Cold Link Africa May/June 2016 Vol 1 No 5 | Page 31

FEATURE
INCORPORATING COLD CHAIN

Continued from Page 29
racking) may then be problematic, as
they reduce access.”
There are also some great ‘high-tech’
options that can create good order picking
and good space use. One commonly used
system is to ‘pick-to-belt’ – where conveyors
run though the warehouse racking and
operators can efficiently pick cases in bulk
and place them on take away conveyors.
Such systems allow pick rates of well in
excess of 500 cases per hour in the freezer,
but you then need secondary sorting
outside the freezer box.
Energy issues
Increasing energy costs are becoming
problematic for not only automated crane
systems, but all cold stores in general. “South
Africans still aren’t very good at controlling
energy costs,” says Cunningham. There
are stores in Australia that run at 16kWh/
m3 per month. In this country, you won’t
get anything less than 40-45kWh/m3 per
month. “We still use far more energy in our
cold stores than most of the efficient stores
overseas,” says Cunningham.
“Perhaps the best way to ensure
operations use as little energy as possible
is to reduce bottlenecks and improve
product flow,” Bailey suggests.
To cope with organised load shedding,
it’s possibly more cost-effective to have
a generator running the lights, computer
system and the mobile racks rather than
the whole refrigeration system. Because the

disruption really comes from not being able
to move your mobiles and having no lights.
If your refrigeration plant is off for a couple
of hours, as long as you limit your door
openings, you should be okay. “Generally
speaking, I would advise people to look at
smaller generators,” says Cunningham.
PPE
But it’s not just important to have the right
equipment, you also have to make sure
the workers operating the systems and
working in the cold stores are doing their
jobs efficiently – and safely. Having the
right personal protective equipment (PPE) is
critical in a cold store environment and the
importance of a proper freezer suit cannot
be overstated. The dangers of going
between -25°C and 30°C puts a substantial
amount of pressure on your heart, not to
mention other ailments, from constantly
being in such low temperatures. That’s why
you need the specialised clothing.
“If the body’s core temperature reduces
by 0.5°C, which, if you are wearing poorquality PPE, will take less than 15 minutes,
your brain will not function correctly. You
can’t even add,” says Cunningham.
“Definitely not ideal when you’re taking
stock.”
Bailey agrees. At very low temperatures
it is vital to ensure the warehouse staff
are as efficient as possible. Personnel
efficiency is affected by the cold
temperature and the need to ‘warm
up’ regularly. “This is influenced by the
facility design (ease of operation), type

of equipment (does it have proper cold
environmental facilities), and the quality of
clothing used,” says Bailey.
SA vs. the world
Locally there has definitely been a move
towards mobile racking, although overseas
double-deep racking is more popular. This
is a form of high density racking that isn’t
as efficient as mobile but still very popular
because that’s the way it’s always been
done.
“South African cold stores, when it
comes to materials handling, I would say
are far ahead of the Americans and the
Australians,” says Cunningham. “But as far
as refrigeration is concerned and how we
keep our goods cold, we’r