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Achieving High Performance Operation With Energy Alarms
PRESENTERS:
Mike Eardley, Director of CommissioningCannon Design
Christopher Longchamps, Senior Facilities EngineerPartners Healthcare System, Inc
Agenda
• Define a High Performance Building• Demonstrate how Commissioning (Cx) is a critical element• Define new building Cx, Retro-Cx, and Ongoing Cx• Ongoing Cx program at Massachusetts General Hospital• Partners Healthcare System – Strategic Energy Master Plan
High Performance Buildings
Characteristics• Functionality• Energy Efficiency• Indoor Environmental Quality• Comfort• Sustainability
(ability to perform its function
in a long term)
Building Systems Commissioning
• Buildings function as intended • Realize high performance
•Commissioning (Cx) is a comprehensive and systematic process to verify and document that new or renovated facility systems function completely as designed to meet the owner’s requirements
• A type of quality assurance to the systems being commissioned
• Applied to building systems (e.g. HVAC)
•Core element of sustainable buildings, along with energy modeling and measurement & verification
Commissioning Definition
Without Commissioning
• Placement and calibration of Sensors• Simultaneous Heating and Cooling• Incorrect function of air-side Economizer
and other efficiency measures• Operating Schedule is not what is
necessary, or assumed by energy model• Cycling daylighting and other systems
Reference Standards• ASHE Health Facility Commissioning Guidelines ashe.org
• ASHRAE Guideline 0 The Commissioning Process ashrae.org
• Building Commissioning Association Essential Attributes of Building Commissioning bcxa.org
shutoff valve impeded
moisture penetrationblocked daylight sensor
green cooling tower
Why Commissioning?
Purpose of Functional Testing
• Verification of an operational system• Reduces adjustment and tuning during occupancy• Impacts
energy comfort maintenance functionality
Types of Functional Testing
• Building Automation System• False load• Seasonal testing• Trend analysis
Energy Impacts
• Large effort in sustainable and energy efficient design• Will not be realized if design or intended use is:
misunderstood ignored
• Or if building systems are: operating incorrectly not thoroughly tested
Common Problems – Air-side Economizer
• Damper is stuck / broken / non-functional• Control algorithms fighting
heating during economizer mechanical cooling when free
cooling available• Outside sensor calibration or location
• Not often considered in basic scope
• Affects Air infiltration, IAQ, air/water leaks, building systems performance
• Involves many building components, suppliers & subcontractors
• Coordination meetings; sketches or drawings; wall systems, roof, trade penetrations
• Checklist & Inspections
Building Envelope Commissioning
MoisturePenetration
ThermalBridging
Window Water Testing
Building Envelope
Functional Test – Alarms and Safeties• Varying levels of rigor
verify software interactions verify hardware interactions verify actual conditions
e.g. cold, smoke• Pull the plug
simulate actual loss of power
does transfer and restart act as intended?
•Commissioning: Process applied to new construction or major building renovation
•Re-commissioning: Facility has previously been commissioned and is in need of a “tune-up”
•Retro-commissioning: Performed on facilities that have been in service and never commissioned
•Ongoing commissioning: Ongoing program of structured commissioning throughout the lifetime of a building
New and Existing Buildings
•Review of original design
• Targeted functional testing
• Identification of energy measures
• Evaluation of measures
• Energy modeling
• Implementation
• Verification and Persistence
Retro-Commissioning
Trending
• Functional testing before occupancy is a snapshot• Trending shows operation over time• Methods of trending
building automation system portable data loggers
• Analyze trends spreadsheet calculations software tools
Ongoing Commissioning
• Good Cx process with
functional testing• Better
Re-Cx program• Best
Ongoing Cx• Combination of software,
engineering support, action
PHS Strategic Energy Master Plan Objective
In 2008, PHS Utilities and Engineering Department was charged to develop a Strategic Energy Master Plan to Address the Hospital ever-growing demand for energy and the volatile nature of the Energy market and concerns regarding global warming and long term sustainability of resource consumption and its impact on the delivery of critical health care services
PHS Strategic EnergyMaster Plan Goals
25% or Greater Energy
Consumption Reduction-2008
base line
Increase renewable/sustainable
energy sources
Increase Use of Combined Heat
and Power
Develop 10-year capital outlay
plan
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
0
500,000
1,000,000
1,500,000
2,000,000
2,500,000
Total Energy Consumption (Do nothing) MMBTU based on SEMP 2008 study, including Lunder building
Actual Total Energy Consumption MMBTU After SEMP up to 2012 including Lunder building from invoices
Projected Actual Total Energy ConsumptionMMBTU with MGH SEMP Projected savings from 2012 to 2026
Total Projected Energy Consumption MMBTU with Projected savings from SEMP including Lunder building
Notes:
1.Lunder Building came on line on May 2011 but not fully occupied until late fall 2.Based on escalation of 1.5% load growth
MGH Actual Energy Consumption Vs Projection From PHS Strategic Energy Master Plan Study
2008
2009
2010
2011
2012
2013
2014
2015
2016
0
50,000
100,000
150,000
200,000
250,000
300,000
350,000
400,000
450,000
500,000
MGH SEMP Primary Goal, 25% energy reduc-tion from 2008 based line 1,509,875MMbtu
MGH actual energy reduction compare to Primary goal
MGH Projected Energy Reduction Compare to Primary Goal
MM
BTU
MGH SEMP Actual Total Energy Reduction Compared To 2008 PHS SEMP Energy Reduction Goal
SEMP Impact On Utilities Cost Per Sq.Ft.
MGH Com-bined including CNY, Simches
MGH Main Campus
CNY 149, 114, 75
Simches Yawkey Cox$0
$2
$4
$6
$8
$10
$12
$14MGH Cost per Sq. Ft.
FY 2008 ($/sq ft)
FY 2012 ($/sq ft)
$ /
sq f
t
$6.56
$4.97
$6.08
$4.43
$9.02
$6.83
$12.36
$7.67
$5.38
$11.04
$3.90
$6.90
(6,371,307 ft²) (5,071,825 ft²) (945,947 ft²) (353,535 ft²) (446,960 ft²) (119,808 ft²)
SEMP Impact On Utilities Consumption Per Sq.Ft.
MGH Com-bined including CNY, Simches
MGH Main Campus
CNY 149, 114, 75
Simches Yawkey Cox0
100
200
300
400
500
600MGH kBtu per Sq. Ft. FY 2008 (kBtu/sq ft)
FY 2012 (kBtu/sq ft)
kBtu
/sq
. ft
.
LABS 21Benchmark DOE 2.1 Hospi-
talBenchmark
262
217
251
201
376
294
487
252
210
383
142
217
(6,371,307 ft²) (5,071,825 ft²) (945,947 ft²) (353,535 ft²) (446,960 ft²) (119,808 ft²)
ECMS That Have Major Savings On Outpatient, Research and Outpatient/Research/Office Facility
• Building Occupied / Unoccupied schedule setback• Reduce minimum CFM set point• Schedule Room Thermostat with Dead Band• Fume Hoods modification• Lighting retrofits• Chillers Plant optimization• Steam Traps• Steam Condensate Heat recovery• Low temperature Run-Around Heat Recovery• Reset Pump DP set point• Reset AHU Supply and Return Fans S.P. set point
Lesson Learned
• The Energy conservation measures such as Set point or Schedule setback can be unintentional altered by mechanic
• The Energy Alarms system need to be developed to monitor the MEP system for equipment failures and/or operating out of range
• Energy Alarms can be part of an MEP Maintenance Program• A continuous measurement & verification program needs to be
established to ensure the savings are continued
Massachusetts General Hospital
• Researched ongoing Cx products in the market
• Some required installation of new equipment
• All were costly• Concern about level of
detail in the delivered product
• Settled on customized, built up approach
Massachusetts General Hospital
• Reviewed Design• Developed rules based
logic to identify inefficient operation
• Worked with campus controls provider to implement
What Do Energy Alarms Look At?
• VAV Airflow• VAV Heating Coil• VAV Occupancy Hours• HW HX Valve Leaking• AHU Preheat Valve Leaking• AHU CHW Valve Leaking• AHU Simultaneous Heating & Cooling • CHW Low Delta T• CHW Economizer w/ Chiller(s) Running• AHU Should be in Economizer; Excessive CHW Use
• AHU Should Not be in Economizer; Excessive outside air• More than 79 different types of Energy Alarm are monitored
Energy Alarms Alarm Window
Example of an Air Flow Alarm
• Checks box’s damper operation• Very effective in locating broken damper actuators• Trigger: Box air flow is not meeting setpoint
Logic:• |CFM – CFMSpt| > 0.15 x MaxCFMSpt
[Delay = 1 hr]• CFM = Actual CFM• CFMSpt = CFM Setpoint• MaxCFMSpt = Maximum CFM Setpoint of box
What is One Air Flow Alarm Worth?
Schedule:
5:00AM – 6:30PM Mon-Fri
Occ hrs/wk = 67.5 hr
Unocc hrs/wk = 100.5 hr
Occupied:
(Extra CFM) x (hrs of CFM per week /Total hrs in a week)x($6/cfm)
(711 cfm – 145 cfm) x (67.5 hr/168 hr) x $4/cfm yr = $ 909 /yr
Unoccupied:
711 cfm x (100.5 hr/168 hr) x $4/cfm yr = $ 1,701 /yr
Total Estimated Annual Savings= $ 2,610
Example of a Heating Coil Alarm• Checks that the box’s heating valve is closing completely • Trigger: An unexpected temperature difference across the
heating coil
Logic:• HWV% < 1% & |SAT – DAT| > 10 & CFMSpt > 0
[Delay = 2 hr]• HWV% = Hot Water Valve Position [0%=Closed,
100%=Open]• SAT = Supply Air Temp [Supply Air from AHU to the Box]• DAT = Discharge Air Temp• CFMSpt = CFM Setpoint
What is One Heating Coil Alarm Worth?
Schedule:
5:00AM-6:30PM Mon-Fri
Occ hrs / yr = 3534 hr
Air Side
(325 cfm – 216 cfm) x (3,534 hr / 8,760 hr)
= 44 cfm/yr
44 cfm/yr x $4 /cfm = $264/yr
Total Estimated Annual Savings = $176
How Does An Occupancy Alarm Work?
• Checks if box switches to unoccupied mode• Trigger: Box remaining in occupied mode for a
long period of time
Logic:• Occ > 20 hrs in a 24 hr Period
[Delay = 15 min]• Occ = Number of hours since midnight that the
box has been occupied
Example Of An Occupancy OverrideYawkey Floor 9 Found Overridden ON
Cancer Center Psychiatric Oncology Area
Normal Occupancy Schedule:
5:00AM-6:30PM Mon-Fri
Unoccupied hrs/week: 100.5 hr/wk
Total Minimum CFM: 8,063 CFM
Assuming $ 4/CFM yr
8,063 cfm x (100.5hr/168hr) x $4 /cfm year
Annual Savings: $ 19,294
How Does The Process Work?
• Alarms are reviewed on a daily basis• Once validated there is a work order issued for the repair• Work directly with maintenance staff on difficult problems• Work order completed and issue closed
How Many Energy Alarms Are There?
More than 400 validated work orders have been addressed since summer of 2010 and $600,000 were realized.
Questions / Discussion
Achieving High Performance Operation With Energy Alarms
PRESENTERS:
Christopher Longchamps, Partners Healthcare [email protected]
Mike Eardley, Cannon Design [email protected]
@MikeEardley