WHETHER companies need power to survive loadshedding or to raise their production output, the trend is for these power generating systems to get bigger.
According to Bernard Mitton, Business Development Consultant at Zest WEG, it is becoming more common for customers to request proposals for power solutions that exceed 10 MW. In South Africa, this appears to be mainly a response to rising levels of loadshedding. In other parts of Africa, says Mitton, it is economic growth that drives demand.
“For many companies who want to grow their output, it is vital to have continuous and reliable power supply,” he says. “In recent years, Zest WEG has been designing and installing more of these large power plants for customers across Africa.”
It is Zest WEG’s depth of in-house engineering expertise and technical capability that earns it these contracts, he explains. From the generator sets themselves to the transformers, switchgear and containers, the company can provide customers with a full turnkey solution.
“We often propose a modular system that allows the customer to execute their project in phases,” he says. “They can begin with the most cost effective solution, and then expand the plant as the power demand grows.”
In one of these 10 MW systems, there will usually be eight to 10 generators installed within a containerised solution or a dedicated power plant room. They can generate power at 400 V, to be stepped up by transformer up to 11 kV – or power can be generated directly with an alternator output up to 11 kV.
“For a typical 10 MW power plant, we connect the generators to a common switchboard up to maximum 22 kV, to distribute power to the various on-site loads,” he says. “The switchboard solution can be installed in a container, an E-house or a plant room.”
The generating units are custom engineered, built and fully tested in Zest WEG’s Cape Town generator facility. Testing includes a step load test and the synchronisation of generators to each other – verifying all setpoints, engine performance and efficiency indicators.
