CO2 Carbon Footprint Calculator

Business Case

Problem Statement

Sustainability requirements demand carbon tracking:

• Need to quantify embodied carbon
• Material selection impact unclear
• Reporting requirements increasing
• No integration with BIM workflow

Solution

Calculate CO2 emissions from BIM quantities using EPD (Environmental Product Declaration) data and carbon coefficients.

Business Value

• Sustainability - Meet green building requirements
• Design optimization - Identify high-carbon elements
• Reporting - Automated carbon reports
• Decision support - Compare material alternatives

Technical Implementation

import pandas as pd
from datetime import datetime
from typing import Dict, Any, List, Optional, Tuple
from dataclasses import dataclass, field
from enum import Enum


class LifeCycleStage(Enum):
    """EN 15978 Life Cycle Stages."""
    A1_A3 = "a1_a3"  # Product stage
    A4 = "a4"        # Transport to site
    A5 = "a5"        # Construction
    B1_B7 = "b1_b7"  # Use stage
    C1_C4 = "c1_c4"  # End of life
    D = "d"          # Beyond system boundary


class MaterialCategory(Enum):
    """Material categories for carbon calculation."""
    CONCRETE = "concrete"
    STEEL = "steel"
    TIMBER = "timber"
    ALUMINUM = "aluminum"
    GLASS = "glass"
    BRICK = "brick"
    INSULATION = "insulation"
    GYPSUM = "gypsum"
    OTHER = "other"


@dataclass
class CarbonCoefficient:
    """Carbon emission coefficient for a material."""
    material: str
    category: MaterialCategory
    kgco2_per_unit: float  # kg CO2e per unit
    unit: str  # kg, m3, m2, etc.
    stage: LifeCycleStage
    source: str  # EPD reference
    uncertainty: float = 0.1  # 10% default uncertainty


@dataclass
class CarbonResult:
    """Carbon calculation result for an element."""
    element_id: str
    element_name: str
    material: str
    category: MaterialCategory
    quantity: float
    unit: str
    kgco2_per_unit: float
    total_kgco2: float
    stage: LifeCycleStage
    level: str = ""
    notes: str = ""


@dataclass
class CarbonSummary:
    """Carbon footprint summary."""
    total_kgco2: float
    total_tonco2: float
    by_material: Dict[str, float]
    by_category: Dict[str, float]
    by_stage: Dict[str, float]
    by_level: Dict[str, float]
    element_count: int
    gfa: float  # Gross Floor Area
    kgco2_per_m2: float


class CarbonCoefficientDatabase:
    """Database of carbon emission coefficients."""

    def __init__(self):
        self.coefficients: List[CarbonCoefficient] = []
        self._load_default_coefficients()

    def _load_default_coefficients(self):
        """Load standard carbon coefficients (EPD-based)."""
        # Concrete products
        self.add_coefficient(CarbonCoefficient(
            material="Concrete C30/37", category=MaterialCategory.CONCRETE,
            kgco2_per_unit=250, unit="m3", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - Concrete"
        ))
        self.add_coefficient(CarbonCoefficient(
            material="Concrete C40/50", category=MaterialCategory.CONCRETE,
            kgco2_per_unit=300, unit="m3", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - High Strength Concrete"
        ))
        self.add_coefficient(CarbonCoefficient(
            material="Reinforcement Steel", category=MaterialCategory.STEEL,
            kgco2_per_unit=1.99, unit="kg", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - Rebar"
        ))

        # Steel products
        self.add_coefficient(CarbonCoefficient(
            material="Structural Steel", category=MaterialCategory.STEEL,
            kgco2_per_unit=2.5, unit="kg", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - Structural Steel"
        ))
        self.add_coefficient(CarbonCoefficient(
            material="Steel Sheet", category=MaterialCategory.STEEL,
            kgco2_per_unit=2.3, unit="kg", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - Sheet Metal"
        ))

        # Timber products
        self.add_coefficient(CarbonCoefficient(
            material="Softwood Timber", category=MaterialCategory.TIMBER,
            kgco2_per_unit=-500, unit="m3", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - CLT (carbon sequestration)"
        ))
        self.add_coefficient(CarbonCoefficient(
            material="Glulam", category=MaterialCategory.TIMBER,
            kgco2_per_unit=-350, unit="m3", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - Glued Laminated Timber"
        ))

        # Aluminum
        self.add_coefficient(CarbonCoefficient(
            material="Aluminum Profile", category=MaterialCategory.ALUMINUM,
            kgco2_per_unit=8.0, unit="kg", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - Aluminum"
        ))

        # Glass
        self.add_coefficient(CarbonCoefficient(
            material="Float Glass", category=MaterialCategory.GLASS,
            kgco2_per_unit=15.0, unit="m2", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - Float Glass"
        ))
        self.add_coefficient(CarbonCoefficient(
            material="Double Glazing Unit", category=MaterialCategory.GLASS,
            kgco2_per_unit=35.0, unit="m2", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - IGU"
        ))

        # Masonry
        self.add_coefficient(CarbonCoefficient(
            material="Clay Brick", category=MaterialCategory.BRICK,
            kgco2_per_unit=0.24, unit="kg", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - Clay Brick"
        ))

        # Insulation
        self.add_coefficient(CarbonCoefficient(
            material="Mineral Wool", category=MaterialCategory.INSULATION,
            kgco2_per_unit=1.2, unit="kg", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - Mineral Wool"
        ))
        self.add_coefficient(CarbonCoefficient(
            material="EPS Insulation", category=MaterialCategory.INSULATION,
            kgco2_per_unit=3.5, unit="kg", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - EPS"
        ))

        # Gypsum
        self.add_coefficient(CarbonCoefficient(
            material="Gypsum Board", category=MaterialCategory.GYPSUM,
            kgco2_per_unit=2.8, unit="m2", stage=LifeCycleStage.A1_A3,
            source="Generic EPD - Plasterboard"
        ))

    def add_coefficient(self, coefficient: CarbonCoefficient):
        """Add carbon coefficient to database."""
        self.coefficients.append(coefficient)

    def find_coefficient(self, material_name: str,
                        stage: LifeCycleStage = LifeCycleStage.A1_A3) -> Optional[CarbonCoefficient]:
        """Find matching coefficient for material."""
        material_lower = material_name.lower()

        # Direct match
        for coef in self.coefficients:
            if coef.material.lower() == material_lower and coef.stage == stage:
                return coef

        # Partial match
        for coef in self.coefficients:
            if material_lower in coef.material.lower() or coef.material.lower() in material_lower:
                if coef.stage == stage:
                    return coef

        # Category match
        category = self._guess_category(material_name)
        for coef in self.coefficients:
            if coef.category == category and coef.stage == stage:
                return coef

        return None

    def _guess_category(self, material_name: str) -> MaterialCategory:
        """Guess material category from name."""
        name_lower = material_name.lower()

        if any(w in name_lower for w in ['concrete', 'cement', 'mortar']):
            return MaterialCategory.CONCRETE
        if any(w in name_lower for w in ['steel', 'iron', 'metal']):
            return MaterialCategory.STEEL
        if any(w in name_lower for w in ['wood', 'timber', 'lumber', 'plywood', 'clt']):
            return Materia