Page 11 - Energize December 2022

INDUSTRY NEWS

A3: Transmission and distribution technogies should we incorporate? Compaction for new lines should be considered,
equipment perhaps more HVDC lines. We need more adoption of new technologies and techniques
by Sibusiso Duma such as HTLS conductors , AI and augmented/virtual reality technologies,worker safety and
The search for SF6 alternatives continues. sensors. There is a lot of opportunity to improve and innovate to ensure that we can build,
Independent institutes, universities and operate and maintain the grid of the future.
the private sector have made efforts
in finding a suitable replacement that B3: Substations and electrical installations
matches all the excellent properties by Philip König
of SF6 at a lower environmental and The Energy Transition to Net Zero is becoming more pivotal to the decisions the electricity
financial burden. We need to accept industry must make. It is clear from the papers and the contributions in the discussion
that there is no absolute answer when meeting, that electricity and the associated infrastructure to deliver it reliably, securely
trying to rank the currently marketed and affordably, will heavily rely, but also impact on, what we do in the Substation
SF6 alternatives, it is rather a question community. There is a need to study the effect on South Africa’s access to spare parts and
that has multiple answers and needs components for older equipment and GIS, as well as the impact of condition monitoring
to be assessed on a case-by-case and circular economy. New design applications include DC substations. Design approach
basis. According to the recent studies impacts carbon credits requiring a joint effort for carbon reduction as it affects the
presented, manufacturers have optimised economy and export competitiveness.
their designs for non-SF6-mixtures, e.g.,
by changing the nozzle, pressure, speed B4: DC systems and power electronics
of contact separation, etc. to solve the by Thomas Magg
issues that different SF6-alternative gases HVDC Technology applications involving long distance power transmission, point-to-point
introduce, and improving, for example, or in parallel with AC networks are important for the future. The integration of renewable
the thermal interruption behaviour and resources must be considered. The increase of IBRs and power electronics (FACTS) in
dielectric withstand capability. AC networks brings a need for better understanding, modelling and study of possible
However, research has not been interferences, interactions etc.
concluded, and many manufacturers
approach this topic in different ways. It B5: Protection and automation
seems the majority are opting for CO 2/CO by Matankiso Mohlokoana
natural gas mixes and vacuum for <132 kV Renewable energy systems are being connected to the grid with an intention of resolving
equipment, and C4-FN mixes for >132 kV the loadshedding issue, but the challenge is that the REs introduce and increase frequency
applications. As all the applications have and voltage instabilities into the power system. This is due to low inertia and a weakened
yet not been covered, it seems too early system strength. We therefore need to look into possible solutions to overcome these
to freeze mixture ratios. challenges – possibly investigate what wide area monitoring and protection schemes
For instance, HV retro-filling of (WAMPAC) can do so that this could be implemented, where required. Vendors and
existing SF6 assets might require a higher Eskom/utilities must have adequate testing and documenting tools for the digital
ratio (20%) of C4-FN than the ones usually substations. Priorities are equipping the design, commissioning, and maintenance staff
implemented in new assets (3 to 6%). For with IEC 6850 and cyber security skills. When implementing full digital substation (MU and
asset managers, it might be ideal to play LPIT), most of the work is to be done in-house from design to commissioning.
it by ear and wait for standardization for
ease of gas handling and associated tools. Group C - Systems
An Advanced High Voltage Disconnector C1: Power system development and economics
Condition Monitoring (ADCM) has been by Jana Breedt
developed, validated and implemented Transmission resilience is a national goal. One way to achieve this is to improve
(both wired and wireless solutions). The infrastructure stability and use operational measures to reduce impact of events
TCO of ADCM is significantly lower than (planned and unplanned) to provide resilience when recovery is needed. Analysing the
the one for conventional HVD, for an impact of extreme events to mitigate risk is becoming increasingly critical, and power
expected service life of 30 to 35 years. system planners and designers should adapt improvement in tools for analysing multi-
Southern Africa could tap into this criteria decision making, investment decisions and testing of scenarios under high
condition-monitoring technology and uncertainty and an exponentially changing energy industry. Resilience studies require the
realise savings from standard time-based synchronisation of multiple-domain information and analysis holistically over the power
maintenance. system. Cooperation, coordination and information sharing between all stakeholders is
an important enabler for Power System development. Regional Interconnectors could
Group B - Technologies provide opportunities for efficient energy utilisation, generation stability support and to
B2: Overhead lines unlock regional economic growth. South Africa has little interconnectivity support. Market
by Sharon Mushabe regulation and diversification of energy mix is critical. Challenges with Covid supply chain
Decarbonisation and net zero emmisions interruptions and the Russian/Ukranian war showed the criticality of diversification and
– how do we contribute, and which regulation.

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