Multi-objective building envelope optimization for life-cycle cost and global warming potential ECPPM 2012Forest Flager, John Basbagill, Michael Lepech, and Martin Fischer

Outline Motivation Method 2 Case Study 3 Scope 1 4 Results 5 Conclusions 6 Flager, Basbagill, Lepech, Fischer ECPPM of 15

Conceptual Design Development Construction Administration Operation Ability to impact cost Cost of design changes Traditional design process Preferred design process Design Stage Impact Motivation 1 Flager, Basbagill, Lepech, Fischer ECPPM of 15

perception: LCC and LCA require highly detailed understanding of building components CAD tools lack interoperability with analysis tools energy simulation tools designed for post-design process buildings are unique Challenges with integrating LCC and LCA during conceptual building design: Motivation 1 Flager, Basbagill, Lepech, Fischer ECPPM of 15

5 Building material production Transportation On-site construction Operation Demolition Maintenance, Repair, & Replacement Raw material acquisition Scope: Life-Cycle Cost and Carbon Footprint 2 Flager, Basbagill, Lepech, Fischer ECPPM of 15

6 Building information model Pre- operational cost Optimizer MRR schedule Pre- operational CO2e Energy simulation Operational cost Operational CO2e Life-cycle cost Life-cycle CO2e KEY Automated data translation DProfiler SimaPro eQUEST CostLab Excel ModelCenter Method: Multi-disciplinary Design Optimization 3 Flager, Basbagill, Lepech, Fischer ECPPM of 15

Beck Technology Innovation in all Dimensions Case Study: Research Collaboration 4 7 of 15

8 Case Study: US Government Building, Atlanta Area 4

9 SCOPE (1) Facade (2) MEP system OBJECTIVES (1) Minimize total cost of ownership (2) Minimize carbon footprint VARIABLES (1) Building orientation: ° (2) Glazing type: 7 options (3) Glazing percentage by façade: 30-70% DESIGN SPACE Possible design configurations: 8.73E8 Design Problem 4 Flager, Basbagill, Lepech, Fischer ECPPM of 15

10 Design Problem: Assumptions 4 Flager, Basbagill, Lepech, Fischer ECPPM stories 23,000 m 2 Service life: 30 years Floor-to-floor height: 5.0 m Floor plates: slab on metal deck supported by steel frame Mechanical system: VAV forced air cooling: direct expansion coils heating: central furnace Electricity: Cost: $0.10/kWh Impact: kg CO 2 e/kWh Natural gas: Cost: $0.015/kWh Impact: kg CO 2 e/kBtu 10 of 15

11 KEY Baseline Lowest Cost Lowest Carbon Life-cycle Cost (USD, millions) Preference Shading Best Results: Life Cycle Cost vs. Carbon Footprint 5 Best Worst Flager, Basbagill, Lepech, Fischer ECPPM of 15

12 facade glazing % N S E W Lowest Carbon objective Lowest Cost 30% 31% 30% 68% 59% 68% 55% 36% 30% 3% 15% KEY Baseline orientation +6.6° +6.7° +7.1° 0° orientation + cladding type VNE VS 1-08 Solarban 70 XL 39% VNE 1-63 escalation - - spandrel Results: Optimal Design Configurations 5 Flager, Basbagill, Lepech, Fischer ECPPM of 15

13 COST SAVINGS (NPV, USD) *BaselineNPV CO 2 e KEY +6.6°+6.7° +7.1° 0° $500K $1,000K $1,500K $2,000K -$500K +$624K +$839K +$1,729K 3%15% objective orientation escalation - - MEP Capital + MRR Cladding Capital Operational Energy Results: Cost Savings 5 Flager, Basbagill, Lepech, Fischer ECPPM 2012 *Baseline cost: $16.6 M 13 of 15

14 CARBON REDUCTION (ton CO 2 e) -2,000 1,000 2,000 3,000 -3,000 +4,300 -1,000 4,000 5,000 -1,063 +4,191 MEP Embodied Energy Cladding Embodied Energy Operational Energy KEY *BaselineNPV CO 2 e objective orientation +6.6°+6.7° +7.1° 0° escalation 3%15% - - Results: Carbon Reduction 5 Flager, Basbagill, Lepech, Fischer ECPPM 2012 *Baseline carbon impact: 60,900 tons CO 2 e 14 of 15

15 Conclusions Proposed MDO method improves conceptual building design 20% of designs improved both cost and carbon impact $800K cost reduction (5.1% < base design) 4,300 kt CO 2 e carbon savings (7.1% < base design) Limitations Building components: envelope and MEP systems Life cycle: upstream phases, operation, MRR Parameters: façade, glazing, orientation structural and interior components, foundation construction, transportation, demolition massing: building shape, # floors structural system 6 Flager, Basbagill, Lepech, Fischer ECPPM of 15

Questions? Flager, Basbagill, Lepech, Fischer ECPPM 2012