Joburg unveils load limiting initiative

© Scott Norris – 123RF.com

Briefing reporters at Aspen Hills Nature Estate on Tuesday, 14 April, Johannesburg Executive Mayor Parks Tau described the initiative as a flagship for the city.

Through load limiting, City Power will have the ability to inform residents using smart meters of a need to reduce the load on the grid by sending smses.

The sms will advise consumers to reduce power by switching off non-essential appliances. This is done via smart meters which will switch off power if the consumer does not reduce load.

After the consumer has received an sms, the consumer will have 30 seconds to switch off appliances after which the power will go off. This will continue to happen until the consumer heeds the instruction to reduce their power consumption. Once the consumer has reduced the load, power will come back up.

This technology can avert loadshedding.

A total 84 smart meters have been installed at homes in Aspen Hills.

City Power will implement load limiting in two phases firstly on demand when Eskom issues notification to municipalities to shed load due to constrained supply. Secondly, the implementation of load limiting will be scheduled in advance to reduce consumption and reduce the pressure on the grid.

According to the Executive Mayor, the success of the initiative rests on cooperation with communities. "The success of the programme is not only dependent on technology but on residents also being participants," said Tau.

Additionally, the Mayor said that it's important to mitigate loadshedding so as to keep the lights on and to keep the economy of Johannesburg pumping.

The Mayor said that load-shedding is one of the most pressing challenges facing the country.

"We must find solutions. We must all come to the party voluntarily," he said, adding that people can switch off non- essential appliances to mitigate load-shedding.

Load limiting will be done via the 65,000 smart meters that City Power has deployed throughout Johannesburg and when fully implemented load limiting will allow the City of Johannesburg to avert stage 1, 2 and partial stage 3 of loadshedding.

The penetration of 65,000 installed smart meters will yield 153MW for City Power, said City Power Managing Director Sicelo Xulu.

"Load limiting is one of the ways in which City Power strives to ensure that we keep the lights on during periods of constrained supply," he said in his presentation.

An extensive educational drive will be undertaken to educate consumers about the new system before it is fully implemented.

Alongside load limiting, City Power has also implanted a system called Ripple Control which provides the utility with the ability to remotely switch off energy-guzzling geysers during periods when the electricity generating capacity is constrained in order to free up load and avert load shedding.

Ripple control has already been implemented and is still being deployed across Johannesburg.

"Through the implementation of Ripple Control City Power is able to control approximately 110 MW of electricity," said Xulu.