EVENTS AND EXHIBITIONS
INCORPORATING COLD CHAIN
He also spoke about thermal abuse for a
while, which inevitably minimises storage
and shelf life as well as value of the product.
Prof. Dodd also looked at refrigeration
efficiency and ways to save energy, such
as putting doors on fridges in supermarkets.
Cold Cubed has invented a live
temperature dashboard that could prevent
loss of shelf life. It enables a retailer to see
all its stores nationwide. “We need end-to-
end solutions,” he said. “We need to be
mapping supply and demand. We need to
alert food nearing expiry date.”
“Cold chains are complex and
consume large amounts of energy,” Prof.
Dodd said in his closing statement. “They
must be well managed to ensure seamless
movement of temperature-sensitive stock.
The ultimate goal is to ensure quality and
shelf life that will mean profitability for all
those involved.”
MINE COOLING AND
FINANCIAL SUPPORT
The next speaker was Philip Maré of the
Centre for Research and Continued
Engineering Development (CRCED) in
Pretoria, who spoke on ‘Mine cooling: is
it technically fully matured or are there
opportunities?’.
After his talk, delegates enjoyed a short
break before heading into the second
keynote session of the morning. Thuthukile
Mthetwa of the Technology Innovation
Agency (TIA) spoke about the financial
and non-financial support TIA offers for the
development of innovations in the energy
space in South Africa and its funding
requirements, among other aspects.
The agency is currently allocating most
of its funds to fuel cells, followed by energy
management in terms of air conditioning.
REFRIGERATION SYSTEMS
Dawie Kriel, director at Energy Partners
NRGP Refrigeration, addressed delegates
on the topic of ‘Energy efficiency and
operational savings in refrigeration systems’.
“Refrigeration is essential to the existence
of modern society,” he said. “Seen in the
context of energy use, it is one of the top
consumer technologies in use. It clearly
makes sense to provide refrigeration in an
energy-efficient manner.”
But he first went back to basics. “If you
want to save energy, it is very important
that you understand the basics of
thermodynamics,” he said. He also spoke
about what coefficient of performance
(COP) means and how it works. “To save
energy in refrigeration systems, we have to
strive to reduce the difference between
the effect on suction temperature and
food safety,” he said. He emphasised
that although it preserves the quality of
products, it is important to remember that it
cannot improve quality. But the cold chain
does extend the practical storage life of
that product. “Without it, we could never
distribute products over vast distances,
have time for marketing, and export
the large volumes of perishables that
contribute towards the economy of South
Africa,” he said.
An attentive audience during the conference as students and industry role players
came from far and wide to attend the important annual event.
condensing temperature (or pressure),”
he advised.
But it wasn’t all about the theory
with Kriel. Drawing on seven years of
experience with practical implementation
of cost reduction projects in this field,
Energy Partners has reached some
interesting, but not unexpected,
conclusions. He shared some thought-
provoking case studies and their findings,
particular to the South African context.
“The number one enemy of energy
efficiency is the mantra ‘we have always
done it like this’,” said Kriel. “There is no
magical answer to reducing energy
consumption significantly; it requires logic
and many small interventions.” But he did
have a few suggestions/tips:
• The most common opportunity they
found in practise was the lack of basic
maintenance. Generally, fixing this
improves energy efficiency by 10%
or more. He gave some practical
examples like correct refrigerant levels
and fixing defrost cycles.
• Minimise the differ ential between
suction and discharge pressure and
reduce parasitic losses.
• Improve control systems and implement
system information reporting.
•
•
•
All parties in the chain have the
responsibility to shift their focus away
from cost and consider life cycle
cost first.
Information systems providing digestible
data to plant users and operators must
be installed and acted upon.
Global warming and rising energy
costs are a reality and therefore, the
shift to natural refrigerants are here
and unavoidable.
LOOKING AT TRANSPORT
The last keynote presentation before
lunch was done by John Ackermann on
behalf of the Southern African Refrigerated
Distribution Association (SARDA). His talk
focused on the cold chain and energy
savings in transport.
“The cold chain is of tremendous
importance for our well-being and
Ackermann looked at the variety of
refrigerated road vehicles currently on our
roads, before focusing on the source of
heat loads in refrigerated vehicles.
He covered topics such as factors
affecting the U-factor of a new vehicle as
well as those in service. You have to look
at the heat load versus energy versus food
safety, he advised. “The cooling capacity
of the transport refrigeration system must
be able to handle the heat load.”
He then spoke about the new thermal
test chamber recently completed at the
SABS for testing the thermal efficiency of
refrigerated bodies. He showed some
pictures of the chambers and the plant,
explaining why it is important to test these
bodies accurately.
Ackermann’s talk covered things like
the plating and marking of vehicles to
indicate the thermal rating. He also spoke
on the ATP (formally, the Agreement on
the International Carriage of Perishable
Foodstuffs and on the Special Equipment
to be used for such Carriage) and the
significance of this for the local industry.
It is estimated that we have over 3 000
refrigerated trailers in South Africa and none
have been certified in terms of thermal
performance. It is believed that they are
Kriel drew the following conclusions:
• 10% energy savings are immediately
achievable on most existing plants if
we ask the right questions.
•
•
Most energy-saving interventions require
little capital investment, with good
maintenance at the top of the list.
Optimising design and control in
addition to concepts such as waste
energy recovery can increase savings
to 30%, with a payback period of less
than four years.
Old friends catching up, from left: Prof. Phillip Lloyd (CPUT); John Ackermann (SARDA);
and Prof. Jasson Gryzagoridis (CPUT).
COLD LINK AFRICA • November | December 2017
www.coldlinkafrica.co.za
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