lifecycle-carbon-calculator

What this skill does

# Lifecycle Carbon Calculator for Construction

## Overview

Calculate embodied carbon (EC) and lifecycle carbon emissions for construction materials, assemblies, and projects. Support sustainable design decisions and carbon reduction targets.

## Business Case

Carbon calculation supports:
- **Regulatory Compliance**: Meet carbon reporting requirements
- **Green Certifications**: LEED, BREEAM, Living Building Challenge
- **Design Optimization**: Choose lower-carbon alternatives
- **Sustainability Goals**: Track progress toward net-zero

## Technical Implementation

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

class LifecycleStage(Enum):
    A1_A3 = "Product Stage (A1-A3)"  # Raw materials, transport, manufacturing
    A4 = "Transport to Site (A4)"
    A5 = "Construction (A5)"
    B1_B7 = "Use Stage (B1-B7)"  # Maintenance, repair, replacement
    C1_C4 = "End of Life (C1-C4)"  # Demolition, transport, disposal
    D = "Beyond Lifecycle (D)"  # Reuse, recycling potential

@dataclass
class MaterialCarbon:
    material_id: str
    name: str
    category: str
    unit: str
    carbon_a1_a3: float  # kgCO2e per unit
    carbon_a4: float
    carbon_a5: float
    carbon_b: float
    carbon_c: float
    carbon_d: float  # Usually negative (credit)
    density: float  # kg/m³ if applicable
    source: str
    epd_url: str = ""

@dataclass
class AssemblyCarbon:
    assembly_id: str
    name: str
    materials: List[Dict[str, Any]]
    total_carbon: float
    carbon_by_stage: Dict[str, float]

@dataclass
class ProjectCarbon:
    project_id: str
    name: str
    gross_area: float
    assemblies: List[AssemblyCarbon]
    total_embodied_carbon: float
    carbon_per_area: float
    carbon_by_stage: Dict[str, float]
    carbon_by_category: Dict[str, float]
    benchmark_comparison: Dict[str, Any]

class LifecycleCarbonCalculator:
    """Calculate lifecycle carbon for construction."""

    # Sample material carbon data (kgCO2e per unit)
    DEFAULT_MATERIALS = {
        'concrete_30mpa': MaterialCarbon(
            material_id='C30', name='Concrete 30MPa', category='Concrete',
            unit='m³', carbon_a1_a3=300, carbon_a4=5, carbon_a5=2,
            carbon_b=0, carbon_c=10, carbon_d=-20, density=2400,
            source='EPD Database'
        ),
        'concrete_40mpa': MaterialCarbon(
            material_id='C40', name='Concrete 40MPa', category='Concrete',
            unit='m³', carbon_a1_a3=350, carbon_a4=5, carbon_a5=2,
            carbon_b=0, carbon_c=10, carbon_d=-20, density=2400,
            source='EPD Database'
        ),
        'steel_rebar': MaterialCarbon(
            material_id='REBAR', name='Steel Reinforcing Bar', category='Steel',
            unit='kg', carbon_a1_a3=1.99, carbon_a4=0.05, carbon_a5=0.02,
            carbon_b=0, carbon_c=0.05, carbon_d=-0.5, density=7850,
            source='WorldSteel EPD'
        ),
        'steel_structural': MaterialCarbon(
            material_id='STEEL', name='Structural Steel', category='Steel',
            unit='kg', carbon_a1_a3=1.55, carbon_a4=0.05, carbon_a5=0.03,
            carbon_b=0, carbon_c=0.05, carbon_d=-0.8, density=7850,
            source='AISC EPD'
        ),
        'timber_clt': MaterialCarbon(
            material_id='CLT', name='Cross-Laminated Timber', category='Timber',
            unit='m³', carbon_a1_a3=-500, carbon_a4=10, carbon_a5=5,
            carbon_b=0, carbon_c=50, carbon_d=-100, density=500,
            source='AWC EPD'
        ),
        'gypsum_board': MaterialCarbon(
            material_id='GYP', name='Gypsum Board 12.5mm', category='Finishes',
            unit='m²', carbon_a1_a3=3.2, carbon_a4=0.2, carbon_a5=0.1,
            carbon_b=0, carbon_c=0.3, carbon_d=-0.1, density=10,
            source='EUROGYPSUM EPD'
        ),
        'insulation_mineral': MaterialCarbon(
            material_id='INS_MW', name='Mineral Wool Insulation', category='Insulation',
            unit='m³', carbon_a1_a3=45, carbon_a4=2, carbon_a5=1,
            carbon_b=0, carbon_c=5, carbon_d=-2, density=40,
            source='EURIMA EPD'
        ),
        'glass_double': MaterialCarbon(
            material_id='GLASS', name='Double Glazed Unit', category='Glazing',
            unit='m²', carbon_a1_a3=35, carbon_a4=1, carbon_a5=0.5,
            carbon_b=0, carbon_c=2, carbon_d=-5, density=25,
            source='Glass for Europe EPD'
        ),
        'aluminum': MaterialCarbon(
            material_id='ALU', name='Aluminum Profile', category='Metals',
            unit='kg', carbon_a1_a3=8.0, carbon_a4=0.1, carbon_a5=0.05,
            carbon_b=0, carbon_c=0.1, carbon_d=-4.0, density=2700,
            source='EAA EPD'
        ),
    }

    # Building type benchmarks (kgCO2e/m²)
    BENCHMARKS = {
        'Office': {'typical': 500, 'good': 350, 'best': 200},
        'Residential': {'typical': 400, 'good': 280, 'best': 150},
        'Retail': {'typical': 450, 'good': 320, 'best': 180},
        'Industrial': {'typical': 350, 'good': 250, 'best': 150},
        'Healthcare': {'typical': 700, 'good': 500, 'best': 350},
    }

    def __init__(self):
        self.materials: Dict[str, MaterialCarbon] = dict(self.DEFAULT_MATERIALS)
        self.assemblies: Dict[str, AssemblyCarbon] = {}

    def add_material(self, material: MaterialCarbon):
        """Add or update a material."""
        self.materials[material.material_id] = material

    def calculate_material_carbon(self, material_id: str, quantity: float,
                                   stages: List[LifecycleStage] = None) -> Dict:
        """Calculate carbon for a material quantity."""
        if material_id not in self.materials:
            raise ValueError(f"Unknown material: {material_id}")

        material = self.materials[material_id]

        if stages is None:
            stages = list(LifecycleStage)

        carbon_by_stage = {}
        total = 0

        for stage in stages:
            if stage == LifecycleStage.A1_A3:
                carbon = material.carbon_a1_a3 * quantity
            elif stage == LifecycleStage.A4:
                carbon = material.carbon_a4 * quantity
            elif stage == LifecycleStage.A5:
                carbon = material.carbon_a5 * quantity
            elif stage == LifecycleStage.B1_B7:
                carbon = material.carbon_b * quantity
            elif stage == LifecycleStage.C1_C4:
                carbon = material.carbon_c * quantity
            elif stage == LifecycleStage.D:
                carbon = material.carbon_d * quantity
            else:
                carbon = 0

            carbon_by_stage[stage.value] = carbon
            total += carbon

        return {
            'material_id': material_id,
            'material_name': material.name,
            'quantity': quantity,
            'unit': material.unit,
            'total_carbon': total,
            'carbon_by_stage': carbon_by_stage
        }

    def create_assembly(self, assembly_id: str, name: str,
                        components: List[Dict]) -> AssemblyCarbon:
        """Create an assembly from multiple materials."""
        total_carbon = 0
        carbon_by_stage = {stage.value: 0 for stage in LifecycleStage}
        material_details = []

        for comp in components:
            material_id = comp['material_id']
            quantity = comp['quantity']

            result = self.calculate_material_carbon(material_id, quantity)
            total_carbon += result['total_carbon']

            for stage, carbon in result['carbon_by_stage'].items():
                carbon_by_stage[stage] += carbon

            material_details.append({
                'material': result['material_name'],
                'quantity': quantity,
                'unit': result['unit'],
                'carbon': result['total_carbon']
            })

        assembly = AssemblyCarbon(
            assembly_id=assembly_id,
            name=name,