Eskom energises 500 MVA power transformer at 400 kV substation in South Africa December 12, 2016 | Middle East & Africa News South African Eskom Holdings SOC Limited (Eskom) has energised and commissioned the first of the two 500 MVA power transformers at the newly built 400/132 kV step-down Ngwedi substation. This content is available to only paying subscribers. Username or E-mail Password Remember Me Forgot Password