A deal by South African energy efficiency specialists Rhino Lighting and Powerstar South Africa (SA) has signalled the nationwide roll-out of a globally patented Powerstar range of voltage optimisation systems for local industry, which has resulted in energy cost- savings of more than 25% in some installations.

The collaboration between Powerstar SA and Rhino Lighting comes amid escalating electricity costs in the country, which, in turn, has resulted in businesses’ search for new ways of cutting costs amid stalled economic growth.

“This deal signals further tangible cost savings for big business by removing overvoltage, also known as excess voltage, which is becoming an essential part of companies’ growth strategies as electricity prices soar. It also reduces their carbon footprint and carbon dioxide emissions,” says Powerstar SA owner Edgar Antezana.

The range includes the latest innovation, Virtue, which is an energy storage system that can be integrated with any Powerstar Max or HV Max voltage optimisation system.

The solutions, manufactured at Powerstar’s headquarters in the UK, are designed to deliver significant, guaranteed energy savings for clients, as well as reduce the power bills of big business and industry, says Antezana.

Four voltage-optimisation system installations were completed in July at a leading alloy wheel manufacturer, and a car dealership, in Port Elizabeth; and at two Pick n Pays – in Grahamstown and Port Alfred, in the Eastern Cape.

“This shows the solution works for retail, industrial and commercial settings,” says Antezana.

Other successful Powerstar installations in South Africa include major food retailers, government departments and hotel industry players such as retailer Woolworths and specialist bank and asset manager Investec.

Woolworths Melrose Arch was the first Powerstar installation in South Africa in 2011, while installations for another Woolworths and Investec were completed from 2011 to 2013.

At Woolworths Melrose Arch, independent measurement and verification specialist Energy Cybernetics recorded an 8.27% energy saving over a week following the installation of a Powerstar unit. Another verified energy saving of 12.3% was achieved on the load for the air-conditioning system following installation at the Investec headquarters in Johannesburg.

Additionally, savings of 20.71% have been achieved following the installation of a Powerstar unit at the Manhattan Boutique Hotel in Pretoria, Gauteng, in August 2013, while energy savings have ranged from between 7.7% and 12.8% in other retail store installations.

Powerstar system inventor Dr Alex Mardapittas says the “unique, patented designed voltage optimisation system returns the excess voltage in terms of negative power, which is subtracted from the grid input power.

“Between 70% and 80% of the total savings are derived from the negative power feedback, while 20% to 30% are derived from the improvement in equipment efficiencies,” he notes.

Rhino Lighting MD Heather McEwan further explains that State-owned power utility Eskom typically delivered electricity at higher voltages than was required, suggesting that this is done to “balance out losses that occur along transmission lines” and ensure that the end-user receives the minimum 220 V required to operate machinery and equipment.

For end-users to receive this standard voltage, users situated closer to the transformers often received much higher voltages than they needed, says McEwan, noting that companies were paying for that additional voltage and had to deal with the financial effects of increased equipment failure.

Further, a 230 V linear appliance using a 240 V supply would take 4.3% more current and consume almost 9% more energy while only achieving about 55% of its rated life span, says McEwan, referring to a statistic from technical professional organisation the Institute of Electrical and Electronics Engineers.

McEwan consequently posits that Powerstar is unique, in that it was designed to ensure that savings could be achieved regardless of the type of energy load to which it is connected.

“We stand by the guaranteed savings provided on all Powerstar systems and will refund the difference if the saving in kilowatt hours, which is calculated by the Powerstar engineers, is not achieved,” she says.

Savings could also be achieved on light- emitting diodes or variable-speed drives that have been installed to improve energy efficiency, McEwan concludes.