Retro-Commissioning - NFMT · Retro-Commissioning •California Commissioning Collaborative:...

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The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Retro-Commissioning:

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Getting the most from your buildings

Dan Brown

PE, CCP, CEM, LEED-AP THE STONE HOUSE GROUP

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

2

• Founded in 1999 on three pillars of

facilities management: operations, technical services and finance

• Dedicated to strengthening the mission and unique needs of our clients

• Focus on facilities

and technical services

progressed to include

sustainability consulting

Company Profile

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Retro-Commissioning

• What is retro-commissioning?

• Why is it done?

• How is it done?

• When is it a good idea?

3

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

What is Commissioning?

• Building commissioning (new construction)

• Retro-commissioning

• Recommissioning

• Continuous commissioning

4

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

New Building Commissioning

• Commissioning: – A systematic process to ensure the design,

installation and operation of systems meet the owner’s project requirements

• Key elements: – Design review

– Installation inspections

– Functional testing

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The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

New Building Commissioning

• Timeline – Ideally begins early in design phase

– Should cover occupancy and warranty period

• Scope – Minimum of energy-consuming MEP systems

– Can include fire protection, communications, envelope, security or other systems

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The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

7

Commissioning provides continuity, bridging the gaps between different phases of construction from OPR through occupancy

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

New Building Commissioning

• Process commissioning: – CxA develops installation checklists &

functional forms

– Contractor fills out forms and performs tests

• Technical commissioning: – CxA develops installation checklists &

functional forms

– CxA inspects installation and performs functional performance testing

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The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

New Building Commissioning

• Equipment startup is not commissioning – Startup:

• Does the chiller run?

– Commissioning • Should the chiller be running? • How do I maintain the chiller so it keeps running? • At what load should the chiller be running? • Is this the best chiller to use? • Is the chiller running efficiently? • Is the chiller having the desired effect on integrated

systems and space conditions? 9

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

10 Installation does not always meet the design intent

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Retro-Commissioning

• California Commissioning Collaborative: – Retrocommissioning is a process that seeks

to improve how building equipment and systems function together … Retro-commissioning improves a building's operations and maintenance (O&M) procedures to enhance overall building performance.

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The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Cx vs RCx: Approach

• Retro-Commissioning: – Uses technical approach

– Focuses on energy, comfort issues

– Mostly control improvements

– Compares current operation to current and future facility needs

– Fast payback items

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The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

13

Frequency of Implemented Measures in RCx Projects

Average Simple Payback (Years) by Type

Data Source: Mills, E., 2009. “Building Commissioning: A Golden Opportunity for Reducing Energy Costs and Greenhouse Gas Emissions”

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Cx vs RCx: Resources

• New building commissioning:

Owner’s Rep, Engineer, General Contractor, Subcontractors

Drawings, submittals, as-builts, O&Ms, RFIs, ASIs, OPR, BOD 14

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Cx vs RCx

• Retro-commissioning resources:

Limited or no engineer, GC or contractor availability

Whatever documents are available

Facility staff and occupants 15

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Why Retro-Commission?

• High operating cost – Building energy cost

– Maintenance & service calls

– Equipment life cycle

• Optimized runtime

• Ladder of reactive, preventive, predictive maintenance

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The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Why Retro-Commission?

• Comfort control – Space temperature too hot or cold

– “Stuffy” air; poor ventilation

– Drafts or pressurization issues

– Poor controllability

– Moisture or mold potential

• Code requirement – Sector (eg hospitals)

– Local code 17

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Why Retro-Commission?

• Changes to space use

• Adjustments to building systems

• Improve sustainability

• Marketing edge and improved image

• Building was never commissioned

• Over 5 years since recommissioning

• Increase building value 18

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Why RCx: Energy Cost

• O&M Best Practice Guide: – 5%-30% energy reduction

– Simple payback typically less than 2 years, often less than 0.5 years

• DOE – Typical energy cost over $2/GSF

– Typical RCx savings of 10-20%

– RCx median cost of $.30 per GSF (2009)

– Typical payback slightly over 1 year 19

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Why RCx: Energy Cost

• Lawrence Berkeley National Lab (‘04): – 5%-15% electricity

reduction

– 1%-23% gas

reduction

– 0.2 to 2.1 years

simple payback

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The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Why RCx: Comfort & Air Quality

• Rocky Mountain Institute: – Offices salaries are 72 times energy costs,

92% of the life-cycle cost of a building

– 1% increase in productivity (production rate, quality, or absenteeism) can provide savings to a facility exceeding its entire energy bill

• Lawrence Berkeley National Lab: – $23-56 bn. health care savings potential

– $20-160 bn. in worker performance 21

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Why: Asset Value

• Energy reporting: – Cities (eg Washington DC, Philadelphia, NYC,

Boston) and states (California, Washington) now requiring energy reporting

• Lower operating costs translates to: – Higher lease/occupancy rates

– Higher asset value

22

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Retro-Commissioning Process

• Planning

• Investigation

• Implementation

• Hand-off

23

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Process: Planning Phase

• Select a building

• Define objectives – Testing & tuning system operation

– Energy investments

– O&M strategies

– Procurement

– Training & documentation

– Air quality—noise, CO2, mold/moisture 24

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Process: Planning Phase

• Select a commissioning provider – Referrals, bid posts, trade organization

websites

– History of RCx, energy

– Match expertise to goals

– RFP/RFQ must define minimum qualifications and requirements as well as building information.

25

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Process: Planning Phase

• Building walkthrough – Review by CxA and Owner

– Determine areas of focus

• Develop RCx plan – Building information

– Roles and responsibilities

– Systems to be tested

– Deliverables

– Project timeline and hand-off 26

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Process: Investigation Phase

• Kick-off Meeting – Owner, facility staff, CxA, contractors

– Establish roles

• Review documentation – Drawings, as-builts, O&Ms, submittals,

utility bills, interval data, PM plan, operating requirements (temp, humidity, ventilation)

27

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Process: Investigation Phase

• Review current conditions – Energy use, control systems, operating

procedures

– Current issues, future plans

• Test building systems – Functional test forms

– Sequences of operation

– Building trend data, seasonal testing

– Non-ATC systems: Balancing, lighting

• Review technology – Eg Lighting, BAS, CO2 sensors, VFDs

28

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Process: Investigation Phase

• Document findings – Issue, recommendation, contractor

– Energy recommendations

– Provide priority or cost estimates

– Qualitative effects

• Plan for implementation – Review findings with RCx team

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The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Process: Implementation Phase

• Turn-key method – CxA manages implementation

• CxA-assisted – CxA assists, Owner manages contractors

• Owner-led – Owner manages implementation

• In-house expertise, time are largest factors in selection 30

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Process: Implementation Phase

• Implementation plan – Developed by CxA

– Issues to be rectified, acceptance criteria

• Implementation report – Testing of system adjustments

– Final status recorded

31

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Process: Hand-Off

• Persistence strategies – Training avoids:

• Equipment in hand, 24/7 schedules

• Overridden OA damper, temperature setpoint

• Valves closed

– Adjustable points & authority levels

– Ongoing technical support

– Policies and documentation

– Trending and alarming

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The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Process: Hand-Off

• Close-out meeting – Next steps

– Remaining issues

– Provide documentation

• Final report

• Control sequences

• Equipment inventory and as-builts

• O&Ms

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The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Process: Hand-Off

• Final report – Findings & implementation

– Control sequences & documentation

– Future commissioning recommendations

– Further energy/investment opportunities

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The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Process: Next Steps

• Energy performance tracking – Indicator of persistence

– Tool for future building investments, selection

• Re-Cx and continuous commissioning – Recommission approx. every 5 years, varies by:

• Complexity

• Detail of continuous commissioning

• Energy cost and consumption

• Changes to space use, building systems 35

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

36

Process: Sample Issues

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

37

RH of 11.7% while raining.

Uncalibrated RH sensor

can cause improper

economizer control. OA

temperature often used for

equipment enabling.

Code-required

exhaust air damper

not installed.

Exhaust fan

command remains at

minimum because of

unachievable space

pressure setpoint. Space pressure

erroneous due to

improper

placement of

sensor terminals.

Economizer (free

cooling) available,

desirable, but OA

damper remains at

minimum.

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

38

Unit programmed to cool

to the heating setpoint.

Cooling setpoint found to

be dummy point.

General graphical

issues with damper

and energy recovery

wheel display.

False loading at fully-

closed hot water

valve.

Chilled water PID

loop does not allow

effective response;

overheated air

results.

Lack of exhaust flow

disables possibility

of utilizing energy

recovery

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

39

Use occupancy sensor to

relax setpoints when

space is not in use.

CO2 sensor can

optimize fresh air

intake to reduce

energy consumption.

Fan cycling or speed

control can by employed

depending on

circumstances.

Currently on/off.

Optimized

start/stop,

unoccupied pre-

cooling or other

measures can be

used.

Improve

notifications so

faulty conditions

don’t persist.

Optimize control

with variable-speed

wheel control.

Process: Sample Opportunities

Separate actuators

allow optimized

damper control.

Dual-setpoint control

method can lead to

hunting and competition.

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

40

Process: Sample Opportunities

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Making the Most of RCx

• Best payback if buildings have: – Never been commissioning

Likely more opportunities for optimization

– Newer HVAC systems

Longer lifespan to accumulate savings

– DDC control

Allows control improvements at low cost

– High energy intensity

Greater savings for same cost

See Portfolio Manager or benchmarking tools

41

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Making the Most of RCx

• Best payback if buildings have: – Large HVAC systems

Use more energy

– Critical systems

High energy users, can have qualitative benefits

– Large square footage

Economy of scale

– Comfort or air quality issues

Can be a symptom of inadequate controls

Qualitative and productivity benefits

42

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Making the Most of RCx

• Best payback if buildings have: – Utility incentives

Increase the ROI

– Documentation

Assists in determining intent

• CxA can assist in determining best candidates for RCx.

43

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Making the Most of RCx: Incentives

• Delmarva – Up to $.13/GSF or $26,000

– Further incentives for continuous commissioning

• PEPCO – Up to $.11/GSF or $22,000

– Further incentives for continuous commissioning

44

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Making the Most of RCx: Incentives

• SMECO – Efficient equipment incentives

• FirstEnergy – Efficient equipment incentives

• Baltimore Gas & Electric – Up to $15,000

• Terms vary by utility; CxA can help facilitate incentive payments 45

The Stone House Group

Tel 610.868.9600 Fax 610.868.2272

www.stonehousegroup.net

Questions?

46

Dan Brown

PE, CCP, CEM, LEED-AP THE STONE HOUSE GROUP

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