آیا فواید کوچک قابل اغماض هستند؟پیامدهای گسترش سریع خورشیدی سیستم (SHS) در مناطق روستایی بنگلادش برای توسعه پایدار

This paper examines the multiple benefits of the adoption of Solar Home Systems (SHS) and discusses the dissemination potential for sustainable rural livelihoods in developing countries. Based on a household survey conducted in rural Bangladesh, we first identify the impact of SHS on the reduction in energy costs and compare purchasing costs. We then examine household lifestyle changes following the adoption of SHS. Finally, we consider several price-reduction scenarios to examine the potential demand for SHS and to evaluate its future dissemination potential. The results of the analysis indicate that households with SHS successfully reduce their consumption of kerosene and dependency on rechargeable batteries, with the cost reductions accounting for some 20–30% of monthly expenditures on SHS. Moreover, most households with SHS can enjoy its benefits, including electric lighting, watching television, and the ease of mobile phone recharging at home. Further, the price reduction can make possible potential demand in more than 60% of households without SHS, while additional price reductions promote the purchase of even larger SHS packages. This study concludes that even though the scale of single SHS is small, the micro-benefits for each household and the dissemination potential are substantial.

Currently, 1.456 billion people worldwide suffer a deprived supply of electricity, of which 99.8% live in developing countries (IEA, 2009). However, although electricity is a necessity for improving the livelihood of rural households, grid expansion often requires expensive financial investment in infrastructure (power stations, substations, transmission lines, etc.), such as in a developing country like Bangladesh. Grid expansion also implies an increased dependence on fossil fuels and incremental emissions of greenhouse gases (GHG). Accordingly, Solar Home Systems (SHS) based on solar photovoltaic (PV) systems for individual households are becoming more popular in non-electrified areas of developing countries as an affordable alternative for obtaining access to electricity. Unfortunately, the amount of sunshine combined with the relatively small size of SHS at the household level effectively limit electricity generating capacity. Accordingly, as the production of electricity is typically in the range 30–130 Watt peak (Wp), SHS would normally allow households to use only low-powered electrical devices such as electric lamps, radios and cassette players, (black and white) televisions (TV), and mobile phone rechargers. Worldwide solar PV installation for off-grid regions increased up until 2008 (REN21, 2009). SHS projects have also steadily expanded in the developing countries of Asia, South America, and Africa in the last thirty years, especially after the 1990s, with the installation of some 931,700 SHS units in developing countries up until 2000 (Nieuwenhout et al., 2001). While recent figures on the number of SHS units in developing countries are not available, we would expect that the number of installations has continued to increase rapidly as the use of SHS becomes a popular electrification method in developing countries. For example, the rapid growth of demand for SHS can be readily observed in Sri Lanka (Wijayatunga and Attalage, 2005), India (REN21, 2009), and Bangladesh (IDCOL, 2010). The rewards for households with SHS comprise two kinds of benefits, namely savings in energy costs and improvements in lifestyle. First, the installation of SHS can reduce the costs of fuel such as kerosene and paraffin, and allow the removal of the rechargeable batteries relied upon before the installation of SHS (e.g., Wijayatunga and Attalage, 2005 and Mondal, 2010). Second, the contribution of SHS in rural households is also extensive in terms of convenience, improvement in the quality of life, safety, and better quality of lighting from electric as opposed to kerosene lamps (e.g., Martinot et al., 2001 and Urmee et al., 2009). That said, even though the costs of rural electrification with SHS are lower than those of grid expansion, high investment costs for the poor in developing countries usually characterise SHS projects. For instance, a 50-Wp system costs US$490–500 in India and US$480 in Sri Lanka, whereas a 40-Wp system could cost up to US$500 in Vietnam or Cambodia (Urmee and Harries, 2009). 50-Wp systems in Bangladesh cost about US$408 (Grameen Shakti, 2009a). Importantly, households wishing to install SHS must be able to cover most of the upfront cost, irrespective of the nature of the financial support available from donors or non-governmental organisations (NGOs) in the form of loans or grants. On the supply side, there is the prospect of reducing the price of PV modules through reductions in the cost of equipment (van der Zwaan and Rabl, 2004 and Albrecht, 2007). Moreover, the global PV market grows at 30% every year, and this will encourage cost reductions in PV modules (Albrecht, 2007). In fact, the market price of PV modules has been falling over the past twenty years, with prices decreasing at 20% per annum (per Wp) from 1976 to 1996 (van der Zwaan and Rabl, 2004). These evolutional trends will encourage price reductions in SHS. As SHS packages consist of other components, such as batteries and electric lights, in addition to the administrative costs, there will be further potential for price reductions in the future. A question that arises in the context of the promotion of SHS-based rural electrification is whether households that purchase SHS can enjoy tangible benefits commensurate with the high cost of installation. Another question concerns whether it would be possible to boost the demand for SHS through reducing the price of the equipment. As a way forward, this study attempts to estimate the impact of SHS on energy cost reduction by comparing the expenditure on energy with the payments on SHS. If households with SHS can gain substantial benefits, even with the small-scale SHS currently available, the micro-benefits will have a considerable impact on rural society through the increasing use of SHS. The main contributions of this paper are twofold. First, we identify the impact of SHS on the reduction in energy costs, and compare the purchasing costs of SHS. We examine the impact on energy cost reduction by comparing the expenditure on energy with the payments on SHS. If SHS can become a sufficient alternative energy source for the household, then the cost reduction impacts may be enormous. To date, few studies have analysed these cost reduction impacts numerically, with the exception of Wijayatunga and Attalage (2005), who showed that in Sri Lanka expenditure on kerosene decreased to zero for more than 90% of households following installation of SHS. Moreover, earlier studies evaluate the effects of lifestyle changes with a “before and after comparison” (e.g., Acker and Kammen, 1996, Gustavsson and Ellegård, 2004, Urmee and Harries, 2009 and Linguet and Hidair, 2010). A comparison between SHS households and non-SHS households should also provide additional insights into the impact of SHS adoption on the standard of living, hitherto limited to work by Wamukonya and Davis (2001). Second, we examine the dissemination potential of SHS for households without SHS given the price reduction. Unlike the previous literature, we need to assess the potential demand for SHS from the viewpoint of potential users. To do this, our analysis provides some scenarios for SHS price reductions, and obtains the latent demand for SHS of households currently without SHS. This study examines the benefits of adopting SHS and the future dissemination potential of SHS using a household survey conducted in 2009 in rural Bangladesh, a country where rural electrification with SHS has proceeded rapidly. The structure of the paper is as follows. Section 2 describes solar photovoltaics and the diffusion of SHS. Section 3 summarises the case activities of the three regions that field survey conducted for both families with and without SHS. Section 4 details the impact on energy cost reduction and then compares these benefits with the payments associated with the adoption of SHS. Section 5 discusses the lifestyle changes in the households from the viewpoint of the benefits of electric lighting, watching television, and mobile phone recharging. Section 6 illustrates the impact of the declining prices of SHS on the further diffusion of SHS for households currently without SHS. The final section concludes.

This research examines the benefits of adopting SHS and the future dissemination potential of SHS in rural Bangladesh. Given the rapid dissemination of SHS, this research attempts to assess whether the micro-benefits generated by SHS create tangible impacts for rural households, and examines the potential for accelerating the demand for SHS by reducing its price with a price-reduction scenario. By the use of case studies in Bangladesh, this paper attempts to highlight further diffusion scenarios when price reduction of SHS has been achieved. This study found that most households could be free from kerosene and rechargeable batteries, and the reduced costs of those energy sources accounted for 20–30% of the monthly payments on SHS. We confirm that even though households have paid the monthly fee, they can still offset a certain amount. At the same time, the avoidance of kerosene consumption and a reduction in dependence on rechargeable batteries both contributed to reductions in fossil fuel consumption in Bangladesh. This implies that the adoption of SHS also helps reduce GHG emissions at the household level. In addition, this research highlights the lifestyle benefits in terms of the use of electric lights, watching TV, and the recharging of mobile phones. Electric lamps provide a better quality of lighting, which not only improves the indoor air quality but also creates a better environment for studying and working at home. Watching TV provides opportunities for enjoying entertainment programs and understanding updated news. SHS makes mobile phone recharging possible at home for those who previously went outside the home for recharging. Therefore, the benefits are obvious. These findings indicate that even though the scale of single SHS is small, the micro-benefits for households are significant. The dissemination of the benefits of SHS could be further accelerated through price reductions in installation. For instance, a 10% price reduction encouraged 61% of non-SHS households to consider adopting SHS, and a 30% price reduction provided the incentive for 68% of non-SHS households to consider purchasing SHS packages. Further, a price reduction of 30% encouraged not only a decision on purchasing SHS but also a demand shift toward larger packages. The PV module usually accounts for the majority of system capital costs (Byrne et al., 1998 and Stutenbäumer et al., 1999), the price reduction on the SHS packages will be achieved by price reduction in solar panels, and will promote sustainable rural development with solar photovoltaic technologies in Bangladesh. This suggests that further research should attempt to analyse how to mix policy tools with the aim of maximising consumer interest and reducing the price of SHS for further dissemination of the micro-benefits for households.