Cement and Concrete in Sustainable Housing

Transcription

1 Cement and Concrete in Sustainable Housing PPC Cement October 2011

2 Continuing the Story of. The three little pigs and

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4 Pretoria Portland Cement Founded in 1892 as De Eerste Cement Fabriken Beperkt and opens operations at Hercules in Pretoria Opens Slurry Factory near Mafikeng in PPC operates in South Africa, Zimbabwe and Botswana with a cement capacity of over 7 Million tons of cement and lime products 7 Cement Operations, a Slag Mill and the largest lime plant in the Southern Hemisphere Known in South Africa as The Passionate People s Company

5 Sustainable Human Settlements Social Housing is a focus area, but has been a great challenge in South Africa Creating Sustainable Social Housing is Key to climate resilience and goes much further than the carbon footprint of the development during construction. Social Housing must become climate resilient Climate Resilience Systems Thinking Integrated Developments Embodied vs. Life Cycle Energy Capital vs. Life Cycle Cost

6 Climate Resilience Salient Points from the Climate Change Green Paper Significant climate impacts Higher temperatures (3-6 C by 2100) Lower rainfall in some areas with higher rainfall in others Highly variable weather patterns (floods, droughts, fires, winds) Higher evaporation from dams Sea level rise

7 Climate Resilience Green Paper - Vulnerability SA is highly vulnerable to impacts of climate variability High levels of poverty SA MUST effectively adapt to and manage unavoidable and potential damaging climate change impacts through interventions that build and sustain South Africa s social, economic and environmental resilience and emergency response capacity

8 Climate Resilience Green Paper Response Sectors Water Agriculture Human Health Disaster Risk Management Natural Resource Protection Human Society and Livelihoods Energy Industry Transportation ADAPT MITIGATE

9 Climate Resilience The poor in South Africa face significant challenges related to climate change Affordable Housing and the related energy cost Historically poorly executed housing projects focused on up front cost management Focus on ability of building / structure to allow occupants to become more climate resilient Low energy usage Water resilient Able to withstand weather impacts

10 Cement, Concrete and CO2 in Perspective A typical ton of OPC 900 kg CO 2 e 1 typical 1m 3 of concrete 180 kg CO 2 e vs. Using 60 Litres of petrol in a car Replacing 9 lights with CFL s Average use of a home computer for a year vs 1 ton CO 2 e per person to fly from New York to London PCA Technical Brief

11 Comparative CO2e Footprint The Cement Sustainability Initiative Progress Report, WBCSD June 2005

12 Embodied Carbon Danish LCA databases, BEAT2002

13 Embodied Carbon

14 m 3 carbonated Embodied Carbon CO 2 uptake during lifespan of a structure DK (Glavind) % carbonated % carbonated years concrete produced 2003 life time after demolition The red column is total CO 2 emitted during calcination

15 The New PPC Surebuild 42.5N The new PPC Surebuild Cement 42,5 N with extra strength yields 15% more concrete.

16 Focus on sustainability A focus on all the elements that enhance sustainability is crucial to address the challenge C&CI Sustainability Brochure web.pdf

17 Systems Thinking Embodied Energy vs Life Cycle Energy C&CI Sustainability Brochure

18 The Cost of replacing only 1 out of 100 bridges far outweighs benefit of changing cement type in all Courtesy: Jørn Lauridsen, Danish Road Directorate

19 Life Cycle Thinking

20 Life Cycle Thinking Green structural and building design Recycled concrete aggregate Cement with reduced CO2 Phase 1 Raw materials. Phase 2 Production Supplementary cementitious materials Aggregates and admixtures CO2 uptake Energy Phase 4 Demolition Recycling Phase 4 Use, repair, maintenance Phase 3 Construction Environmental management Courtesy Santie Gouws, CSIR

21 Life Cycle Design We need a shift from structural design.. COST SAFETY SERVICEABILITY/ COMFORT Courtesy Santie Gouws, CSIR

22 Life Cycle Design..to designs for service life Lifetime Cost COST SAFETY SERVICEABILITY/ COMFORT Resilience to Climate Impacts Courtesy Santie Gouws, CSIR

23 Life Cycle Design..to designing for lifetime environmental performance Sustainable Low Cost Development Integrated Thinking Lifetime Cost COST SAFETY SERVICEABILITY/ COMFORT Resilience to Climate Impacts Lower Environmental Impact = Lower Lifetime Cost Courtesy Santie Gouws, CSIR

24 Energy - Thermal Mass Thermal Mass is the ability to store heat

25 Energy Solar Reflectance

26 Energy Solar Reflectance Concrete pavements reduce energy use in developments due to lower lighting requirements and lower AC cost

27 Energy Solar Reflectance Concrete Pavements lower lighting cost

28 Energy Solar Reflectance Concrete Road surfaces enhance road safety Before After

29 Water Concrete is crucial as normal water management, and storm water management, needs increase. The of pervious concrete and concrete water management structures improves water management

30 Human Society and Livelihoods Concrete is labour intensive

31 Close Focus less on climate resilience and not on carbon footprint at construction. Life Cycle Design and systems thinking Concrete and Concrete Products are key to sustainable construction