Guides
Practical things, laid out plainly. What it costs and how it works.
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Beyond capacity: the engineering behind Nnewi’s 800 MVA transmission hub
How multiple transformers and interconnected systems create flexibility inside Nigeria’s power grid — and why the headline number is the least interesting thing about the station.
03 AUG · Nnewi · The Signal · 8 min read
- 31 JUL · Nnewi
How electricity moves through the Nnewi 330/132/33 kV transmission substation
Power enters the Anambra station at the highest transmission voltage in the country and leaves at 33 kV. Between the two are line bays, a busbar, two stages of transformation — and a set of choices about which path it takes.
- 03 FEB · Kwara
How the Kwara 330 kV substation was built from an empty site into a working grid facility
Before a transmission station can move a single megawatt, the work is civil, not electrical. Foundations, trenches and an earthing grid come first — and the equipment everyone photographs arrives last.
- 30 JAN · Kwara
How electricity enters the Kwara 330 kV transmission substation
Four 330 kV line bays feed the station. Before power reaches either 150 MVA transformer, it passes through a controlled sequence of protection, measurement, switching and isolation.
- 28 JAN · Kwara
What two 150 MVA transformers do at the Kwara substation
Two 150 MVA units move power from the 330 kV system into the 132 kV and 33 kV networks. Together they hold 300 MVA of installed capacity — but the second transformer buys something the first cannot.