--- slug: "co2-carbon-footprint" display_name: "Co2 Carbon Footprint" description: "Calculate CO2 emissions and carbon footprint from BIM model data. Analyze embodied carbon by material, element, and building system." --- # 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 ```python 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 MaterialCategory.TIMBER if any(w in name_lower for w in ['aluminum', 'aluminium']): return MaterialCategory.ALUMINUM if any(w in name_lower for w in ['glass', 'glazing']): return MaterialCategory.GLASS if any(w in name_lower for w in ['brick', 'masonry', 'block']): return MaterialCategory.BRICK if any(w in name_lower for w in ['insulation', 'wool', 'foam', 'eps', 'xps']): return MaterialCategory.INSULATION if any(w in name_lower for w in ['gypsum', 'drywall', 'plaster']): return MaterialCategory.GYPSUM return MaterialCategory.OTHER class CO2FootprintCalculator: """Calculate carbon footprint from BIM data.""" def __init__(self, coefficient_db: CarbonCoefficientDatabase = None): self.db = coefficient_db or CarbonCoefficientDatabase() self.results: List[CarbonResult] = [] self.warnings: List[str] = [] def calculate_element(self, element: Dict[str, Any], stage: LifeCycleStage = LifeCycleStage.A1_A3) -> Optional[CarbonResult]: """Calculate carbon for single element.""" material = element.get('material', '') if not material: self.warnings.append(f"Element {element.get('element_id')} has no material") return None coefficient = self.db.find_coefficient(material, stage) if not coefficient: self.warnings.append(f"No coefficient found for material: {material}") return None # Get quantity in correct unit quantity = self._get_quantity(element, coefficient.unit) if quantity is None or quantity <= 0: return None total_kgco2 = quantity * coefficient.kgco2_per_unit result = CarbonResult( element_id=str(element.get('element_id', '')), element_name=str(element.get('name', '')), material=material, category=coefficient.category, quantity=quantity, unit=coefficient.unit, kgco2_per_unit=coefficient.kgco2_per_unit, total_kgco2=total_kgco2, stage=stage, level=str(element.get('level', '')) ) self.results.append(result) return result def _get_quantity(self, element: Dict[str, Any], unit: str) -> Optional[float]: """Get quantity in required unit.""" unit_lower = unit.lower() if unit_lower == 'm3': return float(element.get('volume', 0) or 0) elif unit_lower == 'm2': return float(element.get('area', 0) or 0) elif unit_lower in ['kg', 'kilogram']: # Try weight, then estimate from volume weight = element.get('weight', 0) if weight: return float(weight) # Estimate from volume with density volume = element.get('volume', 0) if volume: density = self._estimate_density(element.get('material', '')) return float(volume) * density elif unit_lower in ['m', 'meter']: return float(element.get('length', 0) or 0) return None def _estimate_density(self, material: str) -> float: """Estimate material density in kg/m3.""" material_lower = material.lower() densities = { 'concrete': 2400, 'steel': 7850, 'timber': 500, 'aluminum': 2700, 'glass': 2500, 'brick': 1800, 'gypsum': 800 } for key, density in densities.items(): if key in material_lower: return density return 1500 # Default density def calculate_from_dataframe(self, df: pd.DataFrame, stage: LifeCycleStage = LifeCycleStage.A1_A3) -> List[CarbonResult]: """Calculate carbon for all elements in DataFrame.""" self.results = [] self.warnings = [] for _, row in df.iterrows(): self.calculate_element(row.to_dict(), stage) return self.results def get_summary(self, gfa: float = 0) -> CarbonSummary: """Generate carbon footprint summary.""" by_material = {} by_category = {} by_stage = {} by_level = {} for result in self.results: # By material by_material[result.material] = by_material.get(result.material, 0) + result.total_kgco2 # By category cat = result.category.value by_category[cat] = by_category.get(cat, 0) + result.total_kgco2 # By stage stg = result.stage.value by_stage[stg] = by_stage.get(stg, 0) + result.total_kgco2 # By level if result.level: by_level[result.level] = by_level.get(result.level, 0) + result.total_kgco2 total_kgco2 = sum(r.total_kgco2 for r in self.results) return CarbonSummary( total_kgco2=round(total_kgco2, 2), total_tonco2=round(total_kgco2 / 1000, 2), by_material=by_material, by_category=by_category, by_stage=by_stage, by_level=by_level, element_count=len(self.results), gfa=gfa, kgco2_per_m2=round(total_kgco2 / gfa, 2) if gfa > 0 else 0 ) def export_results(self, output_path: str): """Export results to Excel.""" with pd.ExcelWriter(output_path, engine='openpyxl') as writer: # Detailed results results_df = pd.DataFrame([{ 'Element ID': r.element_id, 'Element Name': r.element_name, 'Material': r.material, 'Category': r.category.value, 'Quantity': r.quantity, 'Unit': r.unit, 'kg CO2e/unit': r.kgco2_per_unit, 'Total kg CO2e': round(r.total_kgco2, 2), 'Level': r.level } for r in self.results]) results_df.to_excel(writer, sheet_name='Details', index=False) # Summary summary = self.get_summary() summary_df = pd.DataFrame([ {'Metric': 'Total kg CO2e', 'Value': summary.total_kgco2}, {'Metric': 'Total ton CO2e', 'Value': summary.total_tonco2}, {'Metric': 'Elements Analyzed', 'Value': summary.element_count} ]) summary_df.to_excel(writer, sheet_name='Summary', index=False) return output_path ``` ## Quick Start ```python # Initialize calculator calculator = CO2FootprintCalculator() # Load BIM quantities elements = pd.read_excel("bim_quantities.xlsx") # Calculate carbon results = calculator.calculate_from_dataframe(elements) # Get summary summary = calculator.get_summary(gfa=5000) # 5000 m2 GFA print(f"Total: {summary.total_tonco2} ton CO2e") print(f"Per m2: {summary.kgco2_per_m2} kg CO2e/m2") ``` ## Common Use Cases ### 1. Material Comparison ```python # Compare concrete vs timber concrete_elements = elements[elements['material'].str.contains('Concrete')] timber_elements = elements[elements['material'].str.contains('Timber')] ``` ### 2. Target Compliance ```python TARGET_KGCO2_M2 = 500 # LEED/BREEAM target if summary.kgco2_per_m2 > TARGET_KGCO2_M2: print(f"Warning: Exceeds target by {summary.kgco2_per_m2 - TARGET_KGCO2_M2} kg/m2") ``` ### 3. Export Report ```python calculator.export_results("carbon_report.xlsx") ``` ## Resources - **DDC Book**: Chapter 3.3 - CO2 Estimation - **Reference**: EN 15978, EPD databases