case studyWal-Mart Bakersfield

Wal-Mart is one of aMerica’s largest

retail outlets With over 6,000 stores

across the country. With this size of

corporation, they are acutely aWare

of the costs of air conditioning their

stores to provide coMfort for their

custoMers all year round.

With this in mind, Wal-Mart has established a dedicated

team to pursue energy efficient ways to manage their

business and, as HVAC is one of the largest consumers

of energy, the team explores many ways to reduce their

dependency on it.

Wal-Mart installs Climate Wizard at Bakersfield, California

The Bakersfield Super Store sits in an agricultural area in

central California and is subject to long hot summers that

make air conditioning essential. Here Wal-Mart chose to

retro-fit Climate Wizard to save energy, by using the unique

characteristics of Climate Wizard to pre-cool the outside

air that is introduced to the store, therefore unloading the

refrigerated systems that were already installed.

The installation of three Climate Wizard model CW-H15,

directly coupled to existing Roof Top Units (RTUs) proved

to be a simple and quick installation. In order to properly

evaluate the performance of Climate Wizard, the assembly

of RTU and Climate Wizard is being independently

monitored with daily information being recorded for analysis.

Quality ISO 9001

Seeley International Europe (Italy)

Via Rigutino est, 194 52100 Rigutino (AR) Italy

Phone +39 (0) 575 97189 Fax +39 (0) 575 1949971

Email marketing@seeleyinternational.com Web seeleyinternational.com

The graph (overleaf) shows that on a hot day, when it

reached 103°F (39.4°C) on the roof, Climate Wizard was

delivering cool air at 65°F (18.4°C). This means that

Climate Wizard was operating at an incredible EER of 54

(COP = 15.8). Compared to a commercial refrigerated

system, that is over five times more efficient.

Independent testing by the University of South Australia*

established that as the outside ambient temperature rises

from 35°C to 44°C the cooling capacity of a refrigerated

system falls on average by 17%, while the total cooling

capacity of Climate Wizard in this configuration, increases

by 40%.

The retrofitting of Climate Wizard to a refrigerated RTU is

therefore a powerful combination that will work to maintain

cooling capacity in even the hottest weather.

In the Wal-Mart installation, the super efficiency of the

Climate Wizard in providing cool air, even on the hottest

days, reduces the requirement for the costly operation of

the refrigerated compressors.

*On-Site Testing of Climate Wizard at Roxby Downs, University of South Australia.

above: in order to fully integrate the economiser (outside air cooling by climate Wizard with the normal rtu function) a plc was employed with dictated system response to climatic conditions and the indoor heat load.

this allows flexibility in use and maximisation of the energy savings.

Benef its � exceptionally loW cost of

operation, With an eer of 54 (cop 15.8)

� loW Maintenance costs and long life equipMent

� retro-fit installation, suitable for all rtus

� enhanced coMMitMent to the environMent

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BAKERSFIELD WALMART (RTU 16) 20 JULY 2013

Installation Original New

System 70kW PAC CW-H15 + 70kW PAC

Cooling Capacity 70kW 28 + 70 = 98kW

Input Power at 70kW

25kW 16.2kW

COP (EER)* 2.8 (9.6) 4.3 (14.7)

Power Saving* - 35%

*At design conditions

Project information