Achieving High Performance Operation With Energy Alarms

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 Systemclongchamps@partners.org

Mike Eardley, Cannon Design meardley@cannondesign.com

@MikeEardley