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City Power refurbishing substations to improve the security of supply


City Power’s capital programme expansion and refurbishment has undergone extensive upgrades, to cater to Johannesburg’s current and future electricity needs. The City is growing at a rapid rate because of the migration of the population from peri-urbans into urban areas, it is for this reason City Power has to keep up with increasing demand and replace ageing equipment.
The refurbishment and upgrades on the three substations, at Roodepoort (Roodepoort), Cydna (Melrose) and Nirvana (Lenasia) are one of the ways City Power is working at mitigating power outages and combating energy losses while securing power supply. 
The capital investment into Roodepoort’s new substation is worth an approximate R128 million, Roodepoort is the only substation out of the three to be constructed anew. The station will operate at 3x45 MVA, 88/11 kv with 600m 88kv double circuit lines travelling from Roodetown substation to the new Roodepoort station. Roodepoort’s new substation has installed 2x20MVA 11/6.6 kv power transformers to replace the existing 3x10 MVA 33/6.6 kv transformers at the existing 33/6.6 substation. The existing Roodepoort substation is a high voltage plant supplying residents in Johannesburg’s West Rand, with new customers added to the existing load.
In addition to the capital project programme, upgrades have been implemented at Cydna and Nirvana. The Cydna substation supplies Birdhaven, Melrose and Athol Oakloands areas respectively, at a power generating capacity of 4x45 MVA. The new design will cater for more operational options with both 88kv lines connected on the busbar in addition to the two Rosebank 88 kv cables. An additional benefit of the upgrades is customers fed from Alexandra substation can be back-fed from Cydna, this will minimize the occurrences of outages in those areas. The total budget for the project was R91 million.
Upgrades at the Nirvana substation compromised of 3x40 MVA with 88kv lines. The substation was completely demolished to make way for the new upgrade at a cost estimated at R56 million. The new upgrades will ensure customers from the old board will be transferred into the new board. Thembelihle will be added to the load that is already supplying the Lenasia area. The revamping of both substation’s involved an elaborate asset management plan and network expansion. The energy utility has been working on the substation refurbishments since the 2013/2014 financial year end.
The Managing Director of City Power, Sicelo Xulu said, “These projects came through as a measure to remedy power losses and enhance development in surrounding areas.”  Xulu added, “Continued maintenance and refurbishment of the substations over the medium and long term is an inevitable process we intend on following for the preservation of our infrastructure and networks. The maintenance plan also provides a good opportunity for us to retain some of the staff compliment used for these building projects. Approximately 300 jobs were created from the 3 projects over the 3 year building process.”  At present, construction has been completed on all three sites, once the functionality tests are complete operations can begin.
Securing the sites from theft and vandalism incidents continues to be a high priority for City Power. Xulu said, “To reduce the frequency of criminal activity onsite mini-subs supplying streetlights on main arterials remain encased in steel cages in all substations. Some of the targeted cable circuits have been replaced with aluminium.”
The new substation and upgrades are intended to meet the supply challenges the City has been experiencing over the years. The power that will be distributed from these substations will relieve the impact and the number of incidences of outages on the customer. Non-Technical losses due to the theft of electricity will be significantly reduced because of the new construction and refurbishments, restricting capacity constraints. The completion of the upgrades also means the refurbishment backlog will begin to ease resulting in a better serviced and satisfied customer base.
Cydna Substation supplies: Inanda, Melrose, Melrose Estate, Kent Park, Norwood, Houghton, Houghton Estate, Fairways, Waverley, Killarney, Killarney Mall, Wierda, Illovo East and West Illovo, Killarney South and East, Oaklands, Melrose Arch, Orchards, Chislehurston, Bramley and  Atholl Nirvana Substation supplies: Trade Route Mall, Nirvana, Peri Urban, Nirvana Drive, Gazelle Street, Skate Avenue, Giraffe Street, Bluefin Avenue and Jewel Avenue,Lenasia and Extensions.
Roodepoort Substation supplies: Roodepoort, Roodepoort CBD, Matholesville, Davidsonville, Wilro Park, Princess, Princess Crossing, Tshepisong, Kloofendal, Constantia Kloof, Hyperama and Fleurhof