Optimizing Energy Efficiency During Integrated Design: A Whitehorse Case Study

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1 Optimizing Energy Efficiency During Integrated Design: A Whitehorse Case Study Northern Energy Solutions Conference 17 February 2010 Curt Hepting, P.Eng., P.E. EnerSys Analytics Inc. 1

2 Introduction Cost-effective methods exist for integrating energy efficiency into designs Integrated design produces more efficient, marketable buildings Many new buildings barely comply with energy codes (e.g., ASHRAE 90.1) Lost opportunities from taking standard approach to new building design 2

3 Why Don t We Design Energy Efficient/Sustainable Buildings? Focus on up-front costs Life-cycle cost-effectiveness ignored Design team squeezed on fees Owner does not pay the energy bills Scheduling constraints Fees tied to quantity instead of quality That s the way it s always been done Marketing perception vs reality 3

4 Approaches to Sustainable Design Integrated Design Environmentally Responsive Building Design Modelling Approach Design facilitation Iterative building energy modelling Meet... Model... Results... 4

5 Energy Performance Workshop Concept Exploration of energy-efficiency strategies during any design stage Focused on a key point of the design process Typically, a single intensive meeting Teams architects, engineers, cost consultant and sponsoring agency with energy analyst Allows for quick and educated decisionmaking 5

6 Energy Performance Workshop Process Data gathering Questionnaire / Correspondence Building plans Reference data Weather Project setup and modelling Energy performance workshop (EPW) Reporting & follow-up 6

7 What Happens During an EPW? Interactive working meeting Review design and pre-workshop model Energy efficiency measures Sensitivity analysis of design options LCC assessment / Cost-effectiveness screening Immediate feedback, including with compliance and program qualification indicators 7

8 Owner/Occupant Benefits of Integrated Design Design optimization Reduced energy and operating costs Potential to lower capital costs Increased potential comfort Increased marketability of building 3 rd party verification (e.g., LEED) Possible incentives 8

9 Consultant Benefits of Integrated Design Valuable information to assist with early decision-making process Forum for verifying savings from creative/atypical design solutions Opportunity to optimize systems Indicators as to impact on system capacities for right-sizing equipment Immediate feedback on most options (EPW approach) 9

10 Quantitative Results Case Study Whitehorse Public Safety Building, Yukon Territory 10

11 Whitehorse PSB: Background Firehall and Emergency Management Operations / By-Law Offices Two distinct functions and areas Floor area: 2790 m², m, including a 1380 m² m apparatus bay Steel structure for Bay, wood construction for office block Environmentally conscious design Life-cycle cost-effective Durability and longevity Energy efficiency 11

12 Whitehorse PSB: Baseline Review Building loads typically investigated first Influences mechanical system configuration and sizing Primary heating source can have a significant influence on bill savings Fuel Oil (typical) Ground source heat pump (mostly electric) 12

13 Whitehorse PSB: Baseline Review Building loads typically investigated first Influences mechanical system configuration and sizing Primary heating source can have a significant influence on bill savings Fuel Oil (typical) Ground source heat pump (mostly electric) 13

14 Whitehorse PSB: Baseline Review Annual Energy (GJ) 5,000 4,500 4,000 3,500 3,000 2,500 2,000 1,500 1, All Electric Heating Annual Utility Costs Reference (Electric) $180,000 $160,000 $140, % $120,000 $100,000 $80,000 $60,000 $40,000 $20,000 Baseline (GSHP) Whitehorse Public Safety Building Reference (Oil Boiler) Central Oil Boiler $5.14 All Electric Heating 31.1% 36.5% $ % $3.65 $3.59 $3.32 GSHP/Oil Boiler HP/Oil Boiler Reference (Elec/Oil) GSHP (Elec/Oil) 29.7% HP (Elec/Oil) $0 Cooling Heating Lighting Reference Equipment Baseline Reference Fans & Pumps GSHP/Oil DHWHP/Oil Ext. Reference Lts Elev. (Electric) (GSHP) (Oil Boiler) Percentages denote savings relative to the appropriate CBIP Reference Electric/Oil Boiler Plant Whitehorse Public Safety Building Central Oil Boiler Boiler Boiler $4.01 (Elec/Oil) Electric/Oil Boiler Plant $3.24 GSHP (Elec/Oil) Electric Energy Electric Demand Fossil (Gas) $3.46 HP (Elec/Oil) Costs above bars denote annual energy costs per square foot 14

15 Whitehorse PSB: Envelope Efficiency Measures Roof Increase insulation from R-40 to R-60 (>25 yr LCC payback, simple) R-100 insulation (16 10 yr)* Double Bay insulation to R-40 (18 7 yr)* Walls Several insulated stud build-out configurations (>25 yr LCC paybacks, best at 4.6% IRR*) Double Bay wall insulation (22 9 yr)* Foundation insulation optimization (>25 14 yr*) 15

16 Whitehorse PSB: Window Measures Frame Options Vinyl vs aluminum (>25 yr payback)* Fiberglass sensitivity Glazing Units Triple pane low-e (2.6 yr payback max)* Warm edge spacer (9 yr max)* Translucent panel clerestoreys (>25 yr) 16

17 Whitehorse PSB: Lighting Measures Connected Load LPD reduced from W/ft² (instant payback)* Automated Controls Occupancy sensors (6 yr)* Office daylight harvesting (>25 year) Bay daylighting (0.3 yr)* Remove Bay daylighting and clerestories (<3 yr for baseline) 17

18 Whitehorse PSB: Mechanical - Ventilation Measures SolarWall Reverse Flow Exhaust Heat Recovery Reverse-Flow diagram from RegentEco brochure 18

19 Whitehorse PSB: Mechanical - Ventilation Measures Heating of Fresh Air SolarWall on Bay (18 10 year payback)** Reverse-flow exhaust heat recovery (5 8 yr)* Reverse-flow + SolarWall (6 9 yr) SolarWall incrementally >25 year payback; possibly as low as 18 years with Federal grant Heat pipe later retained; hence, SolarWall costeffectiveness would improve Automated Controls CO2 demand control ventilation (>25 6 year payback)* 19

20 Whitehorse PSB: Mechanical Ground-Source Heat Pump Sizing at 50% & 25% of peak load (instantaneous payback) GSHP not cost-effective (over 50-yr simple payback)* 20

21 Whitehorse PSB: Mechanical DHW and Renewable Measures Domestic Hot Water GSHP preheat (5 year payback) Flat plate solar water heating (>25 yr) Other Renewable Photovoltaics (68 year simple payback) 21

22 Whitehorse PSB: Proposed Workshop Design Annual End-Use Energy Use Comparison 22

23 Whitehorse PSB: Proposed Workshop Design Annual Utility Cost Comparison 23

24 Whitehorse PSB: Proposed Workshop Design Annual Savings vs. Baseline GSHP Design MJ/m² ( Btu/ft²) 24-25% $ /m² ($ per ft²) 37% Capital cost reduction of $920, ,000 (instantaneous payback) Annual Savings vs. MNECB (LEED) Reference MJ/m² ( Btu/ft²) 54% $ /m² ($ per ft²) 50-51% regulated end-use savings Equivalent to 6 LEED Canada EAc1 points Adoption of at least 14 measures Reverse-flow heat recovery scaled back since Workshop 24

25 Keys to Success Receptive and flexible design team, including owner Recognize value of process Communication! Quick and timely feedback Energy model and meeting preparation Appropriate level of detail 25

26 Conclusion Energy performance workshop as a key component of integrated design Provides for informed decisions to help form a business case for energy efficiency Enhanced speculation on energy issues Substantiation of efficiency strategies Secondary benefits (marketability, code compliance, emissions reduction, etc.) 26

27 Thank you! 27