New Approaches to Slash Building Energy & Improve Indoor Environmental Quality

Richardsville Elementary: 1st net-zero school

Richardsville Elementary: 1st net-zero school Bank of America

Largest LEED Plat.

ASHRAE HQ, Atlanta

Gordon P. Sharp, AircuityMGM Macau Casino

Grand Mosque, Mecca

Presentation Overview For Building Energy Savings

Overview & introduction – net zero facilitiesDemand Control Ventilation (DCV)Research on DCV effectiveness and problems “Healthy” DCV

Multiplexed Sensing: A better sensing approachDCV & DOAS DCV case studiesDemand Based Control (DBC) for laboratoriesLaboratory energy analysis & case studies

Goal: Dramatically Reduce Building Energy Use

Outside air: Largest energy & IEQ driver Reducing OA reduces many energy uses

New technologies can help: “Healthy DCV” via Multiplexed Sensing Demand Based Control of lab ACH rates

New codes/standards are supportive New versions of ASHRAE, NFPA 45, others

Result: Dramatic cut in energy use Better IAQ & lower building energy use Labs can often run as low as 2 ACH

If these approaches are used even a Net Zero lab is possible, although many would call that

not just mission difficult but: Mission Impossible!

Applications for Classroom, Offices, & Other Spaces

Optimize Building Ventilation Control

Room/Zone LevelAirflow Control

Building/AHU LevelOutside Air Control

Conventional DCV & Healthy DCV

What about Demand Control Ventilation?

Measures the rise of CO2 in the buildingMeasures amount of ventilationCO2 is a good proxy for human pollutants

Reduces ventilation when occupancy dropsCan save substantial energy when loading variesEven optimizes the ventilation for constant loading

– Most buildings are designed with more air than normally needed

Is DCV a good approach then for saving energy while also improving and validating IEQ?

LBNL* CO2 Field Sensor Study Paper Results10% Dead

81% Read High(avg. 39%!)

9% Low(½ by 50%)

No trends observed with 44 sensors vs site, mfg, or age!

* Lawrence Berkeley National Laboratory: Operated by the University of California for the U.S. Department of Energy

Typical DCV Performance Based on LBNL

-100%

-50%

0%

50%

100%

150%

200%

250%

300%

350%

400%

>20% OA Error ≤20% OA Error Average Over-Ventilaton

Outside Air CFM Error % of Required

64%

27%7%

Average Over-Ventilation

CO2 Sensor Study Results - Iowa Energy Center

15 Models – 13 Manufacturers2 models - 2/3 units met factory spec4 models - 1/3 units met factory spec9 Models - 0/3 units met factory spec

New LBNL CO2 Study of 165 sensors in 25 bldgs

Summary of report: “Together, the findings from the laboratory studies of the Iowa Energy

Center and current field studies indicate that many CO2 based demand controlled ventilation systems will fail to meet the design goals of saving energy while assuring that ventilation rates meet code requirements.”

“The Iowa Energy Center …recently released the results from a laboratory-based study of the accuracy of 15 models of new single-location CO2 sensors. ….Many of the new CO2 sensors had errors greater than 75 ppm, and errors greater than 200 ppm were not unusual. Maximum errors of new sensors approached 500 ppm.”

Forty seven percent of sensors had errors greater than 75 ppm at a concentration of 760 ppm and 40% of sensors had errors greater than 75 ppm at a concentration of 1010 ppm. A significant fraction of sensors have much larger errors, e.g., > 300 ppm. ..Thus, overall many CO2 sensors do not meet accuracy requirements.”

Indian ASHRAE Research plans to replicate LBNL study to validate results here in India with CO2 sensors

And Conventional DCV Concept is Also Flawed

DCV only solves half of the problem DCV varies O.A. based only on number of people in bldg

DCV does not react to non-human pollutants Odors, particles, CO, and formaldehyde

As a result: DCV can create complaints Nonhuman pollutants can rise when DCV reduces O.A.

– New bldg, recent renovation, cleaning materials, vacuuming

Typical response: Disable DCV & increase O.A. RESULT: Increased Energy Costs

Solution: Multi-parameter DCV or “Healthy” DCV

The goal is dilution of all pollutants in building:Human based pollutants (odors, virus, bacteria, etc.)Non human pollutants (TVOC’s, particles, CO, etc.)

Control O.A. based on multiple parameters:Use CO2 as a proxy for human based pollutants EPA & LEED specify levels for non-human pollutants

– TVOC’s, particles, & carbon monoxide

Sensing humidity also helpful to prevent mold

Vary outside air rates based on actual air cleanliness!

Break room 101  Large office 102  Conference 103 

Supply Air Duct

Return/ Exhaust Duct

To BMS

Advisor Data Center

Outdoor Air

Air Data Router

Connectivity

Information Management

Server

Vacuum Pump

Room Sampling Port (RS)Duct Probe

Web User Interface

Sensor Suite with

TVOC, CO2, Dewpoint & Particulate

sensors

Multiplexed Sensing Operation

Sensed Parameters

Air CleanlinessTotal Volatile Organic Compounds

– Photo-Ionization Detector – Metal Oxide Sensor

Particles– Laser based particle counter

Carbon Monoxide (CO) Comfort & VentilationTemperature Humidity or DewpointCarbon Dioxide (CO2)

New LBNL Report also Tested Multiplexed Sensing

Summary of LBNL tests on Multiplexed Sensing “The study results illustrate the advantage of

incorporating a measurement of outdoor air CO2 concentration with each sensor – offset errors cancel out in the indoor minus outdoor CO2 concentration difference.”

Benefits of Multiplexed Sensing ConceptBetter total first cost Single high quality sensor cost for up to 20 locations Single point digital integration w/ building controls

Lower operating costs: Drastically reduced calibration cost

– One high quality sensor to calibrate vs. 20 sensors

Rental approach to sensors – No local maintenance !– Sensors are more accessible, can be swapped out for calibration– No replacement sensor costs during system life

Continuous M&V process for long term energy savings Web based data analysis facilitates real time commissioning

– System degradation can be easily observed and corrected

Cost effective, accurate bldg data for ventilation control

Real Time Intelligent Agent Building Analysis: 

Maintaining the Savings

Goal: Save Energy by Turning Data into Information

What are Intelligent Agent Systems? Typically involves streaming building data to a website  Intelligent agent software analyzes the data in real time

What can these systems do? Identify system anomalies and report back to operatorsAnalyze and help optimize system performance

How do these systems report issues? Summary Reports: Snapshot of system performanceDashboards – Graphically analyze ventilation, IEQ, etc. 

Am I Saving Energy / Money?

Air flow rates are above normal?   WHY?

Could it be a Thermal Issue?

Excess thermal demandApparatus placed near sensor

Ongoing Commissioning: Ventilation Issues

Most spaces are showing overventilated

HEPA FILTERSupply Air

Ongoing Commissioning – Why Overventilated?

What has changed?One or more spaces over/under ventilated

Thermal conditions have changedVentilation Mass balance has deviated from the norm– Does occupant density represent design?– Are occupants gathering where expected?

Another App: Comfort Zone Conformance Analysis

Evaluates Dry‐bulb Temperature & Relative Humidity

Scatter plots give a good idea of T and RH performance

Is Everything Operating in a Healthy Manner?

Detect IEQ events with analyzed data

IEQ Example: Monitor Fan Filter Integrity  

Smart Notification triggers on abnormal particle levelsLevels on discharge of fan filters in two zones stand out

Suggests 1 filter has ruptured, & a 2nd is partially rupturedTechnicians can be deployed to minimize IEQ event

3rd Floor

Dedicated Outside Air Systems (DOAS)

DCV used to control OA to higher occupancy spacesThermal and cooling load decoupled Geothermal Heat Pumps Variable Refrigerant Volume (VRV) Systems Variable Refrigerant Flow (VRF) Systems

Numerous VRV / VRF Manufacturers

DOAS Application Using DCV (K-12)

DOAS provides ventilation requirementFixed OA – wastes energy & requires larger DOASControl OA via CO2 (DCV) – supports energy savings

AND can now take Diversity and Downsize DOAS Over 30 US schools have downsized DOAS by 67%!

– “When CMTA dissected the data further, it discovered that the outdoor air system was consuming half of the HVAC energy. The data led to changes in the outdoor air system to a variable flow, demand control ventilation system on the next WCPS project. “

-- ASHRAE High Performing Buildings Magazine – Fall 2009

Case Study – LEED & Office DCV ProjectsOne Bryant Park

World’s largest, most green skyscraper– Also known as Bank of America Tower

– 2nd tallest building in NYC – 1,250'

– $1.0 B, 2.1M sq. ft. building

LEED Platinum– Aircuity contributed points for CO2, IEQ

Cost effective IEQ monitoring & DCV – Total of over 800 locations monitored

Case Study – LEED & DCV Projects

ASHRAE Headquarters Renewal – LEED CI Platinum Humidity monitoring, DCV control

Sensing for AHU & Enthalpy wheel control

Helping ASHRAE realize its living laboratory goal

TVOC, particles, CO2, Dewpoint , T sensing throughout

Multi-parameter DCV Case Study: Arena

New Jersey Devils – Prudential Arena, Newark, NJ 100,000 sq. ft. sports arena; $310M budgetMulti-parameter DCV control: CO2, CO, particles, & TVOC’s Dewpoint sensing & control for “Best Ice in the NHL”

CO2 ~ 3 days

Concert

NHL Hockey

Indoor Soccer

College/University Case StudiesAcadia UniversityArizona State Univ.Boston UniversityCal State UniversityCarnegie Mellon Univ.Case Western ReserveCentral CollegeColorado Sch. of MinesConcordia Univ.Dalhousie UniversityDartmouth CollegeDavenport UniversityFerris State University Grand Valley State Un.Harvard Law SchoolHarvard (HSPH & Law)Hastings CollegeKansas Univ.Michigan State Univ.

Montana State U.Midwestern Univ.MIST (Masdar Int.)MITNortheastern Univ.Ohio State Univ.Ohio Dominican U.Purdue UniversitySanta Monica Col.Univ. of Ca. IrvineUniv. of Las VegasUniv. of LouisvilleUniv. of MissouriUniv. of MontanaUniv. of N. TexasUCONNUPENNUniv. of WyomingYale University

MIT Sloan School Bldg

Yale Arts & Architecture

UPenn:“Demand Control of airflow is our #1 efficiency approach”

Other Commercial Building Case StudiesBank of America NC HQ.Boeing Corp.ASHRAE HeadquartersBristol Myers SquibbCrocker MuseumDial CorporationDurst, Bank of AmericaESPN – Disney Corp. Eli Lilly CorporationHarrah’s CasinoMohegan Sun CasinoMuscogee Creek CasinoNew Jersey Devils ArenaPNC – Pittsburgh, PAToronto Film FestivalUBS Financial USGBC HeadquartersVornado, 1 Penn PlazaVM Ware Data CenterXcel EnergyArmed Forces Reserve Ctr

Brigham & Women’s Hospital

Prudential Center, NJ Devils Arena

Ariz. State ArchivesBellevue Transit FacilityJ.W. Peck Federal Bldg

Joint Forces Nat’l GuardJuneau Maintenance Bldg King County Metro Base

Kodiak City Police StationLas Vegas City Mob Mus.Mecklenburg CourthouseMcCoy Federal Building

Nixon Presidential LibraryRockingham Judicial Ctr

Brigham & Women’s HospKaiser Permanente

Mount Nittany HospitalMunson Medical CenterNevada Cancer Institute

North Shore Hospital NYU Medical Center

Sloan Kettering Cancer St. Francis Care Hospital Nixon Pres. Library

Research Laboratory Energy Consumption

Lab Energy Usage:5 to 10 times office usage

For many universities:2.5 to 10% sq. footage10 to 40% site energy usage

>65 % of lab energy: HVAC

Achieving Down to 2 ACH Safely in Labs

Goal: Achieve 2 ACH day/night or 3-4 day /2 nightWhat are the drivers of lab airflow that affect this? Hood flows, thermal loads & ACH rates

Hoods Thermal Load

Demand Based Control of ACH

VAV Hoods

ACH / Dilution Requirement

VAV Supply

2 ACH Min

To achieve lab flows down to 2 ACH to reduce energy & 1st

cost, all flow requirements need to be reduced

Min Flow

Min Load

Reducing/Varying the ACH Rate Flow

Demand Based Control (DBC) solution Reduces lab airflow when lab air is “clean” Increases lab flow when pollutants sensed

Studies show lab air clean > 98% time Equal or better safety w/ the Best airflow A fixed min ACH flow is always to high or low When needed flow can be upped to 8-16 ACH

Clean flow setting of 4/2 ACH is typical 4/2 ACH best done as day/night vs. occ/unocc

– Using 3/2 ACH better & more cost effective– Clean flow of 2 ACH (even during day) is best

Demand Based Control (DBC) provides a safe means to achieve 2 ACH

Demand Based Control

ACH Requirement

2 ACH Min

ASHRAE Handbook Provides New Guidance

New 2011 ASHRAE Handbook, Lab chapter 16:Active/Demand Based Control is recommended:

– “Reducing ventilation requirements in laboratories and vivariums based on real time sensing of contaminants in the room environment offers opportunities for energy conservation.”

– “This approach can potentially reduce lab air change rates down safely to as low as 2 air changes per hour when the lab air is ‘clean’...”

New Delhi, India Example Analysis Assumptions

Model typical bldg. w/ 12.5K GSMLab & lab support area: 5.0K NSMOffice area: 3.0K NSM

Base dilution ventilation:Conservative 6 ACH baseline

Energy Cost, assumes true costElectric: $0.12/kWh Avg (6.4 INR/kWh)Heating: $1.00/therm (1.8 INR/kWh)

Low Fume Hood density:One 6’ FH/ 667 ft.2 module (75)

Manifolded exhaust fans: 4 fans are staged plus 1 spare

6 ACH Baseline Energy Costs For New Delhi

Cooling dominates energy use: 54% of totalSkin & solar gains typically small compared to OA

Total baseline energy use is 300 Lakh/ year

New Delhi DBC Energy Savings of 4 Day/2 Night ACH

Demand Based Control reduces lab HVAC energy by 146 Lakh or by 49% vs. 6 ACH. Payback is 2.0 years.

Lab Case Study: Arizona State UniversityASU Biodesign Institute Bldgs A & B Retrofit Retrofit of Labs and Vivarium

LEED® NC Platinum, R&D 2006 Lab of the Year (Bldg. B) Lab DCV pilot in 2007 to look for EE: 65% savings achieved Full building (A&B) retrofitted in 2009: $1 Million saved/year Currently 24 buildings have been retrofitted:

– Office, classroom, library, sciences bldgs, sports arena & others

0 CFM

2,000 CFM

4,000 CFM

6,000 CFM

8,000 CFM

10,000 CFM

12,000 CFM

14,000 CFM

16,000 CFM

18,000 CFM

May-17 May-24 May-31 Jun-8 Jun-15 Jun-22 Jun-29 Jul-6 Jul-16 Jul-23 Jul-30 Aug-6 Aug-13 Aug-20 Aug-27 Sep-3 Sep-11

Exhaust CFM Supply CFM

Average Savings: 10,757 CFMIn 11 Zones (~8,000 ft2)

At $5.14/CFM annually= $55,290 annually= $6.91/ft2 annually< 11 month payback!

Old Average Supply: 15,978 CFM

New Average Supply air : 5,221 CFM

June 4, 2007System

Activation

10,7

57 C

FM S

avin

gs

Pilot Study Results

Major Energy & Capital Impact for Near Zero Labs

Masdar City, Abu Dhabi - Largest net/near zero project Near zero emissions lab w/ Demand Control & chilled beams

– 150K m2 total, ~ 40K m2 of labs: MIST 1 A (Built) & 1B (Under const.)

Projected total energy savings: $2 M $ or 9,000 MWh /year – Labs operate at 2 ACH (day & night), purge up to 14 ACH

Downsized mechanical system to save HVAC capital costs Cuts solar PV capacity by ~ 3.75 MW or ~$20M first cost!

MIST 1A: 50K sq. m., 15K sq. m labs

First Cost Saving at Univ. of Houston

Health & Biomedical Sciences Center / Optometry 6 Floors, ~150K sq. ft, 71 labs, 37 vivariums & 24 non-lab zones

Lab & Vivarium flows reduced: Labs from 12 ACH to 4 ACH Vivariums from 15 ACH to 9 ACH

DBC Installed cost : ~ $500KEst. energy savings ~ $250K/ yr2.0 year payback: energy onlyFirst cost savings up to $1.0M!

DBC was a critical add to help bring project into budget

Laboratory/Vivarium Case StudiesAcadia UniversityAlbion College Arizona State UniversityBeth Israel Medical CenterBristol Myers SquibbChicago Botanic Garden Cal State Univ., Monterey Cal TechCase Western Reserve Univ.Colorado Sch. Of MinesChildren’s Hospital of Phil.Dalhousie Univ.Dartmouth CollegeEli LillyFerris State UniversityFood & Drug Admin. (FDA)Ferris State UniversityGrand Valley State UnivHarvard (HSPH)Indiana/Purdue Fort Wayne

Hastings CollegeLabCorp – BioRepositoryMasdar Institute, UAEMichigan State UniversityMidwestern UniversityMinistère de l’agriculture, Montreal Heart instituteNational Inst. of Health (NIH)Nevada Cancer InstituteOhio State UniversityOklahoma State UniversityRice UniversitySabanci University, TurkeyTexas Children’s HospitalUniversity of Cal IrvineUniversity of IowaUniversity of LouisvilleUniversity of Pennsylvania Univ. Health Network: MaRSVan Andel Institute

Univ. of Louisville: Bio Med 3

UPENN:Carolyn Lynch Lab

UPenn: FisherOver 200 lab building projects using DBC

DCV & Multiplexed Sensing Summary

DCV done correctly can increased savings & IEQ: Use multiplexed sensing to solve sensor accuracy issues Sensor “rental’ approach to solve maintenance concerns

DBC: Single greatest means to cut lab energyApplicable to new & existing building types Office buildings Classroom & Educational Lab & Vivarium Healthcare Public Assembly & Arenas

Questions?For a copy of the presentation, contact:

Gordon Sharp, gsharp@Aircuity.com