	Consulting, legal	0.1 - 0.2

Full Exiobase Sector List

Contact Dcycle support for the complete Exiobase sector and product mapping for your industry.The mapping includes:

200+ product categories
44 countries with regional factors
Annual updates based on economic data

Custom Sector Mapping

If your expense categories don’t match Exiobase sectors directly, you can:

Use the closest matching sector
Create custom mappings via the API
Contact Dcycle support for assistance

Consistent mapping is key for year-over-year comparisons.

Troubleshooting

Issue: High Uncertainty in Spend-Based Calculations

# Check calculation method and improve data quality
purchase = requests.get(
    f"https://api.dcycle.io/v1/purchases/{purchase_id}",
    headers=headers,
).json()

if purchase['purchase_type'] == 'spend_based':
    print("⚠️  Using spend-based method (high uncertainty)")
    print("💡 Recommendations:")
    print("   1. Collect physical quantities from supplier")
    print("   2. Request product specifications")
    print("   3. Ask supplier for EPD/PCF data")

Issue: Can’t Find Appropriate Sector/Product

# Use the most specific category available
# If unsure, use broader category and refine later

# Too broad: "Manufacturing"
# Better: "Manufacture of basic metals"
# Best: "Aluminium and aluminium products"

# You can update the sector later:
requests.patch(
    f"https://api.dcycle.io/v1/purchases/{purchase_id}",
    headers=headers,
    json={
        "sector": "Manufacture of basic metals",
        "product_name": "Aluminium and aluminium products",
    },
)

Issue: Supplier Data Not Available

# Track without supplier initially, link later
purchase_data = {
    "description": "Office supplies Q1",
    "sector": "Manufacture of paper and paper products",
    "product_name": "Paper and paper products",
    "quantity": 500,  # €500
    "unit_id": eur_unit_id,
    "purchase_date": "2024-03-15",
    "purchase_type": "spend_based",
    # supplier_id: omitted - can add later
}

# Later, link to supplier:
requests.patch(
    f"https://api.dcycle.io/v1/purchases/{purchase_id}",
    headers=headers,
    json={"supplier_id": "supplier-uuid"},
)

Next Steps

Now that you understand Category 1, continue with:

Supply Chain Tutorial

Complete supply chain management workflow

Custom Emission Factors

Create and manage supplier EPDs/PCFs

Category 4: Upstream Transport

Track transportation of purchased goods

Logistics Tutorial

Complete logistics and transport tracking

Calculate Emissions

ISO 14064

GHG Protocol

GLEC v3.0 Framework

Use Case Tutorials

Life Cycle Assessment (LCA)

Own Workforce (Social Data)

ISO 14001 Management Systems

Advanced

Automation & AI

S3. Category 1: Purchased Goods and Services

Understanding Scope 3 Category 1

Prerequisites

Data Map: Purchased Goods & Services Requirements Overview

Calculation Methods

Data Quality Hierarchy

Data Flow

Step 4.1: Set Up Purchase Suppliers

Step 4.2: Create a Spend-Based Purchase

Step 4.3: Create an Activity-Based Purchase

Step 4.4: Create a Supplier-Specific Purchase

Bulk Upload Purchases

CSV Format for Purchases

Upload Process

Query Purchases and Emissions

Get Purchases by Period

Get Supplier Emissions Report

Exiobase Sector and Product Mapping

Troubleshooting

Issue: High Uncertainty in Spend-Based Calculations

Issue: Can’t Find Appropriate Sector/Product

Issue: Supplier Data Not Available

Next Steps

Supply Chain Tutorial

Custom Emission Factors

Category 4: Upstream Transport

Logistics Tutorial

​Understanding Scope 3 Category 1

​Prerequisites

​Data Map: Purchased Goods & Services Requirements Overview

​Calculation Methods

​Data Quality Hierarchy

​Data Flow

​Step 4.1: Set Up Purchase Suppliers

​Step 4.2: Create a Spend-Based Purchase

​Step 4.3: Create an Activity-Based Purchase

​Step 4.4: Create a Supplier-Specific Purchase

​Bulk Upload Purchases

​CSV Format for Purchases

​Upload Process

​Query Purchases and Emissions

​Get Purchases by Period

​Get Supplier Emissions Report

​Exiobase Sector and Product Mapping

​Troubleshooting

​Issue: High Uncertainty in Spend-Based Calculations

​Issue: Can’t Find Appropriate Sector/Product

​Issue: Supplier Data Not Available

​Next Steps

Supply Chain Tutorial

Custom Emission Factors

Category 4: Upstream Transport

Logistics Tutorial

Understanding Scope 3 Category 1

Prerequisites

Data Map: Purchased Goods & Services Requirements Overview

Calculation Methods

Data Quality Hierarchy

Data Flow

Step 4.1: Set Up Purchase Suppliers

Step 4.2: Create a Spend-Based Purchase

Step 4.3: Create an Activity-Based Purchase

Step 4.4: Create a Supplier-Specific Purchase

Bulk Upload Purchases

CSV Format for Purchases

Upload Process

Query Purchases and Emissions

Get Purchases by Period

Get Supplier Emissions Report

Exiobase Sector and Product Mapping

Troubleshooting

Issue: High Uncertainty in Spend-Based Calculations

Issue: Can’t Find Appropriate Sector/Product

Issue: Supplier Data Not Available

Next Steps