Solar Water Heaters are one of the most simple yet profoundly effective renewable technologies. Their simplicity, however, belies their potential to make a major contribution to the reduction of greenhouse gas emissions as well as stimulate local markets and macroeconomies. Solar water heaters have many benefits, they empower individuals and nations to contribute to environmental protection, save the homeowner money and create employment and skills development. Global concern over a looming energy crisis, water scarcity and man-made climate change are driving a huge demand for clean technologies, which focus on preserving the earth’s resources - energy, water, air and soil. This study examines the potential for widespread diffusion of solar water heaters in Taiwan and South Africa. Diffusion models such as Rogers (1962) and Bass (1969) are utilized to gain insight into what influences the adoption decision and to assess the key factors for widespread diffusion. Barriers and constraints to market expansion are analyzed to determine what strategies could be employed to overcome these barriers. The Payback Period Model (Sidiras & Koukios, 2005) is utilized as a measure of the economic viability and potential for diffusion. The payback period is widely recognized as the key element in the adoption decision.

&Ardente, F., Beccali, G., Cellura, M., & Lo Brano, V. (2005). Life cycle assessment of a solar thermal collector: Sensitivity analysis, energy and environmental balances. Renewable Energy, 30, 109-130.
Balmera, M., Beallb, J., Berglerb, H., Gruppb, M. (2008). An overview of international experience in manufacturing and promotion of solar water heating systems with price comparisons and lessons for South Africa. Energy for Sustainable Development, 11(3), 11-16.
Banks, D., & Schaffler, J. (2006). The potential contribution of renewable energy in South Africa. Sustainable energy and climate change project (SECCP).
Chang, K. C., Lee, T. S., Lin, W. M., & Chung, K. M. (2008). Outlook for solar water heaters in Taiwan. Energy Policy, 36, 66-72.
Chang, K. C., Lin, W. M, Lee, T. S., & Chung, K. M. (2008a). Survey of large-scale solar water heaters installed in Taiwan. Proceedings of ISES World Congress 2007 (Vol. I – Vol. V). Springer: Berlin Heidelberg.
Chang, K. C., Lin, W. M, Lee, T. S., & Chung, K. M. (2008b). Local market of solar water heaters in Taiwan: Review and perspectives. Renewable & Sustainable Energy Reviews, 13(9), 2605-2612.
Chen, F., Lu, S., Wang, C., & Chang, Y. (2008). Promotion strategies for renewable energy in Taiwan. Renewable and Sustainable Energy Reviews, 12, 1681-1691.
Chow, T. T., Fong, K. F., Chan, A. L. S., & Lin, Z. (2006). Potential application of a centralized solar water- heating system for a high-rise residential building in Hong Kong. Applied Energy, 83, 42-54.
Crawford, R., & Treloar, G. (2004). Net energy analysis of solar and conventional hot water systems in Melbourne, Australia. Solar Energy, 76, 159-163.
Davidson, O., & Winkler, H. (2003). South Africa’s energy future: Visions, driving factors and sustainable development indicators. Energy & Development Research Centre, Paper for the Development and Climate Project, Cape Town.
Dodson, J. A., & Muller, E. (1978). Models of new product diffusion through advertising and word-of-mouth. Management Science, 24(15), 1568-1578.
Einav, A. (2005). Solar energy research and development achievements in Israel and their practical significance. Journal of Solar Energy Engineering, 126(3), 921-928.
Houri, A. (2006). Solar water heating in Lebanon: Current status and future prospects. Renewable Energy, 31, 663-675.
Junfeng, L, & Runqing, H. (2005). Solar thermal in China: Overview and perspectives of the Chinese solar thermal market. Refocus, 6(5), 25-27.
Kaldellis, J. K., El-Samani, K., & Koronakis, P. (2005). Feasibility analysis of domestic solar water heating systems in Greece. Renewable Energy, 30, 659-682.
Kalogirou, S. (2003). The potential of solar industrial process heat applications. Applied Energy, 76, 337-361.
Kalogirou, S. (2004) Environmental benefits of domestic solar energy systems. Energy Conversion and Management, 45, 3075-3092.
Kalogirou, S. (2003). The energy subsidization policies of Cyprus and their effect on renewable energy systems economics. Renewable Energy, 28,1711-1728.
Kalogirou, S., & Tripanagnostopoulos, Y. (2006). Hybrid PV/T solar systems for domestic hot water and electricity production. Energy Conversion and Management, 47, 3368-3382.
Karekezi. S, Kimani.J, Wambile. A, (2007). Renewables in Africa Energy Experts’ Concept Paper.
Labay.D, Kinnear T (1981). Exploring the consumer decision process in the adoption of solar energy systems. Journal of Consumer Research, Vol.8, No.3.pp 271-278.
Mahajan, V., Muller, E., & Srivastava, R. (1990). Determination of adopter categories by using innovation diffusion models. Journal of Marketing Research, 27(1), 37-50.
Menanteau, P. (2007). Policy measures to support solar water heating: Information, incentives and regulations.
Milton, S. (2006). Sustainable development of solar water heating systems: An analysis of barriers to technology diffusion and recommendations for policy interventions.
Milton, S., & Kaufman, S. (2005). solar water heating as a climate protection strategy: The role for carbon finance.
Morrison, G. L., Anderson, T., & Behnia, M. (2004). Seasonal performance rating of heat pump water heaters. Solar Energy, 76, 147-152.
Muneer, T., Maubleu, S., & Asif, M. (2006). Prospects of solar water heating for textile industry in Pakistan. Renewable and Sustainable Energy Reviews, 10, 1-23.
Nahar, N. M. (2002). Capital cost and economic viability of thermosyphonic solar water heaters manufactured from alternate materials in India. Renewable Energy, 26, 623-635.
Perlack, B., & Hinds, W. (2003). Evaluation of renewable energy incentives: The Barbados solar water heating experience.
Pillai, R., & Banerjee, R. (2006). Methodology for estimation of potential for solar water heating in a target area. Solar Energy, 81, 162–172.
Reddy, S., & Painuly, J. P. (2004). Diffusion of renewable energy technologies: Barriers and stakeholders perspectives. Renewable Energy, 29, 1431-1447.
Sidiras, D. K., & Koukios, E. G. (2005). The effect of payback time on solar hot water systems diffusion: The case of Greece. Energy Conversion and Management, 46, 269-280.
Smyth, M., Eames, P. C., & Norton, B. (2005). Integrated collector storage solar water heaters. Renewable and Sustainable Energy Reviews, 10, 502-528.
Spalding-Fecher, T. S., & Wamukonya, N. (2002). Residential solar water heating as a potential clean development mechanism project: A South African case study.
Steenblik, R. (2006) Liberalization of trade in renewable energy and associated technologies: Biodiesel, solar thermal and geothermal energy. OECD Trade and Working Paper.
Tiwari, A., & Sodha, M. (2006). Performance evaluation of solar PV/T systems: An experimental validation. Solar Energy, 80, 751-759.
Tsoutsos, T. (2002). Marketing solar thermal technologies: Strategies in Europe, experience in Greece. Renewable Energy, 36, 33-46.
Visagie, E., Prasad, G. (2006). South Africa: Biodiesel and solar water heaters. Energy Research centre. University of Cape Town, South Africa.
Weiss, W., Bergmann, I., & Faninger, G. (Edition 2008). Solar heat worldwide: Markets and contribution to the energy supply 2006.
Winkler, H., Davidson, O., Kenny, A., Prasad, G., Nkomo, J., Sparks, D., Howells, M., & Alfstad, T. (2006). Energy policies for sustainable development in South Africa. Energy Research centre. University of Cape Town, South Africa.
Wu, J. H., & Huang, Y. H. (2006). Renewable energy perspectives and support mechanisms in Taiwan. Renewable Energy, 31, 1718-1732.