How does a solar PV-driven hot water system perform in comparison with an equivalently sized solar thermal driven system in the same locality?

Angelo Buckley from University of Stellenbosch recently addressed this in a lecture entitled “Comparison of Photovoltaic and Solar Thermal Hot Water Systems in the South African Context”.

The lecture was based on a paper emanating from a study that was carried out as a financial feasibility analysis using the performance and cost data recorded from a 1.56 kWp PV and 2.4 m² solar thermal hot water systems installed at two separate houses on Mariendahl Farm near Stellenbosch, South Africa. The study was part of the SOLTRAIN programme.

Performance data recorded from these systems was also used to investigate the financial feasibility of another inexpensive PV-waterheating system locally available on the South African market. In his lecture, Angelo Buckley compared the performance and financial feasibility of the 4 different alternatives of solar water heating systems over a 25-year period.

By the end of phase III of the SOLTRAIN programme, 3 000 people had been trained in 110 training courses, and the lessons learned in the courses have been implemented by local companies in 326 demonstration projects. The annual solar yield of all the plants installed since 2009 adds up to 3 533 MWh with CO₂ savings of 1,222 tons.

This was outlined in a lecture delivered by Werner Weiss late last year, which was based on a paper entitled "More than 300 Solar Thermal Systems as a Result of a Training and R&D Co-operation"

The lectures outlined above were delivered at the ISES Solar World Congress held in late 2019 in Santiago, Chile. Karen Kritzinger and Angelo Buckley from Stellenbosch University in South Africa and Werner Weiss from AEE INTEC in Austria were in attendance.

In keeping with some of SOLTRAIN's key focus areas, and specifically the strengthening of institutional structures which can offer expert advice, training and technical support on solar thermal technology, one of SOLTRAIN's South African partners, SANEDI hosted a half day of 'decision makers' seminar on solar water heating  operating at different scales, followed by a half a day site visit to an installation comprising 1 500 litres of storage, heat pump backup and 30m² of solar collector area at a military base in Hoedspruit.  The target audience for this seminar was the military decision makers within the Department of Defence (DoD) as well as the tourism and hospitality service providers from Limpopo province.

Some of the technical topics for the first part of the seminar included:

The second part dealt with the economic and investment aspects and included:

Dr Karen Surridge from SANEDI presented both parts of the seminar using the Hoedspruit installation and its performance as a practical case study for the latter.

In discussion after the presentations, it emerged that the security of supply that solar thermal can provide is what most participants would regard as being their primary driver to invest in solar thermal technologies, specifically in a country that is under the continuous threat from loadshedding.

Since observing the benefit of investing in solar thermal energy, the the DoD has begun plans for further investment and many of the workshop participants indicated that they would be pursuing the same plans of shifting their thermal reliance to the sun rather than electricity. 

One of the SOLTRAIN programme's key focus areas is the strengthening institutional structures which can offer expert advice, training and technical support to the local industry and government officials. To this end, Osona Village Management accepted a proposal from SOLTRAIN, through the Namibian University of Science and Technology - Namibia Energy Institute to train their  housing contractors on quality assurance in the selection and installation of solar water heaters

The main objective of the training was to train the housing developers and contractors on how to design, install and to maintain the thermosiphon solar water heating systems.  Beyond the practical component, training highlights included quality control and an exploration of the future role and potential of solar water heating systems in a sustainable energy supply for Namibia.

The Deputy Minister of the Ministry of Mines and Energy, Honourable Kornelia Shilunga, officially opened the training course. According to Shilunga,  “in order to achieve the goals set out in the Namibian Solar Thermal Roadmap, more collaboration with Housing programmes is required for broad roll-out on small-scale solar water heating systems. It is also essential to have enough skilled experts to be able to design, install and to maintain these solar thermal systems”.

The National University of Science and Technology (NUST), a SOLTRAIN partner in Zimbabwe,  was one of the organisations that exhibited at the 2019 edition of the Water, Sanitation and Energy (WASHen) Conference and Exhibition. The two day event was held at the Zimbabwe International Trade Fair (ZITF) late last year.

NUST was represented by a team from the Industrial and Manufacturing Engineering Department. The main aim of SOLTRAIn activities at the exhibition was to raise awareness of the Solar Thermal Technology Roadmap and Implementation Plan which was signed in July 2019 by the Minister of Energy and Power Development, the Fortune Chasi.