Cutting Hospital Energy Use in Half Blueprint

AEDG Large Hospitals: A Blueprint for Cutting
Your Hospital Building Energy Use in Half
Terry E. Townsend, P.E., FASHRAE, LEED®AP, ASHRAE Presidential Member
June 26, 2013

AEDG Large Hospitals: A Blueprint for Cutting
Your Hospital Building Energy Use in Half
“I do solemnly vow….that above all else I will serve the highest
interest of my patients through the practice of my science and
art…” HIPPOCRATIC OATH
“I swear …to provide adequately for people’s needs; to preserve
and help regenerate the environment, both natural and built…”
THE ARCHITECT’S OATH
“I pledge to…serve humanity by making the best use of Earth’s
wealth; my skill and knowledge shall be given without reservation
for the public good…
THE ORDER OF THE ENGINEER
The Mission of Healthcare Facilities = provide an environment of
care for healing patients

Why Should Owners, Architects and Engineers
be Concerned?
Two Types of Energy Targets
* Energy Use Index/Intensity (EUI) – includes no on-site
renewable energy generation
EUI = Total Annual Energy Use (kBtu/SF-yr)
Gross Floor Area
* Net Energy Use Intensity (NEUI) – includes photovoltaic
and other on-site renewable energy production
NEUI = Net Annual Energy Use (kBtu/SF-yr)
Gross Floor Area

Table 1. BASE Energy Use Intensities based upon ANSI/ASHRAE/IESNA Standard 90.1-2004 by Subsector and Climate Zone, in
kBtu/ft2-yr
Subsector
Climate Zone
All 1A 2A 2B 3A 3B 3C 4A 4B 4C 5A 5B 6A 6B 7 8
All 71 82 68 73 78 58 62 70 55 56 75 64 76 74 74 74
Office/professional 57 55 61 65 52 46 44 60 58 53 60 48 62 61 68 68
Nonrefrigerated warehouse 41 27 31 31 37 30 30 42 49 30 47 51 50 47 45 45
Education 52 52 49 57 42 41 54 60 34 43 53 44 60 64 64 64
Retail (excluding mall) 68 68 66 66 63 54 54 68 58 58 73 71 76 91 100 100
Public assembly 62 66 66 66 72 52 52 54 48 77 68 50 66 51 70 70
Service 83 83 78 78 60 63 63 79 52 52 92 76 102 86 108 108
Religious worship 44 40 40 40 29 29 29 44 59 59 51 35 57 39 44 44
Lodging 55 65 51 51 52 40 40 57 61 61 55 51 60 64 63 63
Food Services 354 354 354 354 380 375 375 368 368 368 336 283 341 341 354 354
Health care (inpatient) 111 108 108 108 118 98 97 106 106 106 115 106 113 116 116 116
Public order and safety 67 54 54 54 67 67 67 60 60 60 78 78 73 87 87 87
Food sales 181 200 200 200 190 151 151 188 188 188 173 182 208 208 181 181
Health care (outpatient) 76 76 80 80 64 79 79 66 66 66 90 76 82 78 107 107
Vacant 30 30 23 23 30 20 20 41 41 41 21 21 40 40 40 40
Other 58 73 73 73 58 58 58 57 57 57 61 61 63 63 63 63
Skilled nursing 131 132 132 132 113 102 103 145 145 145 142 106 132 132 132 132
Laboratory 323 323 323 323 323 369 369 272 272 272 313 313 323 323 323 323
Refrigerated warehouse 86 86 86 86 86 86 86 88 86 86 85 86 86 86 86 86

Large Hospital Energy Use Targets to Achieve
50% Energy Savings
Plug/Process Lighting HVAC
Climate Zone Loads Loads Loads TOTAL
(kBTU/SF-yr)
3A 38 18 62 118
4A 38 18 65 121

Advanced Energy Design Guidance

• Present a way, but not the only way to build energy
efficient buildings that use significantly less energy
than those built to the minimum code requirements
• Energy Savings targets when compared to
ANSI/ASHRAE/IESNA Std 90.1-1999 (30%); 90.1-
2004(50%) progress towards NZEB
• More advanced savings (70+% NZEB) documents
to be covered later.

Advanced Energy Design Guidance for
Large Hospitals – Executive Summary
• Building Envelope 45% better than 90.1-2004
• Whole Building LPDs 25% better than 90.1 -2004
• Diagnostic & Treatment LED Lighting that saves 60%
• Exterior Lighting recommendations save 33%
• ENERGY STAR exclusive plug-in equipment; best-in-
class commercial kitchen equipment; traction
elevators + ‘regenerative’ traction elevators for
high-use
• Service Water Heating 13% better than 90.1-2004

Advanced Energy Design Guidance for
Large Hospitals – Executive Summary
• Aggressive reduction in reheat by decoupling space
conditioning loads & ventilation loads with DOAS
and zone level conditioning equipment or advanced
VAV w/separate OA treatment, heat recovery chiller,
aggressive supply air temperature re-set, and zone
airflow setback
• Airflow setback in surgery suites, high equipment
efficiencies, air-side energy recovery, air side
pressure drop & coil face velocity reductions,
elimination of steam boilers & high ΔT chiller loops

BACKGROUND INFORMATION
• Primary Focus = New Hospitals; Recommendations
are also applicable to renovation projects (partial or
complete), remodeling and modernization projects
• Basis of AEDG = 427,000 SF Regional Hospital
• Energy Savings –
ASHRAE Standard 90.1-1999 = 56% - 64%
ASHRAE Standard 90.1-2004 = 50% - 59%
ASHRAE Standard 90.1-2007 = 49% - 58%
ASHRAE Standard 90.1-2010 = 34% - 45%

HOW TO ACHIEVE 50% ENERGY SAVINGS
“GAME PLAN”
• Obtain Building Owner Buy-in
• Assemble an Experienced, Innovative Design Team
• Adopt an Integrated Design Process
• Hire a Daylighting Consultant
• Utilize Energy Modeling during Design Phase
• Use Building Commissioning Authority (CxA)
• Train Building Users and Operations Staff
• Monitor the Building Performance/On-going
Commissioning (OCx)

Conditions to Promote Health and Comfort
“GAME PLAN”
• ASHRAE Guideline 10 Interactions Affecting the
Achievement of Acceptable Indoor Environments
• Ventilation & IAQ – ASHRAE Standard 62.1-2010,
ASHRAE Standard 170-2008 Ventilation of Health
Care Facilities & ASHRAE IAQ Guide: Best Practices
for Design, Construction & Commissioning
• Thermal Comfort – ASHRAE Standard 55-2010,
ASHRAE Standard 170-2008

Conditions to Promote Health and Comfort
“GAME PLAN”
• Visual Comfort – IES The Lighting Handbook, 2012
• Acoustic Comfort – AIA Guidelines for the Design and
Construction of Healthcare Facilities, 2010
- 2009 ASHRAE Fundamentals
Handbook, Chapter 8, “Sound and Vibration”

Project Delivery Methods Comparisons
Traditional Projects Integrated Projects
• Fragmented TEAMS Key Project Stakeholders
• Linear/Segregated PROCESS Concurrent/Multilevel
• Individually Mang’d RISK Collectively Managed
• Individually Pursued COMPENSATION Team Value-based
• Paper based COMMUNICATIONS/ Digitally Based/
TECHNOLOGY Virtual/BIM
• Unilateral Effort AGREEMENTS Multilateral Collaboration

Integrated Design Project’s Phases
Design Phase
• Pre-Design (Project Kickoff, Programming & Concept Design)
• Initiation of Commissioning Activities (CxA)
• Schematic Design & Design Development
• Construction Documents & Bid Process
Construction Phase
• Design Team & CxA Activities
Post Occupancy Phase
• Design Team Close-out & CxA M&V Activities
• Development of an On-going/Performance Cx Program

High Performance Integrated Design
Overview of Design Influences
“A Large Hospital’s Primary Inpatient Units (IPUs) or
Wards and Diagnostic and Treatment (D&T) Spaces
are usually exceeding high energy users due to
constant operation of HVAC and lighting systems.”
STEP 1 – Assess relationship between ventilation loads
and annual/peak heating/cooling loadsdecouple &
decentralize systems. Realized Results include:
• Heating is the dominant load in every climate & can
be eliminated with aggressive heat recovery,
• Fan energy is greatly reduced with decoupling and
the distributing Htg/Clg w/water-based systems

Overview of Design Influences
• Cooling Loads greatly reduced but still significant.
STEP 2 – Attend to building massing and envelope
designprioritizing daylighting zones (impact of
daylighting on medical outcomes, patient wellbeing
& caregiver performance is well documented.
• Aggressive reduction in circuited lighting power,
• Aggressive lighting controls,
• IPU has most aggressive daylighting goals.
STEP 3 – Reduce electrical energy consumption
associated with lighting, plug and process loads.

Energy Conservation Measures (ECMs)
Major ECMs pertain to Envelope, Lighting, HVAC and
Controls
Envelope
• Enhanced insulation for walls and roofs
• Thermal mass in opaque envelope for energy storage
• Cool Roof (most climates)
• Exterior shading on east, west and south-facing windows
• Limited use of flay-roof skylights (N-facing celestories)
• Vestibules at openings to outdoors
• Continuous air barrier (infiltration, condensation & press.)

Controls
Lighting
• Fenestration responsive to site-specific solar exposure,
• High-performance glazing – meet lighting design, block
solar radiation & minimize transmission gains/losses,
• Effective shading devices during peak cooling times,
• Electric lights automatically dimmed or turned off through
use of daylight-responsive photo-sensors

Controls
HVAC & Controls
1. Water-source heat pumps (WSHP) with DOAS
2. Mixed-air VAV with separate OA treatment
3. Fan Coil with DOAS
• Aggressively Address Reheat
+ Air-side recovery devices
+ System Type Selection (CAV not an option)
+ Supply air temperature reset

Controls
HVAC & Controls
• Aggressively Address Reheat
+ Supply air temperature reset – when bldg is not at peak
cooling load & outdoor dewpoint is below 54 °F
+ Plug Loads/Passive Reheat
• Supply Low Dew Point at High Air Temperature
• Low Occupancy Mode – Ventilation reset by Occupancy
sensors; Time-of-Day sensors; CO2 sensors
• Simplify HVAC Systems

Controls
Central Plant Systems
• Wring as many BTUs out of distributed fluid (increase ΔT
and reduce flow rates)
• Make distribution pipes and ductwork as large as practical
• Consider each utility as a system
• Design system for specific requirements of a particular
building
• Recover and reuse energy whenever possible

Controls
Control Strategies
• Shared information technology backbone & routing for
web-based access
• Shared connections of sensors between HVAC & lighting
• Motorized blind control algorithms
• Facilities’ scheduling software interlinked with HVAC
• Energy-use dashboards showing instantaneous energy use
or monthly energy use by department
• Overlays of Systems’ energy-use intensities by use

BIM, BAS and CMMS (Example)
The potential for the integration of Building Information
Modeling (BIM), Building Automation System (BAS) and a
Computer Maintenance Management System (CMMS) is
best demonstrated –
• BAS High-Temp Alarm in VAV Box; valve cycled;failed
• BAS opens ‘Corrective Maintenance Ticket’ in CMMS
• CMMS/BAS establish priority based on occupancy type
• CMMS queries BIM database for maintenance activity;
dispatches Work Order with required information
• Technician has exact location, required tools & material for
repairs w/o occupant knowledge of ‘a problem’

Building Systems Commissioning (CxA)
• Process Cx utilizes a paper-based process that is
usually conducted by the project’s contractors/sub-
contractors (First Party Validation)
• Technical Cx utilizes a technical testing-based
approach that is conducted by the CxA (Third Party
Validation) and includes system adjustments and
optimizations

Design Phase CxA Deliverables
a. Updated Owner’s Project Requirements (OPR)
b. Issues Log
c. Commissioning Plan
d. Updates to the Basis of Design (BOD)
documentation
e. Commissioning Specifications

Construction Phase CxA Deliverables
a. Site Observation Inspections & reports
b. Pre-Functional Tests (PFTs)
c. Functional Performance Tests (FPTs)
d. Issues Log & Deficiency Resolutions
e. Owner Training in O&M and functions of building’s
systems
f. Systems’ Manual
g. Final Technical Cx Report

Construction Phase CxA Deliverables
a. Deferred Tests (PFTs and FPTs)
b. Performance Verification Testing (PVT)
c. Updated Final Technical Cx Report with Deferred
Tests and PVTs
d. Development of an On-going/Operations Technical
Cx Plan and Program for Facility O&M Staff.

Prescriptive Recommendations
• Envelope
– Roof
– Walls
– Floors
– Slabs
– Doors
– Vestibules
– Continuous Air Barriers
– Vertical Fenestration
– Interior Finishes
– Form-driven daylighting
– Non-form driven day-
lighting
• Interior Lighting – Multiple
Options
• Exterior Lighting
• HVAC
– WSHP w/DOAS
– Fancoil w/DOAS
– VAV w/DOAS & heat
recovery system
– Heating Systems
– Humidification Systems

Prescriptive Recommendations
• Equipment Choices
- Computers
- ENERGY STAR Equipment
- Vending Machines
• Controls/Programs
- Power/outlet controls
- Occupancy Sensors
- Timer Switches
• Process Loads
- Elevators
• Service Water Heating
• Kitchen Equipment
- Cooking equipment
- Refrigeration equipment
- Exhaust Hoods

Envelope Recommendations
“Roof”
Zone 3 ; Zone 4
• Insulation entirely above deck = R-25 ci ; R-30 ci
• Solar Reflectance Index (SRI) = 78 ; “No Rec”
• “ci” = continuous insulation; “LS” = liner systems
• “No Rec” means the more stringent of either 90.1
or the local code requirements
• “FC“ = Filled Cavity

“Walls”
Zone 3 Zone 4
•R-11.4 ci R-13.3 ci
R-13 + R-7.5 CI
•R-7.5 ci R-7.5 ci
• Mass (HC>7 Btu/ft2F)
• Steel framed
• Below grade walls
• “HC” = Heat Capacity

“Doors”
Zone 3 Zone 4
• U-0.70 U-0.50
• U-0.50 U-0.50
• Swinging
• Nonswinging

“Vertical Fenestration – View Glass”
Zone 3; Zone 4
40% of Net Wall
• Nonmtl = 0.56;0.38/ Mtl =
0.65; 0.44
• Nonmtl = 0.41;0.26/ Mtl =
0.60; 0.38
• PF = 0.5
• Window-to-wall Ratio
(WWR)
• Thermal transmittance
• SHGC
• Exterior sun control
(S only)
• “PF” = Projection Factor

Daylighting Recommendations
“Form-driven”
Zones 3 and 4
• All Spaces – LEED for Healthcare credit (IEQ 8.1)
• D&T Block – Area within 15’ of perimeter exceeds
40% of footplate
• IPU – 75% of occupied space lies within 20’ of
perimeter
• Staff Areas; Public & Other – Maximize access to
natural light (sidelighting & toplighting)
“D&T” = Diagnostic & Treatment
“IPU” = Primary Inpatient Units

Daylighting Recommendations
“Nonform-driven”
Zones 3 and 4
• Staff areas (exam rooms, nurse stations, offices &
corridors) and Public spaces (waiting and reception)
– Daylighting controls to any space within 15’ of a
perimeter window

Interior Lighting
Recommendations
Zone 3; Zone 4
0.9
85
>50
Manual On – Auto/timed-off
- all rooms
Dim all fixtures in daylight
zones
• Lighting Power Density
(LPD) (W/ft2 max)
• Light Source System Efficacy
(mean lumens/watt min)
Linear Fluorescent
All other sources
• Lighting Controls – General
• Dimming Controls –
Daylight harvesting
• “Efficacy” = Lumens/Watt

Exterior Lighting
Recommendations
Zones 3 & 4
• Façade & Landscapping – LPD = 0.15W/SF
• Parking Lots – LPD = 0.1w/SF
• All Other Exterior Lighting – No Rec; Auto reduce to
25% (12 am – 6 am)

HVAC Equipment and Systems
Recommendations for Multiple System Types
Zones 3 & 4
• WSHP w/DOAS
• Fancoil System w/DOAS
• VAV AHU System w/DOAS & Heat Recovery

HVAC Equipment Recommendations
- WSHP System w/DOAS
Zones 3 and 4
Efficiency Cooling Heating
Water Source HP 17.6 EER 5.0 COP
WSHP Compr. Control 2-stage or variable speed
WSHP Circ Pumps VFD or NEMA Premium Efficiency
WSHP Cooling Tower VFD on Fans
Boiler Efficiency 90% EC
WSHP Fans 0.4 W/cfm
DOAS (Humid;Dry;Marine) 60% Total Effectiveness
DOAS Ventilation Control DCV with VFD

-Fancoil w/DOAS
and Chiller/Boiler Systems
Zones 3 & 4
Water-cooled Chiller Efficiency 6.5 COP
Water Circ Pumps VFD and NEMA Premium Efficiency
Cooling Towers VFD on tower fans
Gas Boiler 90% Ec
Max Fan Power 0.4 W/cfm
Fancoil Fans Multiple Speed
Exhaust-air energy recovery DOAS 60% Total Effectiveness
DOAS Control DCV with VFD

- VAV w/DOAS + Heat Recovery
and Chiller/Boiler Systems
Zones 3 & 4
Heat Recovery Water-cooled Chiller 4.55 COP
Water-cooled Chiller Efficiency 6.5 COP
Water Circ Pumps VFD and NEMA Premium Efficiency
Cooling Towers VFD on tower fans
Gas Boiler 90% Ec
Max Fan Power bhp < supply cfm * 0.0012 + A
Economizer No Rec
DOAS Energy Recovery(Humid;Dry;Marine) 60% Total Effectiveness
DOAS Control DCV with VFD

Ventilation and Ductwork
Zones 3 & 4
• Dedicated OA System required on WSHP, FC w/DOAS
& VAV w/DOAS + Energy Recovery systems
• Motorized outside air damper control required
• Energy Recovery required
• Lower duct friction (design them better) (0.08in
WC/100 ft)
• Interior only ductwork (reduce impact of possible
leakage)
• Duct insulation: R-6
• Ductwork sealing Class A

Service Water Heating –
Zones 3 & 4
• Point-of-Use - 0.81 EF or 81% Et
• Heat Pump WH – 2.33 EF
• Pipe d < 1½” – 1 ½ ” insulation
• Pipe d ≥ 1½” – 1½ ” insulation
• “EF” = Energy Factor

“How-to” Guidance - Envelope

Swedish Issaquah Hospital
Seattle WA

Case Study
• Building Information Ancillary Buildings
* 350,000 Sq.Ft. * Medical Office Bldg
* 4-story Acute Care Hospital (200,000 SF)
* 175 Beds * Central Utility Plant
* Emergency Rooms
* Surgery Suites
* Imaging Department
* Labor & Delivery
* Intensive Care Unit
* Cancer Facilities

Case Study
• Integrated Design
* EUI Target = 150 kBTU/SF/yr (comparable area
hospitals have EUIs ranging between 260 – 265
kBTU/SF/yr
* Design Team created a decision matrix that gave
a delivery schedule of components that shaved 1
year off project delivery
- CUP piping & utility tunnel piping + racks and
MOB Mechanical Room prefabricated off-site
- All Terminal Units were procured early

Case Study
• Building Envelope & Daylighting
* Due to energy model development activities, the
baseline envelope was not changed.
• HVAC Systems
* All HVAC & SWH Systems recover and reuse heat
* Core of HVAC System = heat recovery chiller (HRC)
* Heating & SWH Systems supplemented by a
condensing boiler (operates when OA < 40 °F)
* Cooling Air Temp (avg) = 62 °F

Case Study
• Energy Modeling
Energy Savings Analyses
Strategy Ttl Cost Yrly $avings SP (yrs)
Light Occ. Sens $22,941
VAV $973,047 $342,183 3
Heat Rec Sys $1,103,971 $115,081 10
Low Stat P AHU $398,312 $31,742 13
Low Stat P Duct $314,983 $19,538 16
VSD Chiller $208,998 $11,144 19
Over 70 Strategies were studied.

Case Study
• Resulting EUI = 135 kBTU/SF/yr (Target – 150)
• Energy Use Breakdowns –
– Space Heating = 22.7 kBTU/SF/yr
– Space Cooling = 1.6 kBTU/SF/yr
– Lighting = 22.9 kBTU/SF/yr
– Steam Process = 10.3 kBTU/SF/yr
– Ventilation/Fans = 24 kBTU/SF/yr
– Pumps = 6.1 kBTU/SF/yr

Your Role, Your Duty and Your
Responsibility
“Don’t be put off by people who know what is
not possible. Do what needs to be done, and
then check to see if it was impossible only
after you are done.”
Paul Hawken
University of Portland Graduation Address
May 2009

Cutting Hospital Energy Use in Half Blueprint

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