FEATURE
INCORPORATING COLD CHAIN
The rise and rise of CO 2
Compiled by Ntsako Khosa
Owing to the gradual increase of CO 2 in the industry, especially in supermarkets globally, we
look at the performance thereof down the line.
CO 2 REFRIGERANT GROWTH
CONTINUES
Transcritical CO 2 systems have also been
part of displays at recent expos, such
as AHR Expo, for instance. Research
suggests that this will further occur in
many other areas crossing various layers.
According to Refrigeration veteran,
Peter Powell, CO 2 as a refrigerant
has been a part of the refrigeration
landscape for close to two decades
— from early efforts combining it with
ammonia in cascade systems for
industrial plants, to cascade and other
approaches with HFC refrigerants in
supermarkets.
The most anticipated next step was
running CO 2 as a standalone refrigerant
in a system, which is being done in
Europe in more and larger applications.
Finally, the approach crossed the
Atlantic and made a high profile debut
in Brooklyn, New York.
STATESIDE
During a press briefing hosted by Danfoss
Food Lovers Market.
at the AHR Expo in New York City, Mike
Ellinger, director of global maintenance the products it sells, but in how it
and refrigeration for Whole Foods, talked about the transcritical CO 2 store across
the East River.
“Whole Foods Market is committed to
Ellinger said challenges included “higher
designs, builds, and operates its stores,” a booster CO 2 system with subcritical compressors on low temperature and initial system cost compared to a DX
he said. “We practice and advance transcritical on the medium temperature system, navigating permit requirements,
environmental stewardship.” side. The Danfoss collaboration included lack of language in codes, and
He noted 11 existing Whole Foods VFDs, rack control, system control, case unexpected costs due to regulatory
stores with various types of CO 2 systems controls, pressure independent control modifications.” This relates to an ongoing
supporting the health of its customers including the 56 000 sq. ft (5202m²) store valves, solenoid valves, and heat and team members, not only through in Brooklyn. He said that the store uses exchangers. issue regarding CO 2 as many of the
reducing its environmental impact and
technological advances are ahead of
municipal code modifications.
The ultra-efficient,
low charge ammonia
chiller has delivered
incredible energy
savings and reduced
carbon emissions.
Since the store had only been open a short
period at the time of the presentation,
Ellinger said, “We need six months-plus of
analytic data to compare performance.”
He also said Whole Foods will share a
one-year report regarding the CO 2 system
performance. In a detailed case study
released a year after installation, Tristam
Coffin, director of Sustainability & Facilities
for Whole Foods Market's (WFM) Northern
California Region. stated that when it
comes to installing natural refrigerant-
based systems in supermarkets, there is no
Evergreens Fresh Market.
COLD LINK AFRICA •
March/April 2020
one ‘silver bullet’ solution for every store.
www.coldlinkafrica.co.za
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