Towards Design of Sustainable Energy Systems in Developing Countries: Centralized and Localized Options

Energy use in developing countries is projected to equal and exceed the demand in developed countries in the next five years. Growing concern about environmental problems, depletion and price fluctuation of fossil fuels pushes the efforts for meeting energy demand in an environmentally friendly and sustainable way. Hence, it is essential to design energy systems consisting of centralized and localized options that generate the optimum energy mix to meet this increasing energy demand in a sustainable manner.;In this study, we try to answer the question, "How can the energy demand in Rampura village be met sustainably?" via two centralized clean coal (CCC) technology and three localized energy technology options analyzed. We perform the analysis of these energy technologies through joint use of donor-side analysis technique emergy analysis (EA) and user-side analysis technique life cycle assessment (LCA). Sustainability of such an energy combination depends on its reliance on renewable inputs rather than nonrenewable or purchased inputs.;CCC technologies are unsustainable energy systems dependent on purchased external inputs almost 100%. However, increased efficiency and significantly lower environmental impacts of CCC technologies can lead to more environmentally benign utilization of coal as an energy source. CCC technologies supply electricity at a lower price compared to the localized energy options investigated.;Localized energy options analyzed include multi-crystalline solar PV, floating drum biogas digester and downdraft biomass gasifier. Solar PV has the lowest water and land use, however, solar electricity has the highest price with a high global warming potential (GWP). Contrary to general opinion, solar electricity is highly non-renewable. Although solar energy is a 100% renewable natural resource, materials utilized in the production of solar panels are mostly non-renewable purchased inputs causing the low renewability of solar electricity.;Best sustainability results are obtained for full capacity operation in anaerobic digestion and for single fuel mode (SFM) operation in biomass gasification. For both of the processes, cost of electricity reduces 2-3 times if they are operated properly. However, there is not enough ipomea to run the biomass gasifier in SFM in Rampura, hence optimum operation scheme is ideal dual fuel mode (DFM) operation for the biomass gasifier analyzed.;Emergy analysis of Rampura village and its subsystems reveal that sustainability is not achieved both at the village and in the subsystems levels since they are highly dependent on non-renewable material and energy inputs. To improve the overall sustainability in Rampura, dependency on purchased inputs fodder, fertilizer and diesel, non-renewable cooking fuel wood should be reduced.;In satisfying energy demand in Rampura, biogas cooking and 70% biogas cooking scenarios perform better than electricity options in all of the objectives considered. Other than minimum land and water use objectives, electricity-RM and electricity-GM scenarios overlap and do not have a significant difference in terms of performance.;Based on these results, the best option to meet the energy demand in Rampura would be to meet all the cooking energy with direct use of biogas. However, 70% biogas cooking scenario may be a more practical option since it both satisfies energy demand in an environmentally benign manner and satisfies the cultural needs of Rampura people.;When 30% of cooking is performed by utilizing improved biomass cook stoves in the traditional way, the biogas potential becomes enough to meet all the remaining energy demand (70% of cooking, lighting and irrigation) in Rampura, hence energy security and reliability are ensured. Furthermore, utilizing biogas for cooking enables more agricultural residues to be available as fodder and eases the pressure on environment due to excessive woody biomass harvesting. Additionally, CH4 emissions from cow dung are avoided via production of biogas while the sanitation improves in the area. The GHG emissions related to cooking with inefficient cook stoves are also significantly mitigated through the use of biogas and improved biomass cook stoves.;Energy demand in developing countries is subject to increase with increasing prosperity and consumerism. This increasing energy demand will necessitate the utilization of centralized energy options even in the rural areas of developing countries in the near future. Utilizing centralized clean coal technologies to meet this demand can ease energy related environmental problems, especially global warming significantly. And, adopting conscious and renewable energy oriented consumption patterns, avoiding consumption beyond the carrying capacity of these regions can contribute to achieve global level sustainability and ease the environmental burdens and problems in the developing countries.