Research shows tribology improves energy efficiency

National science academy the Academy of Science of South Africa (ASSAf), completed a study into the state of energy efficiency technologies in South Africa in June this year.

The study, initially commenced by ASSAf in 2016, focused on electrical energy efficiency. However, according to national analysis organisation South African Institute of Tribology VP Patrick Swan, the study included tribology owing to its wide-ranging interdisciplinary focus offering significant prospects to increase efficiencies and reduce energy wastage over a broad range of activities.

Tribology is a wide-ranging interdisciplinary field focusing on friction, wear and lubrication. The ASSAf study considered tribology in respect to three important sectors: energy, manufacturing and transport.

Swan also adds that a previous study completed by Eskom showed that the use of synthetic gearbox oil could reduce the power loss due to friction in gearboxes, and concluded that by converting all major gearboxes in Eskom’s fleet of power generating stations a conservative saving of 20 MW or 140 000 GW/h a year could be achieved.

“Use of synthetic gearbox oil across industry could, depending on uptake, achieve savings of between 200 MW and 600 MW, or over 2 TW/h a year,” enthuses Swan.

He also highlights the Tribology Project 2010 funded by South Africa’s Department of Science and Technology. The project found that upgrading the lowest quality crankcase oils in vehicles, to a more modern multigrade quality would result in savings of between seven-million and 18-million litres of petrol a year.

However – despite studies outlining the potential of tribology in decreasing energy consumption and improving the operational performance of machinery – Swan states that there is still little knowledge across all levels of industry, mining and manufacturing of the proper use of lubricants, and the knock-on effects that can be achieved by using the correct grade of lubricant.

The Tribology Project 2010

According to Swan the Tribology Project 2010 put forth several notable conclusions. It found that local lubricant consumption averages 20% of installed capacity, against an international benchmark of ten percent.

It also found that average drain periods are approximately equal to international standards, which, when considering the high average oil consumption, indicates that equipment failure rates are significantly higher in South Africa. Meanwhile average bearing life has dropped by two-thirds and gearbox lifetime to overhaul by 80% to 90% over the past 20 years. The project ascribes this trend to a lack of skills, resulting in poor alignment during assembly, and excessive dirt entry throughout the supply chain.

“There is general industry comfort with historic failure trends and costs, rather than understanding the root causes,” laments Swan, adding that concentrating on filter element quality and lubricant cleanliness improved hydraulic component life from four months up to seven years.

Swan holds that, “if industry was able to get back to basics and focus on tribology, energy costs could be reduced by between eight percent and 20%, and maintenance costs could be reduced by 30% up to 50%”.

He adds that the reduced production costs will have a knock-on effect in industry, stating that reduced costs will allow for the stimulation of industry in general and will increase employment. Increased employment and local production will increase gross domestic production and will also have a calming effect on workplace conflict.

“Industry that is more globally efficient will increase South Africa’s potential for export which can improve the balance of payments and economic growth,” says Swan.

ASSAf Report Findings

Amongst many other recommendations, the ASSAf report this year concluded that energy efficiency is an economically and environmentally attractive way to meet growing energy demands, but needs support to make a significant contribution as it may not be aligned with the aims of energy producers.

Swan states that South Africa has made significant progress in energy efficiency over the past 20 years, with commensurate savings and increasing competitiveness.

However, he adds that the report suggested that the South African National Energy Development Institute be mandated to develop appropriate policy interventions to consolidate and further develop these gains by ensuring that energy efficiency is a central part of the regulatory framework.

Swan states that tribology research in South Africa has benefitted from the 2013 establishment of a Technical Steering Committee on Tribology that has fulfilled a coordinating role and compiled a tribology “road map”.

“Various recommendations contained in this road map relate to the strengthening of research through the establishment of research chairs and a centre of excellence in tribology,” enthuses Swan.

Specific recommendations stemming from this road map are to strengthen education on tribology by including tribology in the curricula of appropriate disciplines at universities and educating the existing industrial workforce on tribology.

“The study has recommended that collaboration on tribology within the Brics countries be stimulated to leverage Chinese developments in this field,” concludes Swan.