The City of Cape Town, which is responsible for delivering energy to the 4.8 million residents of the Western Cape, has awarded ABB a three-year contract for a phased retrofit of legacy medium voltage (MV) switchgear within its electrical infrastructure.
The new contract follows the success of an initial 2020 project, which saw more than 400, 11kV oil filled circuit breakers and over 100 SF6 insulated circuit breakers replaced with next generation ABB VD4 vacuum circuit breakers, safely disposing of 160kg of potent SF6 gas.
Now the City has teamed up once again with ABB to install additional 12kV VD4 circuit breakers and ancillary equipment to replace their ageing LMX installations. The devices will clear potentially harmful short-circuit faults in tens of milliseconds, preventing severe damage to electrical infrastructure and minimizing the risk of downtime, particularly critical for the Western Cape during planned loadshedding.
Enhanced safety for operators was also a key consideration, with the installation of a type tested Arc-vent door behind which the racking of the circuit breakers is completed.
Frans Bouwer, ABB Regional Manager for the Western Cape, said: “We are proud to be a long-term service provider for the City of Cape Town and delighted to be selected to support them on this milestone modernization project.
“Improving the reliability of the power supply is crucial for the Western Cape but this project goes much further. The City not only invested in an upgrade which would increase the quality and availability of power supply, but also sought a sustainable solution which supported the circular economy.”
Over the past four years, ABB has delivered a range of savings and efficiency gains for the City. By only replacing older legacy circuit breakers, and not the entire feeder board and substation, the upgrades were executed with minimal downtime, while avoiding the costs and emissions associated with replacing the entire switchgear.
Not only did the carefully executed retrofit preserve the majority of the City’s existing installed base, it also prevented the use of an estimated 358,400 liters of oil had like-for-like circuit breakers been used. Furthermore, the project ensured the safe and sustainable disposal of the old SF6 breakers and gases. With one kg of SF6 having equivalent greenhouse effect (or climate change effect) as 23,500 kg of CO2, ABB’s full-circle end of life service ensured that any risk from SF6 disposal was eliminated.
Bouwer added: “Upgrading outdated components is where the largest environmental gains and cost savings can be made – reducing the total cost of ownership by a third, substantially extending the lifecycle of installed assets and minimizing the need for on site maintenance, and associated transport emissions.”
Patrick O’Halloran, Principal Professional Officer: Equipment Standards for the City of Cape Town, said: “ABB’s collaborative approach, combined with their innovative retrofit solution, has been key in successfully continuing the ongoing modernization of our electrical infrastructure, ensuring reliable and sustainable energy to the region and supporting our strong environmental commitments.”
More than half of electrical equipment, such as metal switchgear cabinets, steel plates and busbars, can be used for long periods without being replaced if outdated components such as circuit breakers, relays and internal components are upgraded, regularly monitored and maintained.
ABB’s compact VD4-LMT vacuum circuit breakers are easy and fast to install. The 12KV range includes 630A, 1250A and 2000A circuit breakers type tested at 25kA for 3 seconds. VD4 mechanisms are tested to perform more than 10,000 mechanical operations, delivering increased durability and further reducing downtime.
