CONTRIBUTORS
INCORPORATING COLD CHAIN
technology, to start incorporating the ammonia-based systems to some
knowledge gained in overseas markets, degree. However, he also says that
and produce solutions that fit the unique the challenges listed above are
requirements of the South African market. manageable, and great strides have
THE FLAWS OF R717
At the same time ammonia does pose a
couple of challenges at present. Firstly,
already been made in the industry to
realise the full potential of ammonia-
based solutions.
high concentrations, meaning that any UNLOCKING THE
POTENTIAL OF R717
refrigerant leak in the system carries a Globally, the drive to further develop the
potential safety hazard. This is one of the capabilities of R717 systems is gaining
reasons why R717 systems are mostly significant momentum, and the safety
limited to industrial applications, and why concerns surrounding ammonia gas
the commercial market still tends to shy is one of the top areas of focus. The
away from this solution. toxicity and volatility of ammonia is the
ammonia is toxic and flammable in
Secondly, while ammonia is well
main reason why it is mainly utilised in
suited to mid-temperature cooling (5°C operations that are not located near
to -30°C), it underperforms in very low the general public. In response to this,
temperature applications (-35°C to -50°C) a lot of work has been done to reduce
where CO 2 is still a better performer. the amount of R717 that is actually
especially in the South African market, is refrigeration for each application.
Another negative aspect of ammonia,
the fact that these systems traditionally
Industrial ammonia plant room.
required to achieve the desired level of
The use of direct expansion systems
the use of air-cooled condensers in higher comparison between ammonia and
ambient climates. the other promising natural refrigerant,
rely on evaporative condensing. with very accurate vapour quality control, Naturally, this is a real problem in the allows one to reduce the ammonia world’s most prominent companies are of expertise in South Africa. Certainly,
South African context, where reducing charge (and vessel size) without losing also endeavouring to reduce the capital water usage has become one of the energy efficiency. cost of ammonia-based systems. There CO 2 systems are competitive with
biggest priorities for businesses, next to
electrical efficiency.
Together with the higher initial capital
From a cost point of view, some of the
The development of hybrid and air- has been some progress in developing of maintenance over the life span of the
systems that incorporate a secondary system will most likely be higher, since
refrigerants have also helped to address refrigerant such as CO 2 alongside there is a comparatively smaller skills pool
the issue of high water use. R723, a blend
play a role in limiting the market for of ammonia and dimethyl ether, allows
ammonia as a primary driver, to achieve
lower temperatures while still containing
has also been made in introducing smaller viable solution for large-scale operations
compressors into the ammonia market, (550kW applications and higher).
effectively cutting down on the footprint With this in mind, service providers in
of the equipment, as well as the amount South Africa should take the time to bring
of refrigerant required. This opens up more the message of long-term cost-effective
possibilities to start utilising ammonia, even operation across to potential clients. As
in commercial applications. part of driving the notion that ammonia-
based refrigerants are the best solution
for the South African market, our industry
One final obstacle that R717 systems face needs to start pushing the message that
in South Africa today is that of perception, the long term benefits of these systems far
as ammonia-based refrigeration systems outweigh any upfront capital costs – which
are still considered more costly than many only represent around 15% of the cost of
other solutions. the system throughout its total life cycle.
Naturally, EP Refrigeration also has
is still between 10% and 20% higher than extensive experience in R717-based
traditional CFC and HCFC units. We have systems. All of the systems that we
unfortunately seen that some companies currently design and supply under EP
are discouraged by this. However, if Refrigeration’s Multistage brand are
viewed from a life-cycle perspective, it ammonia-based solutions. As a company,
becomes clear that the capital outlay is we have built up a huge base of expertise
only a small part of the total cost of any around this technology specifically, and
system. The cost of maintaining ammonia- we do quite a significant number of new
driven systems is objectively lower than installations each year.
with synthetics, and they also have an The potential for ammonia as a
effective life cycle of around 25 years, refrigerant is so much greater than its
as opposed to the 10 to 15-year life span current applications in South Africa,
of commercial systems used for CO 2 , and this is something of which the
propane and synthetic refrigerants.
The energy efficiency also plays a
market should become much more
aware. The technology has evolved
massive role, as electricity use makes up to such an extent, that we believe
a minimum of 60% of the life cycle cost R717-based systems should be the first
of any given system. Modern ammonia- option to be considered in virtually any
based systems require around between industrial application and certainly a
5% and 15% less energy to operate good contender in larger commercial
compared to traditional synthetic and applications. If the industry in South Africa
CO 2 trans-critical systems, which adds up continues to drive better innovation, there
to significant savings over 20 years.
The long-term benefits of these systems far outweigh any upfront capital costs.
to say that CO 2 has no place in the South
African market, but it is certainly a less
The cost of installing ammonia systems
R717-based systems can be considered for virtually any industrial application.
than in the case of ammonia. This is not
the initial cost of the system. Advancement
CHANGING PERCEPTIONS
OCTOBER 2019
ammonia in terms of price, but the cost
cooled condensing systems for ammonia cost, these drawbacks continue to
COLD LINK AFRICA •
CO 2 , you have to look at the availability
In addition, when making the
could also be no limit to what this versatile
refrigerant can achieve.
CLA
www.coldlinkafrica.co.za
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