Page 33 - Energize November 2022

VIEWS AND OPINION

Seraphim, with a capacity of 500 MW/annum. Both use highly a huge difference in the viability of an PV industry in this country,
automated processes for the production and have plans for although the industry would still be dependent on imported raw
expanding capacity. Establishing a local industry would require silicon.
producing the wafers that make up the core of the module. A few decades ago, there were numerous manufacturers
Solar Panel assembly has been an industry for a long time using the PCS ingot casting method, who produced a quality
in SA. Going back several decades there was Helios Solar in product, albeit with a lower efficiency than mono. Among them
Pretoria, making 50 W polycrystalline panels, Total Solar in were Solarex in the US, BP in Australia, and Photowatt in France.
Cape Town, and a number of other companies who have since Product from that era is still in use in this country.
disappeared. The fact is that there is the capability to assemble
PV panels in this country, mainly to serve the utility market. Wind
Small wind turbines
Wafer manufacture SA has an indigenous small wind turbine manufacturer, Kestrel,
Currently all high-performance PV modules are monocrystalline which manufactures locally designed units up to 3,5 kW capacity.
silicon (MCS). The process for producing monocrystalline The product is well established in the South African market
silicon is complex, requiring a large investment. Manufacture as well as further abroad. The product serves off-grid and
of polycrystalline (PCS) is simpler as it uses a simple casting agricultural applications, where it is popular for off-grid telecom
process to produce rectangular ingots or “bricks” which can be sites, water pumping and other agricultural applications.
processed easily. Major manufacturers still feature PCS as part
of their product line. Large wind turbines
The disadvantage of PCS is that the efficiency is lower, but Several attempts have been made to establish a large wind
for many applications such as small rooftop system using a few turbine industry in South Africa, and some success was achieved
panels this could be offset by the lower cost, and PCS panels with the manufacture of towers. The IDC has shown an interest
are popular for rooftop and other small solar systems. in reviving the wind turbine tower manufacturing plant in Coega
The ingot casting process has advanced over the years. It is and in the industrialisation of the SA wind industry. There are
now claimed to be possible to produce quality monocrystalline reports that the local assembly of wind turbines is considered
ingots of the same quality but at a cost approaching to be a starting point, which seems odd since wind turbines are
polycrystalline. No commercial plant is operating as yet but already imported in pieces and assembled locally.
there is a growing interest in the process in the market. In 2015, the Department of Trade and Industry (the DTI)
Seraphim, in 2020, expressed an intention to consider published a 195-page document entitled “The wind energy
establishing a wafer casting facility in its East London factory. industry localisation roadmap in support of large scale roll out
Recent conversations with a representative at the Solar Show in South Africa” which gave detailed analysis of the potentials
2022 confirmed that the facility was still a possibility, but no and problems. Nothing seems to have happened since then. The
dates have been given. If this facility materialises it would make document however contains some interesting information on
local content.
Of the total cost, 45 % consists of balance of plant, which
is comprised of the foundation, transport and erection and
electrical plant. These are comprised of local items which existed
prior to the wind industry and should not be included when
calculating local content. Of the turbine costs, that make up 55%
of project cost, the blades comprise 16,5%, towers comprise
25,8% and the total nacelle 55%.
Wind turbine nacelles are the heart of the turbine, like
the engine room on a ship, and house critical components
such as the gearbox, main shaft, generator, transformer and
electrical cabinets, many of which can be locally assembled and
manufactured by existing industries. The nacelle is therefore the
most viable component, as manufacturing plant could be used
for any size of wind turbine with minor retooling.
The problem components are the blades, as the blade
moulds can only be used for one size of blade. If more than one
size is envisaged, then additional moulds are required, as it will
Figure 1: Silicon feedstock be a long time before 3D printing of turbine blades happens. This

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