Presentation on theme: "MIT Concrete Sustainability Hub Bruce McIntosh, Portland Cement Association."— Presentation transcript:
MIT Concrete Sustainability Hub Bruce McIntosh, Portland Cement Association
Topics HUB background Life-cycle assessment of pavement Life-cycle assessment of buildings and homes Econometrics Green concrete science
MIT Concrete Sustainability Hub Established by PCA and RMCREF $10 million investment over next 5 years Validate and innovate: –Identify areas in which concrete excels –Identify opportunities for improvements –Create solid technical basis for future industry development
R&D Platforms Concrete Science Building Technology Econometrics
Concrete Science Platform Mission: Scientific breakthroughs toward reducing CO 2 footprint of cement and concrete Breakthroughs would imply: –Strength with less material –Lower energy processing –Chemical stability
Building Technology Platform Mission: Life-cycle assessment (LCA) of concrete buildings and pavements to identify impacts and opportunities
Econometrics Mission: Assess the impact on jobs and the economy of sustainable advancements in cement and concrete
Building Technology: Paving 8 million lane- miles 3 trillion vehicle- miles / year 27% of U.S. GHG emissions from road transportation
Indirect impacts Traffic delays Additional materials and energy Construction equipment emissions Material waste
Key findings Whole life LCA needed to capture all impacts Use and maintenance phases account for 33% to 44% of CO2 for interstate highways
Pavement-Vehicle Interaction Demonstrates of fuel savings with concrete Two factors: stiffness and roughness Stiffness Roughness
Stiffness or Deflection Rigid pavements produce less rolling resistance and better fuel economy Stiffness
Stiffness or Deflection Asphalt roads need to be 25% to 60% thicker to achieve same fuel efficiency as concrete. Goal is to assess impacts of pavement properties on fuel consumption for both environmental impact and cost savings.
Building Technology: Structures Life-cycle analysis research for single-family housing, multifamily housing, and commercial structures
Residential Bldgs Commercial Bldgs Industry Transportation 21% 18% 35% 26% United States Other of G7 countries Rest of the world 25% 19% 56% Why are Buildings Important?
Buildings Life-Cycle Analysis Examining materials within whole building context, not just manufacturing and initial construction Consider use and operations phases
Single-Family Housing Single family homes represent 80% of total residential energy consumption 80% Single family Multi-family
Single-Family LCA Exterior walls Wood frame and insulating concrete forms Quantity of insulation Thermal mass
Key Findings Concrete homes produce 5% to 8% lower GHG emissions. Concrete homes use 8% to 11% less energy. Concrete wall systems have higher embodied energy, but that accounts for only 2% to 12% of GHG over a 60-year service life.
Next Steps: Air Tightness Not considered in initial study, but represents greatest potential for additional improvement Improvement from average to tight saves 23% of total operating energy
Commercial Buildings Commercial buildings represent 18% of U.S. energy consumption
Commercial LCA Compares steel and concrete structural frames Floor to floor heights identical 12-story building with 40% glazing 12-
Key Findings No greater embodied energy than comparable steel frames Energy savings when concrete frame is exposed are 3%; when covered by finishes, 2%. Active use of the thermal mass capability of concrete slabs could result in significant savings
Econometrics Study on life-cycle cost analysis” for highways, “The Effects of Inflation and Its Volatility on the Choice of Construction Alternatives.” Study examines historical data on real prices of construction materials.
Key Findings Traditional analysis uses the same escalation rate for concrete and asphalt. Assumption of constant real costs can lead to serious cost overruns. Study suggests the use of material- specific escalation rates.
Advocacy and Promotion Working with state and federal officials to incorporate MIT findings in life-cycle analysis models Focus of ad campaign Goal: Level playing field for concrete and asphalt.