Re-Commissioning Buildings

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RECOMMISSIONING:

The Low Cost Way to Improved Building Performance

CaGBC Building Advisor ProgramOctober, 2012John Kokko, P.Eng., CCP, LEED APjkokko@enermodal.com519-743-8777 x2424

RECOMMISSIONINGLearning Objectives

► Understand the RCx process► Appreciate RCx costs and

benefits► Know how to prepare RCx

goals and objectivers► See how RCx fits within LEED

EB: O&M

RECOMMISSIONINGWhat is Building RCx

► Taking existing building systems and getting them working as best they can

► A systematic process for review and implementation of mainly operational improvements

► Bring building performance in line with current requirements and expectations

RECOMMISSIONINGWhat Does RCx Do?

► Reviews all building energy related systems including:

► Controls, HVAC, Building Envelope, Electrical, Plumbing

► Improves the operation of existing systems and equipment

► Includes implementation of low cost / no cost measures

► Identifies capital cost improvements► Provides both energy and non-energy

benefits

RECOMMISSIONINGWhy RCx?

► Higher than acceptable energy costs

► Escalating maintenance costs

► Significant occupant complaints

► Building use has changed

► Building is > 5 years old with no RCx

► Retrofits have been made with no RCx

► Staff turnover with minimal training of new staff

RECOMMISSIONINGRCx vs. Energy Audit

RECOMMISSIONINGSample RCx Findings

RCx opportunities found during walk-through:► Outdoor air on rooftop at 80% when it should be 20%► Heating coil and cooling coil operating simultaneously► RTU constantly cycling between heating and cooling► VFD pump with throttled discharge valve► Lighting and ventilation on in the middle of the night► Building doors blowing open due to over-pressurization► Piping that was hot when it should be cold► 3 compressors turning on and off simultaneously► Water storage tanks set higher than boiler output► Humidifier dumping water whenever setpoint reached

RECOMISSIONINGRCx Process in a Nutshell

Planning Phase:► Pre-Screening: Benchmarking, selecting building(s), defining goals

& objectives► MILESTONE: Approval to proceed to Scoping

► Scoping: Select RCx provider, preliminary investigation, RCx plan► MILESTONE: Approval to proceed to Investigation Phase

Investigation:► Kick-off, in-depth investigation, document findings and present

recommendations► MILESTONE: Approval to proceed to Implementation Phase

RECOMISSIONINGRCx Process in a Nutshell

Implementation:► Implementation plan, implement measures, verify improvements

► MILESTONE: Owner accepts Implementation Report

Hand-Off:► Final RCx report, on-going / next RCx plan, staff training

► MILESTONE: Provider holds Hand-Off Meeting

Finally:► Persistence measures and long-term benchmarking

RECOMISSIONINGInformation and Materials

Recomissioning Guide for Building Owners and Managers canmetenergy.nrcan.gc.ca/eng/rcs.html

► Recommissioning Guide► Pre-Screening Tool► Benchmarking Tool► Case Studies

Other Resources:► Peci.org/resources/commissioning.html► ASHRAE► LEED EB: O&M

MMM GROUP LIMITED

PLANNING

RECOMMISSIONINGIdentify Candidate Building

RECOMMISSIONINGSet RCx Goals and Objectives

Energy Issues:► Reduce energy consumption by

15% annuallyIEQ Issues:► Reduce occupant comfort

complaints by 50%Operational Issues:► Update O&M documentation and

provide staff training, needed to maintain performance

MMM GROUP LIMITED

INVESTIGATION

RECOMMISSIONINGBenchmarking – Energy Star

RECOMMISSIONINGUtility Bill Breakdown

Two years utility data

Modeling used to identify load breakdown

Base Case Energy End Use

Exterior Electric (1%)

Electric Hot Water (3%)

Fan Electric (6%)

Lights (14%)

Cooling Electric (19%)

Plug Loads (22%)

Space Heat Electric (35%)

RECOMMISSIONINGEnvelope Air Tightness and Thermal Bridging

RECOMMISSIONINGLighting

► Indoor lighting 2x4 T-12 Troffers at 2.4 W/ft2 with minimal zoning. Discoloured lenses , low light levels

► Outdoor lighting and signage remains on 24 hr/day due to malfunctioning timer

RECOMMISSIONINGHVAC

► Electric heaters in ceiling space above boardroom and other offices on 3rd floor running continuously

► Economizer not operational due faulty to sensor and broken damper linkage

RECOMMISSIONINGAir and Heat Delivery

► Non-powered diffusers, some inoperable, others mismatched masters and slaves

► Electric baseboard heaters operating at the same time as cooling due to excessively high t’stat control setting

Electricity Retrofit Incentive Program (ERIP) – OPA► For retrofit of existing facilities focuses on lighting, motors, HVAC

and overall electricity savings► Chiller Re-Commissioning

Enbridge Gas Retrofit Incentives ► Provides up to $0.10 per m3 of natural gas saved for saving

measures based on projected first year gas savings.

Union Gas Run it Right► Provides 100% of implementation costs up to $5,000 ► Plus up to $3,000 to provide monitoring showing savings

RECOMMISSIONINGIncentives

RECOMMISSIONINGNext Steps

► Review of recommendations, costs, and paybacks with owner

► Owner decides which options to accept and which to reject

► Has hired 3rd party PM firm to oversee installation ► Next steps will be retrofit of lighting, air handlers, and

other capital cost items► RCx will then include Cx of newly installed systems

and remainder of RCx items

MMM GROUP LIMITED

COSTS AND BENEFITS

RECOMMISSIONINGApproximate RCx Costs

► Planning ~$5,000 to $8,000► Investigation, Implementation, and Hand-off $1.40 to $10.84/m2 for the

total RCx process depending on:

► External consultant costs range from 35% to 71% of total costs

Building size Complexity of systems Up-to-date

Documentation BMS data availability

Project scope Subcontractor requirements Implementation involvement Owner involvement

RECOMMISSIONINGIssues Identified with RCx

Top Cumulative Savings Measures and % of Savings

Key Measure Mix % of Total SavingsRevise control sequence 21%

Reduce equipment runtime 15%Optimize airside economizer 12%

Add / optimize SAT reset 8%Add VFD to pump 6%

Reduce coil leakage 4%Reduce / reset DSP setpoint 4%

Add / optimize optimum start/stop 3%

Add / optimize CWST reset 2%A study on Energy Savings and Measure Cost Effectiveness of EBCx

Portland Energy Conservation, Inc. Dec 15th, 2009

RECOMMISSIONINGApplicability of RCx Measures

Comparison of key measure mix to building attributesBuilding Attribute

Sub-CategoryPercent of savings achieved

through key measure mixBuilding TypeLarge Office 72%Hotel/Motel 64%

Building Size0-200 73%

200-350 55%350-550 69%

>550 69%Building Age

<1920 63%1980-1989 72%

2000-Present 71%Climate Zone

3B 77%3C 78%

RECOMMISSIONINGEnergy Savings and Payback

RECOMISSIONINGAdditional RCx Benefits

Protect of enhance property value:► Maintain high occupancy rates► Reduce tenant turnover► Gain marketplace competitive edge

Protect against future liability:► Reduce potential for sick building syndrome► Identify and address indoor environmental issues

Reduce repair and replacement costs:► Increase equipment life► Reduce maintenance requirements► Reduce comfort complaints

RECOMMISSIONINGValue of Non-Energy Impacts

For typical commercial buildings≈ $1.61 to $3.23/m2

Median value:$1.94/m2

Range:$1.08 - $4.84/m2

17%21%

Liability (1%)

Change Orders & WarrantyClaims (5%)Productivity/Safety (5%)

Ongoing Labour Cost (7%)

Other First Cost (10%)

Indoor Air Quality (17%)

Thermal Comfort (21%)

Equipment Life (33%)

Reported NEIs for 36 projects in existing buildings (USA)

Source: Lawrence Berkeley National Laboratory, “The Cost Effectiveness of Commercial-Buildings Commissioning,” December 2004.

MMM GROUP LIMITED

OTHER CASE STUDIES

RECOMMISSIONINGOffice Tower - Winnipeg

Courtesy NRCan: www.canmetenergy.nrcan.gc.ca/eng/rcx.html

RECOMMISSIONINGAdult Ed Centre, Sherbrooke, QC

RECOMMISSIONINGCase Studies

Savings Items Office Winnipeg Ed Center Sherbrooke

Energy Savings1 (GJ/yr, %) 6,652 GJ (25%) 763 GJ (12%)

% Natural Gas; % Electricity 75% NG; 25% E 84% NG; 16% E

Financial Savings2 ($/yr) $59,000/yr $13,300/yr

GHG Reduction (t CO2 e/yr) 363 t/yr(66 cars)

42 t/yr(8 cars)

Simply Payback3 (yr) 3.3 yr 3.9 yr

1 Savings verified 12 months after implementation of the RCxmeasures and weather-normalized.

2 Monetary savings don’t include non-energy impacts (NEIs) such as equipment durability or reduction of tenant complaints.

3 Includes all 4 phases costs of project

RECOMMISSIONINGCase Studies

Adult Ed Centre

Sherbrooke, QC

Office Tower

Winnipeg, MB:

RECOMMISSIONINGTop RCx Tasks

► 1. Turn off equipment that should be off► Over-ridden schedules, systems

set for 24/7 operation► Broken or out of calibration timers► Poor original sequence► Optimum start/stop not working► Equipment set to operate in

HAND rather than Auto

► 2. Improper ventilation / outdoor quantities► not set to match current

requirements

► 3. Verify dampers and valves on central AHUs operating property► Sticking due to long time

non-use► Broken or damaged linkages► Improper repairs

► 4. Verify terminal units operating properly► Inoperative actuators / valves► Defective receiver/controller► Out of calibration sensors► Deficient or excessive flow► Dirty rads or coils not heating

the space► Malfunctioning secondary

loop temperature control

► 5. Verify Supply Static Pressure Setpoint (Air and Water Systems)

► 6. Verify Supply Air and Water Temperature Reset Schedule

► 7. Eliminate Simultaneous Heating and Cooling

► 8. Return VFD to Variable Speed Operation

► 9. Calibrate Sensors and Instrumentation

► 10. Interference with Room Controls

MMM GROUP LIMITED

RCx and LEED EB:O&M

RECOMISSIONINGRCx and LEED EB:O&M

EAp1: Energy Efficiency Best Practices Management :

► Planning, Documentation and Opportunity Assessment

EAp2: Minimum Energy Efficiency Performance► EAc2.1: Existing Building Commissioning:

Investigation and Analysis (2 points)► EAc2.2: Existing Building Commissioning:

Implementation (2 points)► EAc2.3: Existing Building Commissioning:

Ongoing Commissioning (2 points)

RECOMMISSIONINGEAp1: Planning, Documentation, and Opportunity Assessment

► 1. Building Operating Plan► 2. Systems Narrative► 3. Sequence of Operations► 4. Preventative Maintenance

Plan► 5. ASHRAE Level I Audit

► Utility Bills review► Energy Utilization Index► Low Cost/No Cost

Improvements

RECOMISSIONINGEAp2: Minimum Energy Efficiency Performance

Option A:► Energy Star® : Energy Performance Rating min 69

Option B:► 19% better efficiency than cohort average

RECOMISSIONINGEAc2.1: Investigation & Analysis

Option A – Commissioning Process:► Site Assessment► Building Energy End-Use Breakdown► Diagnostic Monitoring And Functional Testing► Master List Of Findings

Option B:► ASHRAE Level II Audit► Building Energy End-Use Breakdown► Cost - Savings Analysis► Listing of capital improvements

RECOMISSIONINGEAc2.2: Implementation

1. Implement low cost / no cost measures

2. Provide building staff training

3. Provide the following documentation:► Listing of measures, operational improvements and/or

repairs implemented► Update or revise the Building Operating Plan► Recommended capital plan for major retrofits or

upgrades► Summary of staff training program

RECOMMISSIONINGEAc2.3: Ongoing Commissioning

1. Update the Systems Manual

2. Produce an On-Going Commissioning Plan

3. Implement Ongoing Commissioning

RECOMMISSIONINGConclusions

► RCx is a systematic process that optimize comfort and energy savings of existing buildings

► RCx can reduce whole-building energy uses by 5% to 30%

► Paybacks typically in the 0.5 to 5 yr range► RCx helps the persistence of energy and non-energy

benefits ► RCx can help obtain LEED EB:O&M Certification

MMM Group Limited100 Commerce Valley Drive WestThornhill, ON Canada L3T 0A1t: 905.882.1100 | f: 905.882.0055e: mmm@mmm.ca

Re-Commissioning Buildings

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