Material Conservation & Carbon Reduction

Cheatsheet Content

Concept of Embodied Energy Definition: Total energy required for extraction, processing, manufacture, and delivery of building materials to the site. Indicator of overall environmental impact (due to $\text{CO}_2$ production). Considers only front-end impact, not operation or disposal. Key Aspects of Embodied Energy Life Cycle Perspective: From raw material extraction to disposal/recycling. Direct Embodied Energy: Energy for manufacturing, transportation, construction (e.g., material production, assembly). Indirect Embodied Energy: Energy for related processes (e.g., mining, infrastructure for production). Energy Sources: Considers fossil fuels, renewables, or a mix. Environmental Impact: Higher embodied energy correlates with increased resource consumption and greenhouse gas emissions. Sustainability & Decision-Making: Essential for informed choices in material selection. Measuring & Reducing: Complex calculation; strategies include recycled materials, optimized manufacturing, reduced transport. Regulations & Standards: Some regions have guidelines for embodied energy. Innovation: Drives development of more environmentally friendly products. Real-World Examples of High Embodied Energy Materials Concrete: Energy-intensive mining, processing, heating, transport of raw materials. Aluminum: Energy-intensive extraction, refining, electrolysis. Steel: Energy-intensive extraction, smelting, refining in blast furnaces. Plastic: Significant energy for extracting, refining, processing petrochemicals. Electronic Devices: Complex supply chains, rare metal mining, energy-intensive manufacturing. Glass: Energy-intensive heating of raw materials to high temperatures. Cement Blocks: High embodied energy due to cement content. Insulation Materials (e.g., fiberglass, foam boards): Energy-intensive manufacturing processes and chemicals. Large Appliances: Complex production, metal components, energy-intensive refrigeration. Why Reduce Embodied Energy? Reducing Carbon Footprint: Lowers greenhouse gas emissions. Conservation of Resources: Preserves finite natural resources. Energy Efficiency: Promotes efficient use of energy resources. Economic Savings: Lowers production costs. Resource Efficiency: Uses materials more effectively, reduces waste. Environmental Impact Reduction: Mitigates habitat destruction, pollution. Regulatory Compliance: Meets sustainability regulations. Consumer Demand: Meets demand for sustainable products. Resilience: Enhances infrastructure and supply chain adaptability. Sustainability: Essential for long-term sustainability goals. Measuring Embodied Energy Quantity of non-renewable energy per unit of material ($\text{MJ/kg}$, $\text{GJ/tonne}$, or $\text{GJ/m}^2$). Complex process involving numerous data sources. Strategies for Reducing Embodied Energy Use Local Materials: Less energy for transportation. Recycle and Reuse Materials: Minimizes energy for new material extraction. Design for Disassembly: Components can be reused/recycled at end-of-life. Optimize Material Selection: Choose materials with lower embodied energy (e.g., bamboo, reclaimed wood). Minimize Waste: Efficient manufacturing processes, minimal offcuts. Energy-Efficient Transportation: Electric/hybrid vehicles, shorter distances. Lightweight Materials: Less energy for transport, can lead to operational energy savings. Considerations for Building Materials Selection Durability of building materials. Ease of material separation. Use of locally sourced materials. Use of recycled materials. Specifying standard sizes of materials. Avoiding waste. Selecting materials manufactured using renewable energy sources. Low Energy Building Materials Earth (Adobe, Rammed Earth, Cob): Excellent thermal mass, regulates indoor temperatures. Sustainable, readily available, low environmental impact. Strong, durable, weather-resistant, fire/pest proof. Can be challenging to find specialized craftsmen. Recycled Steel: Highly recycled material, lower $\text{CO}_2$ emissions. Retains strength and durability. Reduces demand for virgin materials (e.g., 6 scrapped cars vs. 40-50 trees for a house frame). Low-E (Low-Emissive) Windows: Coating reflects heat and UV rays, allows visible light. Maintains consistent indoor temperatures, reduces heating/cooling needs. Can reduce heat flow up to 50%. Cool Roof: Reflective surfaces (e.g., white membranes) reduce heat absorption. Minimizes heat gain, lowers cooling energy consumption. Reflects $\sim 80\%$ of sunlight. Thermostat Radiant Barrier: Reflects $97\%$ of radiant heat, keeps house cool. Reduces cooling energy cost by $\sim 17\%$ in peak summer. Installed in attic to reduce heat gain/loss. Wood or Plastic Composite Lumber: $50/50$ plastic waste and wood fibers. Mould resistant, less toxic than treated wood. Straw Bales: Excellent insulation properties, renewable, low embodied energy. Thermal performance, energy efficiency. Spray Foam Insulation: Low leakage, water resistant, shrink proof. High thermal resistance, minimizes air leakage. Insulating Concrete Forms (ICFs): Concrete poured between insulation materials (e.g., expanded polystyrene). Well-insulated walls, thermal mass, reduces energy consumption. Structural Insulated Panels (SIPs): Insulating foam core between structural facings (e.g., OSB). Excellent insulation, reduced thermal bridging, airtight construction. Save up to $50\%$ more energy than traditional methods. Plant-Based Polyurethane Foam: Made from natural products (hemp, bamboo, kelp, soybean oil). Moisture and heat resistant, works against mould and pests. More environmentally friendly than petroleum-based foams. Sustainable Building Materials Bamboo: Incredibly high self-generation rate, grows without replanting. High strength-to-weight ratio, greater compressive strength than concrete/brick. Requires treatment for insects and rot. Cork: Harvested from bark without harming tree, renewable. Flooring, wall coverings, insulation; naturally insulating, moisture/pest resistant. Excellent noise absorption, shock absorption, thermal insulator, fire resistant. Reclaimed or Recycled Steel: Scrap steel melted and repurposed. $100\%$ recyclable, reduces ecological impact. Long-lasting, no burning/warping, water/pest resistant. Sheep's Wool: Renewable resource, low-impact manufacturing. Excellent thermal performance, soundproofing. Requires treatment for insects/fungi, can be expensive. Rammed Earth: Compacted earth, chalk, lime, stabilizers. Uses local materials, reduces transport emissions, low carbon footprint. Good thermal mass, regulates indoor temperatures. Reclaimed Wood: Saves trees, reduces landfill waste. Good for structural framing, cabinetry, flooring. Integrity needs assessment, susceptible to insects/degradation. HempCrete: Woody inner fibers of hemp plant bound with lime. Lightweight, strong, good thermal/acoustic insulation, fire resistant. $\text{CO}_2$ negative, fast-growing renewable resource. Timbercrete: Mix of sawdust and concrete. Lighter than concrete, reduces transport emissions. Reduces cement use (significant carbon source). Cob: Mix of subsoil, water, fibrous organic material, lime. Natural material, easy to use, allows creative shapes. Natural insulation, very energy efficient. Recycled Plastic: Durable, robust, good sound retention. Reduces waste, carbon-neutral non-toxic manufacturing processes. Ashcrete: Concrete alternative from fly ash (coal combustion waste). Reduces environmental impact of concrete production. Smaller pores, better strength (roughly $2 \times$ Portland cement). Enviroboard: Fire-resistant board from magnesium, sawdust, fiber cloth. Stronger than conventional boards, doesn't warp, water resistant. Green manufacturing, natural drying/curing, no extra carbon emissions. Clay Brick: Made from natural, abundant, locally sourced clay. $100\%$ recyclable, earth-friendly, no toxic chemicals. Energy efficient: keeps house cooler in summer, traps warmth in winter. Need for Alternative Materials Resource Depletion: Reduces reliance on finite resources. Environmental Sustainability: Less harmful production processes. Climate Change Mitigation: Lower carbon footprint options (e.g., bio-based plastics). Energy Efficiency: Lighter materials reduce transport energy, improve building efficiency. Cost Reduction: Can be more cost-effective over lifecycle. Enhanced Performance: Improved strength, durability, corrosion resistance. Hollow Concrete Blocks (CMUs) Made from Portland cement, aggregates, water with hollow voids. Lighter than solid blocks, better insulation. Types: Standard Hollow Concrete Blocks: Common, various sizes. Aerated Concrete Blocks: Lighter, more insulating due to aluminum powder. Styrofoam Concrete Blocks: Styrofoam beads reduce weight, improve insulation. Advantages: Reduced Weight: Easier handling and transport. Thermal Insulation: Hollow voids provide natural insulation. Ease of Handling: Easier placement of reinforcing materials. Versatility: Various sizes/shapes for different applications. Sound Insulation: Air pockets contribute to sound insulation. Applications: Load-Bearing Walls, Partition Walls, Retaining Walls, Facade Construction, Paving. Fly Ash Bricks Alternative building material from fly ash (coal combustion byproduct). Sustainable, eco-friendly alternative to traditional clay bricks. Composition: Fly Ash: Primary raw material, rich in silica, alumina. Cement: Binding agent. Aggregates: Sand or fine aggregates for strength. Water: For mixing and hardening. Advantages: Environmental Sustainability: Utilizes industrial waste. Resource Conservation: Reduces demand for clay, conserves topsoil. Energy Efficiency: Less energy for manufacturing than clay bricks. Cost-Effective: Fly ash often low/no cost. Lightweight: Easier handling and transport. Thermal Insulation: Better insulation properties. Reduced Cracking: Fewer cracks during curing. Uniform Size and Shape: Facilitates construction. Applications: Residential, Commercial, Industrial Construction, Infrastructure Projects, Pavement Construction. Rice Husk Ash (RHA) and Pozzolanas Advantages of Rice Husk Ash: Pozzolanic Properties: Reacts with calcium hydroxide to form strength-contributing compounds in concrete. Reduced Environmental Impact: Utilizes agricultural waste. Increased Concrete Strength: Enhances compressive strength as cement replacement. Improved Workability: Improves workability, reduces water demand in concrete. Applications: Concrete Production (partial cement replacement), Mortar and Plaster, Soil Stabilization. Ferrocement Thin, lightweight, highly durable composite material made of cement mortar reinforced with layers of continuous small-diameter steel mesh. Advantages: Strength and Durability: High strength from cement and metal mesh. Versatility: Moldable into various shapes and sizes. Lightweight: Despite strength, relatively lightweight. Thinness: Can be made very thin, saving material costs. Corrosion Resistance: Metal mesh coated, cement provides protection. Crack Resistance: Good crack resistance due to mesh reinforcement. Cost-Effectiveness: Can be cost-effective for specific applications. Applications: Water Tanks/Reservoirs, Boats/Marine Structures, Housing, Sculptures/Art Installations, Pipes/Culverts. Concept of Carbon Emission and its Reduction What Are Carbon Emissions? Release of carbon dioxide ($\text{CO}_2$) and other greenhouse gases (GHGs) into the atmosphere. Sources: Natural (plants, animals), Human (burning fossil fuels, manufacturing, transportation, deforestation). GHGs trap heat, leading to global warming, ozone layer deterioration, ecosystem destruction. $\text{CO}_2$ is the most prevalent GHG from human activity. Why Is Reducing Carbon Emissions Important? Save Lives: Improves air quality, prevents chronic health conditions and premature deaths. Ease Healthcare Burden: Reduces frequency of healthcare visits for chronic conditions. Reduce Wildfires: Breaks the cycle where emissions cause extreme weather (heatwaves) and wildfires emit more carbon. Ways to Reduce Carbon Emissions Reduce Air Travel: Transportation is a major source of GHGs; one transatlantic flight saves $\sim 1.6$ metric tons $\text{CO}_2$ equivalents/year. Plant Trees: Trees absorb and store $\text{CO}_2$; inexpensive, natural climate action. Switch to Clean Energy: Solar, wind, geothermal reduce dependence on fossil fuels. Eat Less Red Meat: Beef production is energy-intensive; $\sim 220$ grams $\text{CO}_2$ per gram of beef. Sector-Specific Strategies Energy Sector: Renewable Energy: Solar, wind, hydro, geothermal. Energy Efficiency: Better insulation, efficient appliances. Carbon Capture and Storage (CCS): Capture emissions from power plants. Transportation: Electric Vehicles (EVs): Promote adoption and infrastructure. Public Transportation: Invest and encourage use. Carpooling/Ridesharing: Reduce individual vehicle journeys. Industry: Energy-Efficient Technologies: In manufacturing processes. Waste Heat Recovery: Utilize generated waste heat. Material Efficiency: Recycling, sustainable sourcing. Buildings: Energy-Efficient Construction: Materials and technologies. Smart Buildings: Optimize energy use for heating, cooling, lighting. Green Roofs and Walls: Improve insulation. Agriculture: Sustainable Farming Practices: Reduce chemical use. Agroforestry: Integrate trees to sequester carbon. Precision Farming: Optimize resource use. Forestry: Afforestation and Reforestation: Plant trees. Sustainable Logging: Minimize deforestation. Forest Protection: Prevent illegal logging. Waste Management: Recycling and Composting: Reduce landfill waste. Waste-to-Energy: Convert waste into energy. Reducing Single-Use Plastics: Promote alternatives. Individual Actions: Energy Conservation: At home (appliances, lights, insulation). Reduced Meat Consumption: Plant-based diet. Sustainable Consumer Choices: Products with lower carbon footprint. Policy and Advocacy: Carbon Pricing: Incentivize emission reduction. Regulations and Standards: Strengthen emission regulations. International Cooperation: Address global challenges. Education and Awareness: Public Awareness Campaigns: On impacts and actions. Environmental Education: Integrate into curricula.