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Welcome to the Western Cooling Efficiency Center’s Year-In-Review for the 2014-2015 year. We are excit-

ed to share with you highlights of our notable research for this past year, encompassing innovation, evalua-

tion, and commercialization of new energy efficiency solutions. The Year-In-Review displays the diversity and

uniqueness of our research and findings. These discoveries promise great benefits for California and beyond.

WCEC is reshaping the landscape of opportunity for energy efficient building systems. We are challenging

long standing precedents, and exploring solutions that promise dramatic savings. This is an exciting time.

Technology is evolving rapidly and we are working closely with our industry affiliates to forge a strategic path

forward. Together, we are developing a broad range of solutions, including new and sometimes unconven-

tional perspectives about the future of thermal energy systems in buildings.

LOOKING TOWARD OUR ENERGY FUTUREOur research successes and innovations are owed largely to the cooperative interests and combined efforts of

our valued network of industry partners, collaborators, and research sponsors. In light of the growing energy

and environmental challenges we face, we know these upcoming years are important. WCEC is proud to be a

part of this movement to reshape the focus and direction for our energy efficient future, and we look forward

to this continued progress.

Welcome

WCEC MISSION: Accelerate development and commercialization of efficient heating, cooling, and energy distribution solutions through stakeholder engagement, innovation, R&D, education and outreach.

EVAPORATIVE COOLING SOLUTIONS STILL MAKE

SENSE FOR WESTERN CLIMATES.

Using only 3% of urban landscape

water would save 4,000 gWh and would remove the greenhouse gas emissions of 600,000 cars.

NEW BUILDING ZERO NET ENERGY IS ONLY PART OF

THE EQUATION.

80% of HVAC manufacturer sales are for existing buildings—technol-

ogy that is appropriate for existing

buildings will drive the availability

of high efficiency products for all

applications.

TECHNOLOGY IS ONLY ONE PART OF THE

SOLUTION.

The way that new technology is ap-

plied, and the ways that we use and

interact with these systems, can

be as important to ultimate energy

savings as the technical innovation

behind a new efficiency measure.

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What is WCEC?The Western Cooling Efficiency Center is an authoritative and objec-

tive research center at UC Davis that accelerates the development and

commercialization of efficient heating, cooling, and energy distribu-

tion solutions.

Our work is increasingly important as energy policies in the US and

California recognize the far-reaching implications of greenhouse gas

emissions on our environment and changing climate.

HOW WE WORK

Applied ResearchWorking closely with manufacturers, policymakers and utilities,

WCEC tests new and existing HVAC technologies in our laboratory.

We also deploy real world demonstrations that provide objective

technology evaluations of field performance. Our engineers recom-

mend and implement performance improvements for the technolo-

gies tested.

Human Factors & Policy ResearchWe understand that even game changing technologies face consid-

erable barriers to adoption that include policy, market and human

interaction. WCEC works with policymakers, supporting codes and

standards that will save energy and promote new, efficient tech-

nologies. We also work closely with our Utility partners, to evaluate

technologies for market incentives, and in parallel, address human

behavioral factors.

WCEC’S NEW ASSOCIATE DIRECTORWCEC welcomes Dr. Vinod Narayanan as the Center’s new

Associate Director. His most recent position was as the

Professor of Engineering at Oregon State University. Dr.

Narayanan specializes in microscale flow and heat transfer

for energy efficient applications, including solar thermal,

solar fuels, thermal management, and phase-change heat

transfer. Dr. Narayanan brings a strong background in

heat and mass transfer research that expands the range

of solutions WCEC can provide to our sponsors.

THE UC DAVIS ADVANTAGEAs part of the University of California Davis, WCEC has

access to a diverse set of resources spanning multiple

disciplines that only a world-class university can pro-

vide. Together, with UC Davis’ College of Engineering

and the Energy Efficiency Center, WCEC is advancing

the HVAC industry, progressing towards California’s en-

ergy goals and reshaping what is truly possible in HVAC

energy efficiency.

est. 1905

Learn more» wcec.ucdavis.edu

Leaders in climate-appropriate cooling technologies

In-house laboratory with environmental chamber capable of re-creating 95% of California’s hot/dry climates

Leaders in automatic aerosol sealing technology for buildings

Building energy modeling

Technology evaluation

Hot/Dry climates

Codes & Standards

Human behavior in HVAC

Thermal energy distribution

HVAC system control

Core Proficiencies

Heat

&Mass Transfer

Extensive Knowledge In:

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Most HVAC systems are designed as a one-stop solution

to heat and cool in any climate region. Though these

units can be efficient, they cannot hope to achieve the

larger efficiency gains available through a more fo-

cused design strategy. Tailoring equipment design to a

specific climate type allows manufacturers the ability to

optimize their technologies to operate more efficiently

in that particular climate. More specifically, in hot and

dry climate zones, the use of evaporative technologies

to cool or pre-cool air can have a significant impact on

energy savings.

The Western Cooling Challenge is a multiple winner

competition that encourages HVAC manufacturers to

develop climate-appropriate rooftop packaged air con-

ditioning equipment that will reduce electrical demand

and energy use in Western climates by at least 40%

compared to current federal standards. WCEC’s ulti-

mate goal with the Challenge is to create a consistent,

reliable benchmark for new climate-appropriate tech-

nologies that will inform building owners, policy makers

and utilities. The Challenge is also a platform to work

with manufacturers to advance the application and ad-

vocate for these climate-appropriate technologies.

The Western Cooling Challenge

RETROFIT CASE STUDY: PALMDALE

15%Cooling energy & CO2 savings

up to

40%Peak cooling demand kW savings

3.5gallons

Water used per kWh saved

http://bit.ly/WCCCSpalmdale

20%

CASE STUDY: ONTARIO

Cooling energy & CO2 savings

up to

66%Peak cooling demand kW savings

5gallons

Water used per kWh saved

http://bit.ly/WCCCSontario

PROJECT REPORT: MUNTERS EPX5000

Using one EPX5000 on a roof with 5 other RTUs showed a 20% reduction in electrical demand for the whole building HVAC.

20%

http://bit.ly/WCCepx5000labThe Multi-Tenant Light Commercial project aims to reduce energy and peak consumption by at least 30%.

TECHNOLOGY PACKAGES EVALUATEDRetrofit kits: Products in this category are characterized as a deep retrofit of an RTU, replacing parts (ie: variable speed fans) and adding

controls to optimize performance.

Advanced Thermostats: These are devices that typically involve a one-for-one replacement of a thermostat but offer expanded func-

tionality over a traditional ON-OFF thermostat. Generally, advanced

thermostats will offer some form of remote monitoring and control,

precise and easily configurable scheduling, and potential for integra-

tion with larger energy management systems and utility demand re-

sponse programs.

Evaporative Cooling: Evaporative condenser air pre-cooling is used to improve the efficiency of existing vapor-compression equipment.

Multi-Tenant Light Commercial

$1,713.

WCEC is working to address the traditionally under-served market of

Multi-Tenant Light Commercial (MTLC) buildings. These buildings are

defined as having 2-25 small tenants in a building owned by a single

landlord. Examples of MTLC buildings are strip malls, office parks and

mixed use properties. Retrofitting these buildings represents a real

challenge for several reasons. Low access to capital, principal-agent

problems (the owner typically does not pay the utility bills), short-

term leases, and a large variety of end-use types are some of the bar-

riers identified for this market.

$291. Energy Savings estimate per year*

$428. Energy Savings estimate per year*

Energy Savings estimate per year*

*Savings estimates based on a medium restaurant with two, 5-ton RTUs 7

WHAT’S NEXT:Commercial Applications: WCEC will begin testing the aerosol technology in commercial buildings this year.

Gas Pipelines: A WCEC laboratory test shows a successful application of the aerosol tech-nology sealing a leak in a 150 ft. gas pipe within 20 minutes. The next step will be to test sealing

efficacy in a longer laboratory application, and later, a field demonstration.

Automating the process of sealing leaks in buildings

Building envelope leaks are a significant factor in energy

consumption, accounting for over 30% of the total

energy used for HVAC. Sealing buildings by means of

aerosolized sealant particles is a promising technology,

providing a cost-effective solution that can dramatically

reduce the total leakage in buildings.

Sealing building envelopes saves energy by eliminating

infiltration of unwanted, unconditioned air, reducing the

loss of conditioned air and reducing the demand for

cooling and heating. Existing envelope sealing practices

require many contractor hours, manually sealing leaks

with no guarantee that the majority of leaks have

been found or sealed. Sealing building envelopes with

aerosol particles eliminates the guess-work—sealing

leaks a person is unlikely to notice—all while providing

instantaneous feedback and verified results.

Aerosolized Sealant for Building Envelopes Aerosol sealed leak at the Honda Smart Home

80%Available leaks sealed in large single family homes with the aerosol technology.

less than

2 hrs.Time taken to seal the leaks in a home.

up to

13 dBSound attenuation above 800Hz between apartments as a result of aerosol sealing.

27 Number of current installations of the aerosol technology in homes and apartments.

SEALING ENVELOPES USING AEROSOLS

STEP 1 PreparationAssemble, install and

connect controls for

the blower door and

the aerosol injector.

STEP 2 InjectionRun blower door to

pressurize space, and

release the aerosols.

STEP 3 Monitor & ExhaustVerify sealing in real

time, then exhaust

excess sealant when

process completes.

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Rejecting or storing heat into the earth using

geo-thermal pipes is a proven energy efficient

technology. Unfortunately, installation of these

systems are typically cost prohibitive, and the in-

stallation process is not viable on many properties.

Traditional geo-thermal techniques require expen-

sive drilling rigs that can bore vertically 200 feet

into the earth. New alternatives to the traditional

system, such as Large Diameter Earth Bore (LDEB)

and Directional Bore ground source heat pump

(GSHP) installations aim to reduce these costs by

reducing the drilling depth while maintaining an

adequate amount of heat exchange with the earth.

Ground Source Heat Pumps

FIELD TEST: Rio MondegoThis system uses 5 tubes horizontally installed to a

depth of roughly 20 feet in the back yard, yielding

a total heat exchanger size of roughly 130 feet. The

system can drill and install the tubing simultane-

ously, reducing the overall installation time and cost

compared to other systems.

CURRENT FINDINGSup to

20 EER In the summer with the direc-tional bore system installed.up to

6 COP In the winter with the direc-tional bore system installed.

FIELD TEST: Honda Smart HomeThe system uses two different LDEB field config-

urations with 24” wide, 20-foot deep helix shaped

GSHP tubes. Both system installations require a sig-

nificant reduction in time and resources compared

to conventional GSHP systems.

up to

23.7 EER

FIELD TEST: Capay ValleyThis installation uses an LDEB array to store water

that can be cooled during favorable conditions

with an evaporative chiller at night, and then used

to cool a home during the day. Shifting the cooling

demand to night hours increases efficiency and

reduces peak energy consumption.

up to

18% Peak savings in California’s hot climate zones (modeled data).up to

14%

CURRENT FINDINGS

Cooling energy savings in California’s hot climate zones (modeled data).

ADAPTIVE THERMOSTATS DEMONSTRATIONOccupancy responsive thermostats adjust mechanical system operating parameters to reduce energy con-sumption when a conditioned space is vacant.

Up to 25% Cooling energy savings

GALLAGHER HALL BUILDING ASSESSMENT DEMONSTRATIONExamining the whole building sys-tems and analyzing the performance of this LEED Platinum building.

49%

Energy Use Inten-sity reduction vs. similar buildings

ROOFTOP UNIT EFFICIENCY OPTIMIZER DEMONSTRATIONInstallation and performance analysis of an RTU retrofit that utilizes new controls, sensors and variable frequency drive fan motors.

Cooling energy savings

AUTOMATED DUCT SEALING FIELD TESTField installation and performance analysis of the Aeroseal automated duct sealing technology in a 3-story UC Davis building.

19% Energy savings

Technology Demonstrations Program

WCEC’s demonstration efforts highlight market ready HVAC technologies, and pro-

vide a reliable, unbiased perspective on their performance and cost effectiveness.

The technologies demonstrations program is a catalyst for creating best practices

that will inform and guide policy decisions that ultimately impact the broader energy

efficiency marketplace.

Our demonstration activities are public-private collaborations that foster the deploy-

ment of advanced technologies, with special focus on implementing energy efficiency

strategies in coordination with facilities managers and planners at large public institu-

tions such as the University of California, the California State University, the Department

of General Services, and local municipalities.

Download the SPEED reports » http://bit.ly/SPEEDpublications

Up to 51%

CURRENT FINDINGS

The Honda Smart Home analysis is currently ongo-

ing. A larger, previous installation at Parkview Place

in Davis has shown:

up to

6.2 COP

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In air conditioning systems, condensing units reject heat from refrigerant into an out-

side air stream. In these systems, higher outside air temperatures result in higher en-

ergy use by the compressors. As the outdoor air temperature rises, the efficiency of

the air conditioning system drops resulting in more energy use to provide the same

amount of cooling to the conditioned space. Compounding this issue, more space cool-

ing is needed at high outdoor air temperatures due to the increased cooling needs of

the building.

Evaporative cooling in dry climates takes advantage of the outside air’s ability to ab-

sorb moisture, which results in a temperature reduction of the air stream. When evap-

orative cooling is used for pre-cooling condenser inlet air, the condenser operates at

a lower temperature than a baseline air-cooled condenser, and therefore its cooling

capacity is increased, and less electricity is consumed to meet the cooling demand.

There are a large number of manufacturers offering several different designs for

evaporative pre-coolers as retrofits to existing rooftop units (RTU). The design of the

pre-cooler impacts its performance and the resulting energy savings of the air con-

ditioning system. While various field studies have been completed, this project also

conducted laboratory comparisons of performance. WCEC is developing an objective

laboratory test protocol needed to quantify the energy savings, peak demand impli-

cations, and the associated water use of pre-coolers at controlled climate conditions.

Conclusions from this analysis will provide customers with an objective means for com-

paring products.

1. Evaporative Effectiveness: This tracks how close an evaporative cooler can get to the ambient wet bulb

temperature at any given condition. 100% Evaporative

Effectiveness means the cooler can reach the wet bulb

temperature at any given condition.

2. Water-Use Effectiveness: This metric determines what percentage of the water is actually used for evapora-

tive cooling. 100% Water-Use Effectiveness means that no

water is wasted, and all water going into the system is being

used for pre-cooling.

Rooftop Unit Retrofits

EVEN MORE SAVINGS:WCEC is also testing evaporative pre-coolers in combina-

tion with variable speed fan and compressor retrofits. This

combination takes advantage of the reduced ambient air

temperature provided by the pre-cooler, and adjusts the fan

and compressor speeds for even greater energy savings.

EVAPORATIVE EFFECTIVENESS

20-80%

WATER-USE EFFECTIVENESS

30-100%

ENERGY SAVINGSUp to 25%

PEAK DEMAND SAVINGSUp to 30%

LAB RESULTS

WCEC spearheaded ASHRAE’s development of a standard test protocol for evaporative pre-coolers. The protocol is used to

determine two performance defining metrics:

16%Power savings (kW)

RETROFIT WITH A PRE-COOLER

37% COP increase

6gallons

WATER USED PER KWH SAVED

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RETROFIT WITH A PRE-COOLER & FAN/COMPRESSOR OPTIMIZATION

35% Power savings (kW)

51% COP increase

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HVAC TECHNICIAN INSTRUMENT LABORATORY

HVAC technician tools that predict refrigerant properties may be inaccurate, and could account for at least some of the failure to produce expected savings associated with proper maintenance. WCEC laboratory tested 9 different types of monitoring equipment used by technicians and observed their use in the field by technicians.

Results show that most instrument errors were within a satisfactory range, though in some cases, instrument ac-curacy did not meet Title 24 requirements. For the major-ity of use cases, using off-the-shelf HVAC technician tools will enable performance optimization within 1-3% of an HVAC unit’s maximum efficiency.

EVAPORATIVE COOLING MODEL FOR TITLE 24 CREDITS

TRACER GAS AIRFLOW MEASUREMENT SYSTEM

The current status-quo methods for measurement of airflow in HVAC systems are inaccurate and time con-suming. It is especially difficult to measure airflow rates through air handlers and rooftop units. In many instanc-es, physical limitations prohibit the proper use of conven-tional tools such as anemometers, pilot tubes, and flow hoods. Tracer gas airflow measurement is an alternate method for measurement of airflow rates that is much more flexible than traditional methods and can measure between 20-12,000cfm at 98% accuracy—all in one small, convenient package.

WCEC successfully created a commercially viable tracer gas airflow measurement system, and is currently refin-ing the software side experience. UC Davis is seeking a commercial partner to license the technology.

Building simulations are used by builders to predict energy usage and to certify Title-24 compliance. New, evaporative technologies are proven to save significant energy, but there are no reliable simulation modules for builders to realize this savings for Title-24 credit.

WCEC is developing a flexible and re-configu-rable modeling framework that will accurately simulate the performance of these new sys-tems. With a reliable model, hybrid systems can be used within Title-24’s Alternative Calculation Method. This allows building designers and en-gineers to evaluate evaporative cooling as an efficiency measure, while maintaining an overall energy and monetary budget.

GAS ENGINE HEAT PUMPS

Gas Engine Heat Pump (GEHP) systems are relatively new heat pump technology that have a potential for great efficiency. In these systems, the waste heat of fuel combustion can be recovered, reducing overall energy use further. Another benefit of a GEHP is the significant reduction of peak electricity draw compared to conventional systems. Also, ac-cording to our preliminary modeling results, the overall annual operating cost of a GEHP is lower than conventional systems.

PHASE-CHANGE MATERIALS FOR HYDRONIC SYSTEMS

Water is a common, and generally efficient, means for thermal distribution around buildings. However, trans-porting thermal energy by means of a material that changes phase (freezing/melting or condensing/boiling) allows much more energy to be transported by the same amount of material. By pumping a slurry of water and encapsulated phase-change materials (PCM) instead of just water, the increase in heat carrying capacity associat-ed with phase-change means that less of the PCM slurry needs to be pumped to meet demand as compared to a traditional water system.

Lab results show up to a 25% decrease in pumping power for water with PCMs compared to clear water.

CASE STUDIES ON ADVANCED THERMOSTAT FIELD TESTS

This study describes the use of advanced thermostats in-stalled in three non-residential locations. A baseline sur-vey was conducted to measure pre-installation comfort, satisfaction and usability of existing thermostats. The advanced thermostats were installed by contractors, and their usability was assessed by assigning usability tasks to end users and conducting a post-installation survey. Effects on HVAC electricity usage were estimated us-ing SmartMeter and meteorological data collected from comparable pre- and post-installation periods.

Results showed minimal energy savings over previous thermostats, and usability confidence metrics were also much lower. Our efforts indicate that successful applica-tion of advanced thermostats require a more sophisticat-ed deployment process that includes training, commis-sioning and ongoing support.

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Thank you to our Affiliates & Partners

American Honda Motor Co, Inc.®

Belimo®

California Energy Commission

Carel®

Carrier Corporation®

Coolerado®

Daikin Industries, Ltd.®

Davis Energy Group®

E-Source

Evaporcool®

Integrated Comfort, Inc.®

Los Angeles Department of Water & Power

Munters® Corporation®

Pacific Gas and Electric Company®

Sacramento Municipal Utilities District

Seeley International Pty. Ltd.®

Sempra Energy® Utilities

Sheet Metal Workers International Assoc.

Southern California Gas Company®

Southern California Edison®

Tokyo Gas

Villara™ Building Systems

Walmart®

Wells Fargo

Xcel Energy®

wcec.ucdavis.edu