Latest News Archive

Please select Category, Year, and then Month to display items

Study on solar energy compares well with current state-of-the-art research in the field

01 March 2024 | Story Leonie Bolleurs | Photo SUPPLIED

“I like taking what I have learned from literature and going to the laboratory to test it. Sometimes the results surprise me, leading to additional experiments or refining. This process could continue for several months and even years, with me slowly building the puzzle. And finally, one day, all the pieces come together, and everything becomes very clear to me as a physicist. And if I am lucky, I will have the privilege of knowing a secret about nature that nobody else has known up to this point. However, as an innovator, I am tasked with using this new knowledge to develop ways to manipulate nature to deliver a helpful device.”

These are the thoughts of Dr Lucas Erasmus, Junior Researcher in the Department of Physics at the University of the Free State (UFS), who has just returned from Ghent, Belgium, where he had his public defence of a joint PhD with Ghent University, titled: Luminescent solar concentrators – where Sm2+ doped phosphors shine.

The research project is part of a bilateral collaboration between the Department of Physics at the UFS and the Department of Solid State Sciences at Ghent University. In this study, the strengths, experience, and resources of both research groups – experienced in developing luminescent materials for various applications – are used to ensure a stronger final product. To meet the requirements stipulated in the cooperation agreement between the two institutions for the joint supervision and certification of Dr Erasmus’ doctoral studies, research was conducted both at the UFS and at Ghent University.

Dr Erasmus’ research is significant in the light of rising energy prices, energy scarcity, and the pursuit of a carbon-free society, where there are strong incentives to develop new and renewable energy sources.

Combining windows and solar cells increase their relevancy in many applications

He says that although solar panels play an essential role in renewable energy – since they provide a route to directly convert solar radiation into electricity – there are limitations to installing conventional panels, which are bulky, rigid, and opaque. He believes that combining windows and solar cells could increase their relevance in the built environment, agricultural sector, and modern consumer electronics.

Explaining about the luminescent solar concentrator (LSC) in his study, he states that it is a device used as a large-area solar radiation collector that converts and emits radiation. The emitted radiation is directed to photovoltaic cells located in the small side area of the device. According to him, a basic LSC consists of a transparent waveguide with an embedded luminescent material and a strategically placed photovoltaic cell on the edge.

Dr Erasmus continues, “The large area of the waveguide collects a portion of the solar radiation, while the luminescent material absorbs the energy and downshifts it to longer wavelengths. Internal reflection directs the emitted photons towards smaller areas on the sides where the photovoltaic cells are used to convert the concentrated light into electricity.”

In his view, creating a large and efficient LSC is a challenging endeavour that requires an in-depth study of multiple domains. “This includes developing and optimising the luminescent material, studying its behaviour and the characteristics of the waveguide, and finally adding these two components and developing, characterising, and simulating the hybrid device,” he remarks.

“While the current prototype we have developed delivers good results, it is still far from perfect and not commercially viable,” he says, stating that this study could, however, serve as a guide for future researchers interested in developing LCSs. Dr Erasmus believes the underlying science behind the results contributes to a general understanding of the materials, making this study valuable to other fields and contributing to the larger body of science. At the end of the study, he also makes some recommendations for future research in this field.

Study a reflection of theoretical knowledge and a practical system

The public defence consisted of both an internal and an external defence. The internal defence took place in January at the UFS between Dr Erasmus and the examination committee. The external defence occurred at Ghent University and was also open to the broader public. Also present at this event in Belgium were colleagues from the UFS – Prof David Motaung, an examiner; Prof Koos Terblans, co-supervisor; and Prof Hendrik Swart, supervisor for the PhD thesis.

Dr Erasmus’ experience of the oral examination was that the examiners were primarily positive in their critique but also thorough in their questioning. According to him, some of their remarks pointed out that they were impressed with the meticulous planning, execution, and interpretation of the experimental results and that the researchers involved ensured that any parameter that might have influenced the device was maximised. “Moreover, they liked the fact that I went all the way from theoretical knowledge to a practical system. The examiners also noted that the study compares well with the current state-of-the-art research in the field,” adds Dr Erasmus.

He says that having the public defence in Belgium was a once-in-a-lifetime experience, allowing him to interact and deliberate directly with the examiners and communicate their findings and conclusions to the broader public. Dr Erasmus hopes that this will lead to stronger collaboration and better public sentiment toward spending funding for scientific projects.

For future steps, he states, the research group involved in the project plans to continue this research by further increasing the device's efficiency. “To this end, we have already developed another luminescent material that can address some of the challenges we encountered while developing the first prototype device. This forms part of the work that Johané Odendaal is doing in her master’s degree, of which I am a co-supervisor. We also plan to enlarge the scope of our research to consider the challenges that are currently hampering the next generation of photovoltaic cells and to find ways in which we could address these issues,” comments Dr Erasmus.

News Archive

UFS to investigate implementation of quality-monitoring system for SA food industry

2006-02-07

Some of the guests who attended the workshop were from the left Prof James du Preez (Chairperson: Department of Biotechnology at the UFS); Prof Lodewyk Kock (Head: South African Fryer Oil Initiative (SAFOI) at the UFS)); Mrs Ina Wilken (Chairperson: South African National Consumer Union (SANCU)); Prof Herman van Schalkwyk (Dean: Faculty of Natural and Agricultural Sciences at the UFS) and Mr Joe Hanekom (Managing Director of Agri Inspec).
Photo: Stephen Collet

UFS to investigate implementation of quality-monitoring system for SA food industry

The University of the Free State (UFS) will be investigating the implementation of a quality-monitoring service for the South African food industry.

This was decided during a workshop to discuss the external quality monitoring in the edible oil industry of South Africa, which was recently held at the UFS.

Major role players in the fast-food sector like Nando's, Spur, Captain
Dorego's, King Pie Holdings, Black Steer Holdings, etc and various oil
distributors like Felda Bridge Africa, Refill Oils, PSS Oils and Ilanga Oils attended
the workshop. Also present was Mrs Ina Wilken, Chairperson of the South African National Consumer Union (SANCU) and key-note speaker of this workshop. She represented the consumer.

These role players all pledged their support to the implementation of this quality- monitoring system for the whole food industry.

The decision to implement this system follows the various malpractices reported in the press and on TV concerning food adulteration (eg the recent Sudan Red Scare), misrepresentation (eg olive oil scandal exposed in 2001) and the misuse of edible frying oils by the fast-food sector.

“One of the basic rights of consumers is the right to safe food. Consumers must be protected against foods and food production processes which are hazardous to their health. Sufficient guarantee of the safety of all food products and food production processes should be implemented. It does not help to have adequate food standards and legislation and there is no manpower to do the necessary investigation or monitoring,” said Mrs Wilken.

The South African Fryer Oil Initiative (SAFOI), under the auspices of the UFS Department of Microbial, Biochemical and Food Biotechnology, currently monitors edible oils in the food industry and makes a seal of quality available to food distributors.

“Last week’s decision to implement the quality-monitoring system implies that we will now be involving also other departments in the UFS Faculty of Natural and Agricultural Sciences who are involved in various aspects of the food chain in an endeavor to implement this quality monitoring system,” said Prof Herman van Schalkwyk, Dean: Faculty of Natural and Agricultural Sciences at the UFS and one of the main speakers at the workshop.

Prof van Schalkwyk said that the main aim of such a system will be to improve the competitiveness of the South African food industry. “It is clear that the role players attending the workshop are serious about consumer service and that they agree that fraudulent practice should be monitored and corrected as far as possible. Although some of the food outlets have the capacity to monitor the quality of their food, it may not seem to the consumer that this is an objective process. The proposed external monitoring system would counteract this perception amongst consumers,” said Prof van Schalkwyk.

The workshop was also attended by representatives from SAFOI and Agri Inspec, a forensic investigation company collaborating with inter-state and government structures to combat fraud and international trade irregularities.

Agri Inspec has been working closely with SAFOI for a number of years to test the content of edible oils and fats. “Extensive monitoring and control actions have been executed in the edible oil industry during the past four years to ensure that the content and labeling of oil products are correct. Four years ago almost 90% of the samples taken indicated that the content differed from what is indicated on the label. This has changed and the test results currently show that 90% of the products tested are in order. However, to maintain this quality standard, it is necessary that quality monitoring and educational campaigns are continuously performed,” said Mr Joe Hanekom, Managing Director of Agri Inspec.

“The seal of quality presented by SAFOI should also be extended to include all the smaller oil containers used by households,” Mrs Wilken said.

The SAFOI seal of quality is currently displayed mainly on some oil brands packed in bigger 20 liter containers, which include sunflower oil, cottonseed oil, palm oil etc which are used by restaurants and fast food outlets. “Any oil type is eligible to display the seal when meeting certain standards of authenticity. In order to display the seal, the distributor must send a sample of each oil batch they receive from the manufacturer to SAFOI for testing for authenticity, ie that the container’s content matches the oil type described on the label. This is again double checked by Agri Inspec, which also draws samples countrywide from these certified brands from the end-user (restaurant or fast food outlets). If in breach, the seal must be removed from the faulty containers,” said Prof Lodewyk Kock, Head of SAFOI.

“It should however be taken into account that oils without a seal of quality from the UFS can still be of high quality and authentic. Other external laboratories equipped to perform effective authenticity tests may also be used in this respect,” said Prof Kock.

“It is also important to realise that any oil type of quality such as sunflower oil, cottonseed oil, palm oil etc can be used with great success in well controlled frying processes,” he said.

Further discussions will also be held with the Department of Health, the SA National Consumer Union and Agri Inspec to determine priority areas and to develop the most effective low-cost monitoring system.

More information on the UFS oil seal of quality and oil use can be obtained at www.uovs.ac.za/myoilguide

Media release
Issued by: Lacea Loader
Media Representative
Tel: (051) 401-2584
Cell: 083 645 2454
E-mail: loaderl.stg@mail.uovs.ac.za
6 February 2006

Back

Economic and Management Sciences

Education

Health Sciences

The Humanities

Law

Natural and Agricultural Sciences

Theology and Religion

Open Distance Learning

Business School

We use cookies to make interactions with our websites and services easy and meaningful. To better understand how they are used, read more about the UFS cookie policy. By continuing to use this site you are giving us your consent to do this.

Accept