LEED Commissioning and Actual Energy Use. John Kokko, P.Eng. LEED A.P. Vice President Enermodal Engineering

Size: px

Start display at page:

Download "LEED Commissioning and Actual Energy Use. John Kokko, P.Eng. LEED A.P. Vice President Enermodal Engineering"

Myron Reynold Hill
6 years ago
Views:

1 LEED Commissioning and Actual Energy Use John Kokko, P.Eng. LEED A.P. Vice President Enermodal Engineering

AIA Quality Assurance Learning Objectives 1. Why Best Practice and Fundamental Commissioning are necessary for LEED buildings to achieve their energy savings potential. 2.

2 AIA Quality Assurance Learning Objectives 1. Why Best Practice and Fundamental Commissioning are necessary for LEED buildings to achieve their energy savings potential. 2. How well LEED buildings meet their predicted energy savings before and after commissioning. 3. The LEED commissioning process from design through postoccupancy as well as common design and construction mistakes found in LEED buildings by commissioning agents.

3 John Kokko, P.Eng. LEED A.P. Vice President of Enermodal Engineering Division Head, Building Commissioning

Commissioning Experience Background Over 20 years experience in building design, research and commissioning (>80 buildings) o Offices in Kitchener, Calgary, Denver, and Toronto o Largest consulting

4 Commissioning Experience Background Over 20 years experience in building design, research and commissioning (>80 buildings) o Offices in Kitchener, Calgary, Denver, and Toronto o Largest consulting firm in Canada exclusively dedicated to creating green buildings Services: o LEED design and certification o Energy analysis and modeling o Measurement & verification o Green building research o Sustainable building design facilitation o Mechanical/electrical design o Building commissioning

5 LEED Leadership in Energy and Environmental Design o Point-based green building rating system by US Green Building Council o At least 26 of 70 points (related to environmental issues) must be achieved for certification

LEED and Commissioning EAp1 Fundamental Commissioning EAc1 Enhanced (Best Practice) Commissioning o Up to 10 LEED points available for energy efficiency in the design

6 LEED and Commissioning EAp1 Fundamental Commissioning EAc1 Enhanced (Best Practice) Commissioning o Up to 10 LEED points available for energy efficiency in the design o Savings are predicted through energy modeling during design rather than actual o LEED recognizes commissioning necessary for buildings to attain performance potential

Traditional Commissioning Traditionally contractors/manufacturers start-up an individual piece of equipment and verify that it alone functions properly Neither the manufacturer nor the contractor

7 Traditional Commissioning Traditionally contractors/manufacturers start-up an individual piece of equipment and verify that it alone functions properly Neither the manufacturer nor the contractor is responsible for effective system operation Boiler s job is to make hot water, not to keep the building warm Control s job is to open/ close valves, speed-up slow down fans not minimize energy use

8 LEED and Commissioning Fundamental Commissioning Happens almost exclusively in the construction phase Installation inspections and equipment start-up Functional performance testing Ensure designed building is delivered

9 LEED and Commissioning Enhanced Commissioning Includes all phases: design, construction, and occupancy Independent design phase peer reviews Shop drawing reviews Commissioning continues one year after occupancy

10 Why is Commissioning Necessary? Don t designers and contractors commission? Designers meet code and They do professional best to meet owner s desires Contractors verify component, not system function No one guarantees performance North American construction process Low cost bids Nebulous performance targets Value engineering Fast-tracked construction Additional services resisted

11 Why is Commissioning Necessary? Increasingly complex systems Many new systems not well understood Manufacturer s technical agents, sales engineers, designers, contractors, and operators all have decreasing levels of knowledge Commissioning helps overcome these problems Qualified Commissioning Agent (CxA) works with all parties, through all phases CxA works with all parties to overcome difficulties CxA on behalf of the owner

12 Common Problems Discovered

Enhanced Cx Problems Discovered Specifying a condensing boiler but designing for high temperature radiation so there is no condensing and no savings Specifying VFD pumps with 3-way valves on loads so

13 Enhanced Cx Problems Discovered Specifying a condensing boiler but designing for high temperature radiation so there is no condensing and no savings Specifying VFD pumps with 3-way valves on loads so there is no turn down when terminal unit flow stops Main heating boilers used for summer DHW production with high standby losses and low efficiency HRV/ERV cold side ducts not fully insulated or sealed

Design Findings with Cost Savings Equipment sizing based on actual building U-values to right size equipment Increased temperature drops reduce pipe and pump sizing.

14 Design Findings with Cost Savings Equipment sizing based on actual building U-values to right size equipment Increased temperature drops reduce pipe and pump sizing. Increase in terminal unit sizing is required Removal of heat exchangers where they are not actually required Using passive heat recovery and proper pool air temperature control for humidity control rather than mechanical refrigeration equipment

15 Sisters of St Joseph Residence 126,000 ft 2 residence for retired Sisters in London Includes: chapel, cafeteria, commercial kitchen LEED Services Included LEED Consulting & Energy Simulation, Commissioning (F + BP) & M&V

16 HVAC System Features Central air handler with Energy Recovery Ventilators (ERVs) for common areas Kitchen air handler for heating, cooling, and ventilation Water loop heat pumps for space heating & cooling And individual Heat Recovery Ventilators (HRVs) in residences 63 x 328 ft deep ground-coupled boreholes Back-up boilers for loop and other loads

17 Sisters of St Joseph Residence HVAC System

18 Sisters of St Joseph Residence Other Features: Condensing gas-fired water heater High efficiency lighting with occupancy sensors Well insulated envelope & high performance windows

19 Design Phase Review Findings Removal of HX between building loop and ground loop reduced capital cost and increased efficiency Building loop heat injection moved to after rather than before the ground loop connection eliminated paying to heat the ground Removing DHW production off main boiler loop allowed large boilers to be shut off in summer and allowed temp reset and condensing Lowered rain water cistern fill level sensor located near the top of the cistern to near the bottom

20 Sisters of St Joseph Residence Shop Drawing Review Findings 3 re-submittals of heat wheel shop drawings required before a workable defrost strategy provided Shop drawing coil performance based on water while construction drawings show system will use propylene glycol Coils have greater water-side pressure drop than specified Controls sequences were carbon copy of engineer s general wording rather than converting to specifics that can be programmed

21 Sisters of St Joseph Residence Actual vs. Simulated Performance Annual Energy 150 ekwh/m Simulated Actual 0 Floor Area = m 2 Aug '04 (SL) Feb '06 (CBIP) Aug '06 (Review) Aug '07 to Feb '08 LEED Status: Gold LEED Energy Savings: 52% (7 pts)

22 TRCA Restoration Services Building 11,000 ft 2 office and workshop in Toronto LEED Services Included LEED Consulting & Energy Simulation Commissioning (F) & M&V M&E Design

23 HVAC System Features Geothermal heat pump loop Two-pipe hydronic heating and cooling Central HRV with earth-tube inlet Radiant floor heating and tempering during cooling (to avoid condensation) Fan coils for cooling

24 TRCA Restoration Services Building HVAC System

25 TRCA Restoration Services Building Other Features: 2.5 kw photovoltaic array (grid-connected) High efficiency lighting with daylighting controls Well-insulated envelope & high performance windows

26 TRCA Restoration Services Building Functional Performance Test Findings CROSSED FLOOR LOOPS Office thermostat controlling floor heat in storage room. Storage room hot, office cool DEFECTIVE HEAT PUMP Supplier blamed low system flows but would not measure. Cx measurements showed water flows ok. Heat pump diagnostics finally found faulty TX valve and low refrigerant SEQUENCE ERRORS Controls are single most important item in ensuring successful system operation for comfort and energy savings

27 TRCA Restoration Services Building Actual vs. Simulated Performance 250 Annual Energy ekwh/m Simulated Actual Floor Area = 1037 m 2 Feb '05 (SL) Mar '05 (SL) Aug '06 (CBIP) Feb '07 (Review) May '07 to Apr '08 LEED Status: Platinum LEED Energy Savings: 65% (10 pts)

28 Comparisons Actual Energy Use Compared To Typical Buildings Annual Energy ekwh/m All Bldgs C&I Accom Offices Offices SSJ TRCA (ON) (ON) (ON) (CAN)

29 Conclusions Commissioning important part of buildings meeting their energy targets. Commissioning has an integral role in ensuring buildings operate as intended with comfort levels and energy savings expected. Comprehensive full-service LEED commissioning including Fundamental and Enhanced Commissioning indispensible on high-performance buildings

30 AIA Quality Assurance Portland Energy Conservation, Inc is a registered provider with The American Institute of Architects Continuing Education Systems. Credit earned on completion of this program will be reported to CES Records for AIA members. Certificates of Completion for non-aia members are available on request. This program is registered with the AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.

31 John Kokko

LEED Commissioning and Actual Energy Use

LEED Commissioning and Actual Energy Use John Kokko Enermodal Engineering Synopsis This paper follows two case studies through full LEED Best Practice and Fundamental Commissioning. It uses the original