Major power crisis averted
NamPower MD sheds light on Ruacana shutdown
10 October 2016 | Energy
A nationwide power cut in April averted serious damage to the Ruacana hydropower station, NamPower MD Simson Haulofu says.
On 18 April, the nation was plunged into a blackout and it has now emerged that the power trip was necessary action to avoid a turbine explosion at the Ruacana plant.
A decision was taken to pull the plug after NamPower technicians and engineers detected the error.
NamPower managing director Simson Haulofu told Namibian Sun at the weekend that technicians were assembling the refurbished turbine unit 2 when control officials detected a serious and dangerous fault.
“When the control room detected the hiccup they communicated to all relevant authorities involved and a consensus was reached to trip off the power nationwide to save the power station from exploding,” Haulofu said on the sidelines of the commissioning event of the refurbished power-generating units at Ruacana on Friday.
“We were lucky that stakeholders reached consensus in time, otherwise we would have been in a power crisis now.”
The three units'' refurbishment was done by Ruacana hydropower technicians and according to Haulofu the fault was not a human error, but just a technical problem.
“You are talking about assembling a large sophisticated tool which is computerised. The error was rectified on time despite that power had to come back only after two hours. It is not a system that you just go and switch it back. It has to go through a process of many different regulatory bodies locally and internationally,” Haulofu said.
In 2014 NamPower commenced their first-ever refurbishment works for the turbine units one, two and three which started operation in 1978 and were never serviced. They started with unit one in June 2014 and its operation was commissioned in December 2014, after five days of reliability testing.
In May 2015 they started with unit three whose operation was commissioned in September 2015.
Refurbishment for unit two started in November 2015 and operation commissioned in 24 July this year and while they were busy assembling it in April 2016 they experienced the first and only serious fault.
“This was huge commissioning in the history of Nampower, but we only experienced a single problem which was also rectified on time. In other countries, this could have erupted into a disaster,” he said. NamPower spent N$140 million from their savings for this project.
Haulofu said after refurbishment, each unit has increased power generation with five megawatts (MW) and water discharge efficiency has improved by 10%.
“These refurbishments have increased the station''s power generation capacity effectively by 15 MW, from 237 MW to 252 MW, while improving turbine efficiency allows the station to generate more electricity during low flow seasons. Other improvements include reduced cavitation, vortex flow and consequently vibration,” Haulofu explained.
''No load shedding''
Haulofu also told Namibian Sun that the whole of Southern Africa, including Namibia, was faced with power supply challenges as demand for electricity has exceeded supply. He was, however, hopeful that there would be no load shedding in the next ten years.
“We are now in the driest season and our power generation has decreased by 50%. Our production is mainly during the day while at night we let the dam to replenish and we are producing enough power,” he said.