Though there has been a renewed interest in solar water heating technologies over the last decade due to concerns about energy prices, energy security and anthropogenically induced climate change, solar water heating is by no means a new technology. The industry is well established with many years of manufacturing and installation experience worldwide as well in South Africa (Weiss et al 2009, Holm 2005).
Figure 30 Historical statistics on SWH shipments in South Africa (Holm 2005, p.26)
Figure 30 presents a graphical illustration68 of the development of the SWH industry in South Africa. Unglazed systems are almost exclusively used for swimming pool heating in the high income market whilst glazed systems are used for domestic water heating (Holm 2005, p.27).
68 Data is not available for the omitted years
From the figure it is clear that SWHs have been installed and manufactured in South Africa since at least 1975 and that initial market uptake, in all likelihood due to the oil crises of the 70s and 80s, was very high. Peak installation for glazed collector systems was attained in 1983 and even with renewed interest installations have not yet recovered to the same levels.
Prasad (2007) divides the development of the SWH industry in South Africa into three historical phases.
• Phase 1 between 1978 and 1983 when there was widespread acceptance of SWH technology and many installations
• Phase 2 between 1984 and 2003 during which there was a large-scale collapse of the SWH market
• Phase 3 commencing after 2003 with increased government support for SWHs as well as renewed interest by middle to high income consumers.
According to Prasad (2007, p.5) and Holm (Holm 2005, p.31) the interest in SWHs from the late 1970s into the early 1980s was largely due to the promotion of solar water heating technology by government through the CSIR due to the energy crisis experienced during that time. The SWH industry grew rapidly in this time and eventually there were six companies that manufactured and installed SWHs for middle to high-income consumers. Peak production was attained in 1983 with 27,000 m2 of solar collector area installed during that year. Unfortunately that was also the year during which government supported awareness raising of SWH was stopped and the market collapsed soon thereafter. By 2004 it had still not regained its former levels69. Holm (2005, p.31) also attributes some of the slump in market demand to an exceptionally cold spate in the Northern parts of South Africa during 1982 which destroyed several thermosyphon SWH systems through frosting. This reduced customer trust in the technology and emphasised the importance of using the appropriate combination of technology for each application. The slump in demand after government support waned indicates that the industry needs some level of market intervention to achieve initial success. External, government intervention was also necessary to encourage the development of SWH markets in other countries such as Israel, Austria, the Barbados, China and Cyprus (Sterman 2009; Sunbelt Solar 2009; C. Meyer 2008, Langniss & Ince 2004). For the low-income market awareness raising alone is unlikely to be enough. The successes of the awareness raising campaign in the 1970s and 1980s were largely in middle - to high income markets (Holm 2005) but it is clear that intervention of some nature is required.
Between 1984 and 2003 the SWH industry remained depressed with little interest from government or mainstream private consumer markets. By 2001 the output of glazed SWHs was still only at 46.8% of the 1983 level (Holm 2005, p.26). Figure 31 shows the estimated cumulative capacity of SWH in South Africa in 2004 based on an estimated average system lifetime of 20 years (Holm 2005, p.22). From the figure it is clear that the total available SWH capacity has actually declined as the systems installed during the boom phase in the 1980s have expired without being replaced by new installations. By 2004 glazed collectors
69 From recent interviews with SWH suppliers it seems that the industry had finally started recovering to its 1980s levels during 2007 and 2008, the recession of 2008/2009 dampened demand somewhat but increased Eskom subsidies and electricity price increases in 2010 have led to increased demand again.
produced an estimate of 300GWh of energy per year at 172 MW capacity, down from a peak production level of more than 350 GWh per year, at a capacity of more than 200MW, in 199770.
Figure 31 Annual energy produced by cumulative active SWH systems in South Africa (Holm 2005, p.30)
2004 heralded a new phase in the development of the SWH industry. There has been renewed support from public authorities, exemplified by the White Paper on Renewable Energy of 2002, identifying solar water heating as a critical part of national government’s renewable energy strategies, and the Eskom SWH rebate scheme. Several local authorities such as the City of Cape Town and Nelson Mandela Bay have also taken the initiative in developing policies to support the rollout of SWHs, mostly in the middle to high income residential market71. It remains to be seen how sustainable and effective the renewed support for the SWH industry will be in the middle to high income residential market but it seems unlikely that current initiatives will be sufficient to achieve the large-scale rollout of SWHs in low-income communities as they are targeted at middle - to high low-income consumers. The technology remains too expensive for low-income markets (Hertzog 2009). To make such a rollout a reality more specific government support will be required.
70 Drawn up with a nominal capacity of 0,7kW/m² of installed capacity, based on international standards developed by the International Energy Agency’s Solar Heating and Cooling Programme (Holm 2005, p.30)
71 For more detailed descriptions of these projects please refer to the document entitled Existing Solar Water Heating Programmes in South Africa on the attached CD