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Hybrid power systems (HPS) based on photovoltaic (PV), diesel generators (DG), and energy storage systems (ESS) are widely used solutions for the energy supply of off-grid or isolated areas. The main hybridizing challenges are reliability, investment and operating costs, and carbon emissions problems. Since HPS are usually sized to provide energy continuously, it is essential to use the solar energy potential close to full capacity, especially on cloudy days. One of the prominent solutions to overcome these challenges is integrating solar tracking systems (STS). This article focuses on the optimal sizing of HPS based on PV-DG-ESS utilizing STS by analyzing technical, economic, and environmental aspects. Optimization is performed with the MILP solved via Gurobi, considering the net present cost (NPC) and loss of power supply probability (LPSP) objectives. The results indicate that horizontal and dual solar trackers can provide up to 50% better energy harvest performance and reduce NPC by up to 7%. It is also found that there is no significant difference in cost reduction between both systems. Moreover, STS is feasible if the cost is less than 375 USD and 250 USD for Sudan and South Sudan, respectively. [ABSTRACT FROM AUTHOR]

The aim of this research is to examine the techno-economic viability of both off-grid and on-grid hybrid renewable energy systems for Jordan's Al-Karak governorate. Hybrid Optimization of Multiple Energy Resources (HOMER) Pro software was used in this article to evaluate the carry feasibility to maximize the renewable energy (RE) integration in hybrid energy systems based on different configurations, grid-connected and stand-alone systems of the wind turbine, biogas plant, photovoltaic (PV) panels, flywheel, and batteries while minimizing the net present cost, the Levelized cost of energy and CO2 emissions mitigation. The results showed that the PV/Wind system, connected to the grid with batteries for storage is the optimal configuration for sustainable Al-Karak governorate electrification whilst achieving environmental benefits and guaranteeing reliable and continuous energy access with the lowest net present cost and the Levelized cost, 298,359 USD$ and 0.024 USD$/kWh respectively, and high RE share, 71.8% of electricity is generated from wind and 28.2% is purchased from the grid and emits 220 tons of CO2 per year, 53% less than a grid alone system. Such a system would provide advantages in terms of energy independence and improved environmental quality. • A hybrid renewable energy system for Jordan's Al Karak governorate was optimized. • Six different scenarios of renewable energy systems were examined. • The impact of the optimal configuration on GHG emission was analyzed. • PV/Wind/batteries system, connected to grid was the optimal configuration. [ABSTRACT FROM AUTHOR]

The study explores the techno-economic feasibility and viability of a Photovoltaic-Diesel Hybrid system for rural electrification in sub-Sahara Africa with a case study of Chilubi island, a remote district without access to electricity in the Northern Province of Zambia. Using HOMER (Hybrid Optimization of Multiple Electric Renewables) Pro software, the best and most feasible technical solutions through different hybrid system configurations, combinations and the district's rate of access to electricity were considered based on the least Levelized Cost of Energy (LCoE) and life cycle costs of the project. The results show that operating diesel generators as stand-alone is not economically sustainable and has a high LCoE. Influencing factors include variability in diesel pump prices, high fuel transportation costs, high cost of operation and maintenance, among other factors of concern. 100% photovoltaic (PV) with a battery system gave the lowest LCoE. However, the initial capital cost of solar energy projects in Zambia is relatively high compared to the equivalent diesel-based plants, as shown herein. It explains why diesel power plants are favoured for off-grid settlements. On the hand, the low operational cost and LCoE of PV power plants favour rural districts as they offset the high initial capital costs. Additionally, the continued downward trend in the cost of PV installations per kWp has opened discussions among policymakers and energy planners in Zambia to favour rural electrification with renewable energy-based power generation. This study contributes to this discussion. • Grid extension is costly for rural electrification in Southern Africa. • Offgrid PV-Diesel generation microgrids are options for cheaper electricity. • Techno-economic analysis herein favours high penetration of PV and storage. • $ 1 increase in fuel increases LCoE by $ 0.283 and vice versa. • PV-hybrids are expensive and may require government interventions to implement. [ABSTRACT FROM AUTHOR]

As global efforts to decarbonise industries continue, there is increasing pressure to identify and proliferate sustainable methods of generating electricity, in-line with the United Nations' Sustainable Development Goal 7. The in-stream water wheel is a pico-hydropower technology that generates electricity using only the kinetic energy in the fluid, rather than both potential and kinetic, like most forms of pico-hydropower. Current methods of estimating the power output of these turbines lack validation, robustness and proper justification for their assumptions. This study has developed a new method for predicting the power output of in-stream water wheels, based on fluid dynamics principles, and has been compared with a range of experimental results to confirm its robustness. The new model identifies novel characteristics of the power stroke of the turbine blade, including unsteady effects and negative torque production at certain blade angles. In addition, the model can be tuned to match experimental data, improving its accuracy in specific applications. The better prediction of power output aims to encourage the use of in-stream water wheels as part of the global decarbonisation strategy. • Pico-hydropower for rural electrification. • Robust analytical prediction of kinetic in-stream water wheels. • Power prediction using fluid mechanics principles. • Greater modelling accuracy compared to existing models in literature. [ABSTRACT FROM AUTHOR]

This research paper focuses on techno-economic modeling and optimal sizing of autonomous hybrid microgrid systems. The optimal configuration of the suggested stand-alone system was performed by developing a size optimization model based on the metaheuristic novel Grasshopper Optimization algorithm (GOA) method to minimize the Total Net Present Cost (TNPC), unmet load, and Cost of Energy (COE) in the Nsukka Community which comprises 88 villages. The GOA and HOMER Pro Software are employed to compare results across four possible configurations of hybrid renewable power systems (HRES). The comparative analysis between GOA and HOMER shows that configuration-4 (biogas/Diesel), emerges as the optimal solution, with a 0 % unmet load at the COE of $0.01783 per kWh. The findings indicated that the GOA-based HRES, with a higher saturation of Biogas and photovoltaics (PV), proves to be more affordable in comparison to the HOMER-based solutions. The reduction in the COE and NPC of renewable energy for peak demands highlights the growing importance of biogas generators as an affordable local power supply to meet energy demands. This underscores the potential of the GOA in optimizing hybrid renewable energy systems for remote communities, producing an economically viable and sustainable energy solution. [ABSTRACT FROM AUTHOR]

Significant increases in renewable energy are needed in electricity systems in order to reduce greenhouse gas emissions, particularly in the face of increasing electricity demand arising from the electrification of heat and transport. Greater flexibility is required in the electricity system to facilitate this, using proven flexibility providers such as batteries and interconnection or new technologies yet to be proven. This paper investigates how the relationship between battery and interconnection development and carbon price can impact carbon dioxide emissions and renewable energy curtailment. The study simulates twenty-eight scenarios and sensitivities using a unit commitment and economic dispatch model of a 2030 European power system that acknowledges that coal will not be fully eliminated from the 2030 generation mix. The results show that interconnection and battery deployment can alleviate renewable energy curtailment by over 2.4 TWh for the basecase, but a high carbon price is critical to ensuring their deployment plays a complementary role in reducing emissions. The paper also examines the impact of batteries and interconnection on solar and wind energy curtailment. It reveals that battery development nearly doubled the solar energy benefits achieved by interconnection development in some cases, while wind energy benefited more from interconnection development. • A high CO 2 price is critical to IC and batteries achieving emissions reductions. • IC can facilitate production of cheaper higher emitting fuels when CO 2 price is low. • Solar energy benefits more from deployment of batteries due to similar timescales. • Diversity of wind profiles can be leveraged with increased interconnection. • Regardless of CO 2 price IC and batteries alleviate renewable energy curtailment. [ABSTRACT FROM AUTHOR]

In recent years, higher penetrations of renewable energy generations helped persuade sustainable energy and environmental targets, although their intermittent and fluctuated nature raised technical challenges. However, hybrid power system can minimize these technical issues by integrating flexible generation capable renewable energy sources like biomass. This study deals with optimizing grid-integrated and stand-alone biomass-based hybrid power system for the energy demand of a rural region containing poultry farms. Besides solar and wind energy, energy storage integration is evaluated regarding overall technical-environmental-economic performance, considering the actual manure potential using HOMER Pro. In addition, sensitivity analyses are performed, considering the estimated load and inflations using an artificial neural network method. Using biomass and solar hybrid options offers more autonomous, environmentally friendly, and economic advantages. Biomass-based hybrid power system with solar energy reduced net present cost by around 12% and increased renewable fraction by 7%, and grid-connected options can provide 88.9% renewable fraction. In addition, the energy storage integration increased renewable fraction by around 10% and reduced excess energy by 16%. The proposed biomass-based hybrid power system achieves cost-effective sizing of solar or wind-based hybrid systems, empowers the reliability of renewable energy and presents good consistency of decarbonization targets. [ABSTRACT FROM AUTHOR]

Sustainable development of the inherently complex nature of the energy sector requires a comprehensive understanding of its components and their dynamic interactions. In this study, we employ a system dynamics approach to examine the impact of renewable energy systems and energy efficiency on the performance of the energy sector, and apply this, as a case study example, to the Australian energy sector. Our results show that improving only 1% of energy efficiency would result in 101k/331k GWh energy productivity (5% and 14% of total energy consumption) and reduce domestic CO 2 emissions by 15.3/50 Mt CO 2 -e (4% and 10% of total domestic emissions) by 2030/2050. Switching to renewable energy for transportation and therefore saving 5% per year of current oil consumption may decrease dependency on oil to half by 2030 and to zero by 2050, and reduce domestic CO 2 emissions by 74.1/198 Mt CO 2 -e (18% and 41% of total domestic emissions). Switching to renewable electricity by 3% annually may lead to 60.8/129 Mt CO 2 -e reduction in domestic CO 2 emissions (15% and 27% of total domestic emissions) by 2030/2050. Electrification of other sectors, mainly the manufacturing sector, increasing the use of renewable energy by 4% annually, may lead to 43.3/106 Mt CO 2 -e reduction in domestic CO 2 emissions (11% and 22% of total domestic emissions) by 2030/2050. Improving energy efficiency, switching to renewable energy for transportation, switching to renewable electricity, electrification of sectors that do not currently run on electricity with the use of renewable energy could achieve zero domestic CO 2 emissions by 2050 while energy consumption stays almost stable (0.5%/year). This process may be accelerated by improving energy efficiency by more than 1%. • Energy efficiency increases energy security and reduces emissions. • Switching to renewable transportation reduces emissions and cuts oil dependency. • Switching to renewable electricity is crucial for reducing domestic CO 2 emissions. • Electrification of all sectors using RE is possible. • Synergy between energy efficiency and RE is crucial for a sustainable energy future. [ABSTRACT FROM AUTHOR]

The recent persistent power interruption in Nigeria has significantly disrupted commercial activities, resulting in a magnificent economic loss, supply chain ripples and revenue loss. As a result, harnessing renewable energy sources to generate electricity has become a popular choice for satisfying ever-increasing load demand and reducing apprehensions on global warming and reliance on depleted fossil fuels. The goal of this research is to determine whether powering a remote community with a hybrid energy system (HES) is technologically, financially and environmentally viable. The optimum design of a standalone HES with the diesel generator (DG), photovoltaic (PV) and battery storage system (BSS) is provided in this study to satisfy the electrical power needs of a farm settlement in Kura, Nigeria by considering generation constraints and load demand. This research work presents a genetic algorithm (GA) to minimize wearing cost of the system (WCS), minimize the land needed for the installation of the DG and PV system, minimize the total annual cost of the system (TAC) and maximize the benefit to cost ratio and revenue from electricity consumption. The findings of the research showed that PV/BSS/DG system is a prospective solution to satisfy the load requirements with least TAC of 67374 $/yr, annual maintenance cost (AMC) of 2808.2 $/yr, annual fuel cost (AFC) of 32300 $/yr and annual emission cost (AEC) of 774.2023 $/yr. The outcomes of the study show that a considerable TAC, AMC, AFC and AEC savings of 26766 $/yr (28.43 %), 2808.2 $/yr (53.09 %), 32300 $/yr (25.4 %) and 774.2023 $/yr (60.69 %) are recorded when compared with using DG alone. The control approach applied in this study has reduced the operational capacity of the DG and prevented about 41157 kg/yr, 419.19 kg/yr and 22.52 kg/yr of CO 2, NOx and SO 2 emissions from being injected into the atmosphere. The simulation outcomes of the research demonstrate that the developed model can significantly reduce cost of electricity in rural communities with the application of HES. Hence, a 45.36 % cost of energy saving has been accomplished through the energy management system introduced in the proposed HES. The study's outcomes can be used as benchmarks to help many countries to enhance access to electricity, raise their living standards and stimulate economic growth. The application of the proposed HES in remote communities can result in greater economic and environmental benefits to a general population of rural dwellers. The findings of the research work are beneficial to designers, independent power providers, investors, researchers and electricity consumers that are looking for a feasible power solution. [ABSTRACT FROM AUTHOR]

Off-grid photovoltaic energy systems (PESs) are increasingly being used for the electrification of remote areas in Brazil, owing to the need for carbon emission avoidance, potential approval of solar resources, and cost-effective expansion limits for conventional distribution systems. However, the complex environment, social, economic, and geographical aspects turn the operation and maintenance (O&M) of PES into a logistic and technical challenge in remote areas. Therefore, this study presents an O&M plan for rural electrification of the Pantanal of the Mato Grosso do Sul (MS) region in Brazil. A quasi-dynamic heuristic approach is proposed, which considers not only the PES requirements but also the environmental constraints, given by the consumer locations, the flood period variation, and the different logistical strategies for off-road assessment. The quasi-dynamic O&M plan was designed based on space, time, and costs, with five main goals: task scheduling, transport route planning, team dispatch, inventory, and vehicle estimation. [Display omitted] • A well based framework is needed to overcome the challenges of rural electrification. • Pantanal MS is a large remote area with very low population density. • To entrust preventive maintenance to local residents attenuates logistic challenges. • Battery life cycle has a major impact on Levelized Cost of Energy. [ABSTRACT FROM AUTHOR]

Access to electricity is vital in rural regions of Africa. There is substantial potential to utilise wind energy, yet investment in renewable energy projects is trivial because it has been insufficiently endorsed. As a result, most people living in remote regions of Africa rely entirely on diesel-powered generators, which expel pollutants in substantial amounts. These adversely affect the health of people and the environment. Sudan – one of Africa's largest countries – has a range of resources from which renewable energy could be generated, including favourable wind power generating conditions. This paper represents the first effort in literature to use a strategic perspective to explore how viable wind energy systems are in Sudan. It reports a study using the Hybrid Optimization Model for Electric Renewables (HOMER) across 21 diverse sites in Sudan. It identifies the optimal wind turbine system and best locations and analyses the costs involved and how much pollution could be prevented by implementing wind farms instead of diesel systems. The results establish that the optimal type of wind turbine across the investigated locations is the Enercon E−138 EP3. Wind farm use is expected to avoid almost 49 million kg/year of pollutants and reduce energy cost by US$0.91317/kWh. The optimal sites for utilising wind energy were Wawa, Dongola, Karima, Wadi Halfa and Al-Goled in order of suitability and their low costs of electricity and high wind speed records. Wind turbine pricing is predicted to reduce over time, so the study varied the cost of wind turbines to understand the impact on project economics. A reduction in wind turbine costs by 10 % lowered energy cost to between US$0.03681/kWh and US$0.04052/kWh. A further 25 % price drop reduced the cost of energy to between US$0.03067/kWh and US$0.03376/kWh. This study reveals the significant potential of integrating renewable energy into the energy mix of Sudan and provides an essential reference for wind farms in the energy sector across other developing countries. • Finding the ideal wind turbine system and sites for exploiting wind energy in Sudan. • Exploring the costs and evaded emissions using wind farms over diesel generators. • Investigating the impact of wind turbine price on the project economics. • The optimal wind turbine was determined to be Enercon E−138 EP3. • The best locations for harvesting wind energy are Wawa Dongola, Karima and Wadi Halfa. [ABSTRACT FROM AUTHOR]

Worldwide, the emerging trend of hybrid renewable energy sources integration in modern power systems is increasing due to privileged prices and clean electricity supply. However, the optimal planning of rural hybrid systems is a challenging and complex task, especially when different alternatives and sustainability aspects are considered. This paper develops an integrated decision-making approach for the optimal planning of a 100% renewable energy supply system comprising solar, wind, hydro, and biomass sources in a rural area located in Pakistan. An hourly-based design optimization analysis of twelve on/off-grid electrification alternatives is performed. The optimization model simultaneously addresses five sustainability criteria related to economy, reliability, ecology, society, and topography aspects. Furthermore, a novel hybrid decision-making model has developed to identify the unique best configuration with on-grid and off-grid options. The proposed model combines fuzzy analytic hierarchy process, multi-objective optimization based on ratio analysis technique for order of preference by similarity to an ideal solution, and evaluation based on distance from average solution methods. The results reveal that the solar-hydro-biomass battery with a life cycle cost of 10.9 M$ is the top-ranking off-grid system. When the hybrid system is connected to the grid, the solar-hydro-battery has found the most appropriate design with a life cycle cost of 12.96 M$. Both scenarios have a negligible capacity shortage of 0.09%. Ecologically, the optimal off-grid system produces only 408.37 kg/yr of CO 2 due to the significant energy share of solar and hydro sources (99.3%). The optimal on-grid system produced the minimum CO 2 with 29,177.89 kg/yr compared to other alternatives. Also, employing the optimal on/off-grid designs require land area and jobs of 96.6 m2, 14 jobs, and 118 m2, 15 jobs, respectively. Overall, the developed approach with the presented case study offers a valuable benchmark and guidelines for investors and stakeholders to create realistic investment plans for the energy industry looking to push efficient inducements to encourage the high dissemination of renewables. [Display omitted] • 100% renewable energy system is established for on/off grid rural electrification. • Twelve distinctive solar/wind/hydro/biomass-based hybrid energy alternatives are optimized. • An integrated fuzzy-AHP/TOPSIS/EDAS/MOORA decision-making model is proposed. • Cost, reliability, emission, social, and topographical criteria are simultaneously considered. • Results prove the long-term sustainability of 100% renewable in rural Pakistan. [ABSTRACT FROM AUTHOR]

The problem of providing electricity to rural sectors in developing countries has been approached by using a variety of strategies, with varying degrees of success. Governments with determination and resources have implemented a utility-led model to pursue or achieve rural electrification. In countries with fewer resources, Governments have opted for the concession-led model, in which rural areas are divided into zones or concession areas and offered to private companies for the provision of electricity. In developing countries, the concession-led model for the electrification of rural areas faces the serious hurdles of the abject poverty of farmers in many rural communities and the large number of small sized villages or highly dispersed settlements. This is the case of Senegal, which adopted the concession-led model, resulting in a rural electrification rate still under 40%. The current study first provides a detailed analysis of the challenges and achievements of the rural electrification program in Senegal. Secondly, we present our model for the creation of universal access to electricity, using the example of a pilot project in Coure Matar, a small village in Senegal. Our model is suitable for small villages, demonstrating the potential generation of job opportunities for small sized companies and the opportunity to achieve 100% rural electrification at a fraction (less than 16%) of the cost of the Senegalese Government's initial estimates to provide just 50% of rural electrification. In this study, the pilot project puts forth a model that could make the realization of universal access to basic electric services in rural areas, even in the poorest countries of the world, a reality. • We present the rural electrification models in developing countries. • We analyze different factors that can impact rural electrification policies. • We present the agency-led policy in Senegal and its structural limits. • We compare policies in Morocco, Senegal, and ECOWAS. • We present a model for universal access to electricity. [ABSTRACT FROM AUTHOR]

The need for energy in rural and remote areas is increasing, and it is exacerbated in developing countries. The wellbeing of communities and citizens depends on access to clean electricity to improve quality of life. An uninterrupted supply of electricity is one of the sustainable development goals (SDGs) that has highlighted the needs and challenges in remote areas. The complexity of designing strategies and solutions is further augmented for villages located in protected areas, national parks, and wildlife refuges, the conservation of which is fundamental to achieving climate, environmental, and ecologic objectives. Fossil fuel-based electricity generation and large-scale transmission networks pose a potential threat to the achievement of SDGs in such areas. This research investigated the use of solar photovoltaic (PV) technology as a renewable energy source (RES) that can cover energy needs of rural areas in a continuous, secure, and sustainable manner. In this study, the feasibility of using solar energy to electrify remote settlements located in protected areas of Iran (Khorasan-e-Razavi) was evaluated using a multi-criteria, GIS-based methodology. A set of criteria was selected to evaluate the suitability of solar PV, including solar irradiance and duration, aspect, temperature, precipitation, and humidity as well as proximity to faults, roads, and rivers. Using the best worth method (BWM), the relative weight of the selected criteria was calculated. The results showed that almost 2% of the region's area is very highly suitable and another 23.5% is highly suitable. This 25% represents an area of 1500 km2 and includes 63 villages. Evaluation of census data showed that available building areas can cover the villages' residential demand using rooftop PV systems. Nonetheless, local and national government support is necessary to develop an effective strategy that results in successful implementation. • A fuzzy approach was used to evaluate influential factors of solar photovoltaic (PV) deployment. • The Best-Worth Method (BWM) was employed to calculate the relative weights of selected factors. • Build-up areas can cover villages' residential demand using rooftop PV systems. • Integrating GIS and BWM proved to be an effective technique to create suitability maps. [ABSTRACT FROM AUTHOR]

The combined operation of renewable energy and pumped storage unit (PSU) has become an important researching tendency in rural electrification, for handling the variable characteristics of power as well as load demand, particularly in standalone applications. Recently, adjustable-speed pumped storage unit (ASU) has been developed as an evolutionary version of fixed-speed pumped storage unit (FSU) due to its adjustable power in pumping mode, larger output range and higher efficiency in generating mode, but presents an increased capital outlay in terms of equipment. Therefore, it is a meaningful topic to appraise the economic benefit of using ASU as energy storage device for the hybrid system, which has rarely been studied quantitatively. In this paper, a scheduling model composed of a photovoltaic generator, a wind turbine, a diesel generator and a PSU, is presented and the technical features of two different PSUs are analysed. The main purpose of the proposed model is to highlight the potential of the ASU to reduce the operation cost for the developed hybrid system. The simulations have been carried out using Cplex called by Matlab. Two scenarios are investigated, including a summer and a winter case. The results show that using the ASU for the developed hybrid system, 46.7% fuel can be saved on a summer day and 11.24% fuel saving can be achieved on a winter day compared to the case where the FSU is used as the energy storage device. [ABSTRACT FROM AUTHOR]

Hydrokinetic energy conversion refers to the conversion of kinetic energy in moving water to electricity. It offers an alternative to conventional hydropower, with benefits of modularity and scalability, in addition to being environmentally and socially less impactful. This study aims to determine the theoretical global riverine hydrokinetic resource. We use a 35 year modelled daily discharge data set and vectorised representation of rivers, with near-global coverage and suitable spatiotemporal resolution, to determine the mean annual energy yield of 2.94 million river reaches. The mean global resource (excluding Greenland) is estimated to be 58 400 ± 109 TWh yr−1 (6.660 ± 0.012 TW). Consideration of global spatial distribution, by river reach, illustrates regional variation and shows a tendency for potential to be concentrated along major rivers and in areas of significant elevation change. China, Russia and Brazil are found to be the countries with the greatest potential. After normalisation by total river length, Bhutan, Nepal and Tajikistan also show great potential. Hydrokinetic energy conversion can benefit isolated communities currently without access to electricity. We consider how the specific advantages of this particular technology have the potential to be combined with and complement other established forms of renewable energy technology, providing the means to support the reduction of energy poverty. • Method developed for global riverine hydrokinetic resource assessment. • Theoretical global riverine hydrokinetic resource estimated to be 58000 TWh/yr. • Mean power of global rivers over the period 1979–2013 estimated to be 6.7 TW. • China, Russia, Brazil, Bhutan, Nepal and Tajikistan offer great potential. • Hydrokinetic energy conversion can benefit isolated communities in energy poverty. [ABSTRACT FROM AUTHOR]

Off grid electrification is key to achieving universal electricity access. Despite the potential of biomass gasifiers as a clean technology to ensure reliable systems, they are not as well looked upon as their advantages suggest. In particular, the software HOMER, which researchers and technicians use the most to simulate and design Microgrids, does not include biomass gasification among its simulation technologies. Although some authors did simulate biomass gasifiers in HOMER, the necessary parameters and procedures to calculate and include them in the tool remain unclear, non-replicable, and leave open research questions as regards modelling. Using the inbuilt Biogas power plant modules in HOMER, this paper presents a set of steps to include the technical and economic parameters to simulate fuelling an electric generator through the syngas produced in a downdraft biomass gasification plant. Two case studies of isolated rural communities in Honduras and Zambia show the viability of the procedure. These case studies also confirm the technical and economic viability of islanded biomass-photovoltaic hybrid renewable energy microgrids. In both cases, the energy demand supplied and distributed by the microgrid had a Levelized Cost of Energy lower than the alternative of extending the electric grid to the communities. • HOMER can model modify gasifiers with the presented methodology. • Technical and economic parameters need to be edited. • Two case studies of rural communities in Honduras and Zambia. • Dry biomass and agricultural waste are the main energy sources of most rural areas. • Gasifiers help to optimise HRES. [ABSTRACT FROM AUTHOR]

Access to electricity has been linked to improved livelihood, education, health, economic growth and overall poverty reduction. Yet, most people living without electricity or with unreliable electricity access are in Sub-Saharan Africa and South Asia. Whilst the largest economy in Africa, Nigeria suffers from severe power outages, forcing many residents to seek self-generation options. By far the most adopted option has been diesel generators which have a relatively low initial investment cost but carry health and environmental risks. Solar photovoltaic systems are a viable alternative, but the higher initial investment is a barrier for many Nigerians. This paper addresses making cleaner electricity through solar PV more attainable, increasing access to more reliable power, and reducing or eliminating the use of diesel generators. It proposes a pathway for securing residential solar PV systems at no additional cost through fuel savings and effective policy. Leveraging real data from a monitoring campaign in Lagos, the commercial hub of Nigeria, results show an opportunity to reduce or eliminate the use of diesel generators. Furthermore, financial analysis of the home solar PV option shows a cost savings of 60–65% over the project life compared to the traditional use of diesel generators for backup power generation. • Solar PV can greatly reduce or eliminate the use of diesel generators in Nigeria. • Financing based on fuel savings is a practical and implementable approach. • Replacing diesel generators with solar PV leads to savings as high as 65%. • Effective government policy is key to the adoption and diffusion of solar PV. [ABSTRACT FROM AUTHOR]

This study aims to design a renewable energy system that can meet the desired electrical load of households with low energy cost, high renewable energy fraction and low CO 2 emissions. Photovoltaic solar power systems used to electrify typical households in Iraq were investigated through simulation and optimisation. One-minute resolution simulations and optimisations were performed to determine the performance and net present cost of two photovoltaic power system configurations, namely (i) off-grid and (ii) on-grid solar photovoltaic power systems. Results show that the two systems exhibit excellent performance, but the on-grid photovoltaic power system requires cheaper cost compared with the off-grid photovoltaic power system. The total energy generated from the off-grid photovoltaic power system meets the desired electrical load of households and recharges the batteries, whereas the excess electricity from the on-grid photovoltaic power system feeds the grid. The two designed systems are environmentally friendly and economically viable. The total net present cost of the off-grid solution is $6,244, and its energy cost is $0.196/kWh. By contrast, the total net present cost of the on-grid system is $6,115, with energy cost equal to $0.183/kWh. The obtained results confirm the suitability of photovoltaic power systems for electrifying single households in addition to feeding the national grid. • Photovoltaic power system for household application. • Simulation-based economic optimisation approach. • Local weather resources highly influence on the optimal design. • Established optimal Off/On grid photovoltaic systems configurations. • Promising solution to decrease CO 2 emissions. [ABSTRACT FROM AUTHOR]

Millions of Solar Home Systems (SHSs) have been progressively installed in rural areas of developing regions, usually in isolated locations that lacked access to electricity, clean water and/or sanitation. Monitoring has been identified as a one of the factors that contribute in rural electrification program success due to these actions increase the system lifetime and reduce the failure of operation of the PV system, improving confident level of the users on the system. This work focuses on the study of the current challenges for the mass scale SHSs monitoring in developing countries, highlighting the weaknesses and the strengths of the applicable methods available. Monitoring systems applicable to SHSs are reviewed, including conventional dataloggers and the novel attempts that apply new technologies based on open source tools and the Internet of Things (IoT). Sensor distributions applicable to SHS monitoring have been reviewed. Main shortcomings related to conventional monitoring systems such as the elevated cost or the dependency on external hardware have been identified, issues that hinder their application of the mass-scale monitoring. Low-cost IoT-based monitoring systems are reviewed and presented as a potential solution to the mass-scale monitoring of SHSs. • Millions of Solar Home Systems (SHSs) were installed in developing regions. • Monitoring of SHSs is a key factor in rural electrification program success. • The integration of IoT allows to monitor SHSs remotely. [ABSTRACT FROM AUTHOR]

Electrification of remote zones is often characterized by high energy costs as a result of the fossil fuels supply and cost associated to its logistic. This study performs a theoretical model and optimization of an ocean thermal energy conversion (OTEC) system coupled to an organic Rankine cycle (ORC) generator for small scale applications in the San Blas archipelago (Panama). The gross electric power has been previously set at 125 kW for the eleven working fluids selected: ammonia, R152a, R1234yf, R1234ze, R125, R134a, R161, propane, isobutene, RE143a and decafluorobutane. Results show R1234yf gets the maximum thermodynamic and net electric efficiency (3.60% and 2.57%, respectively). Ammonia reaches the maximum net electric power (99.3 kW) and, thus, the lowest pumping losses (20.59% of the gross). Besides, despite decafluorobutane shows slightly lower electric power (98 kW) and efficiencies, this fluid does not present environmental hazardous features. Sensitivity analyses show that all performance parameters of the plant are strongly affected by deep and surface seawater temperature variation. Finally, for a surface seawater temperature of 30 °C and deep 5 °C, the net electric power reached is 94.6 kW for R1234yf, 99.3 kW for ammonia and 98.0 kW for decafluorobutane. The net electric efficiency is 2.57%, 2.53% and 2.42%, and the total area required by the heat exchangers is 890 m2, 940 m2 and 986 m2, respectively. • Theoretical model of a small-scale ocean thermal energy conversion system. • R1234yf presents the maximum electric and thermodynamic efficiency. • Ammonia reaches the maximum electric power generation and lowest pumping losses. • The performance parameters strongly depend on seawater temperature changes. [ABSTRACT FROM AUTHOR]

About 84% of the population in Niger live in rural areas and only about 8% of them have access to electricity. For rural population, renewable energy use is an expensive option. This paper seeks to answer the question: Can collaborative consumption and community ownership increase the willingness to pay for the electricity generated through solar photovoltaics (PV) systems among the villagers of a rural area in Niger? Surveys were conducted in a rural village in Niger to assess the WTP for electricity services. These results were compared to the costs of off-grid electrification systems considering collaborative consumption and community ownership approaches. This was done by assessing the willingness to pay through household surveys and comparing the results to different electrification systems under the mentioned concepts. A reduction of about 80% monthly expenses could be achieved by using both collaborative consumption and community ownership. This translates to a possible increase in the WTP from 17% to 81% of the villagers for solar PV based electrification systems. Collaborative consumption, provided its acceptance and equipped with the proper policies and regulations, can thus contribute to a wider access to electricity in the rural areas of the country. • For a case study site in Niger, a field research combined with survey was carried out. • Novel approach of collaborative consumption and ownership model was applied. • A possible reduction of about 80% of the monthly energy costs can be achieved. • The WTP in collaborative consumption operational model increased from 17% to 81%. • Through demand side management, off grid renewables can be accommodated. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyze and compare efficiently of 10 (ten) numerical methods namely, the empirical method of Justus (EMJ), the empirical method of Lysen (EML), the method of moments (MoM), the graphical method (GM), the Mabchour's method (MMab), the energy pattern factor method (EPFM), the maximum likelihood method (MLM), the modified maximum likelihood method (MMLM), the equivalent energy method (EEM), and the alternative maximum likelihood method (AMLM) in order to estimate Weibull parameters for wind energy potential. They were performed by using wind speed data collected in the meteorological station of Bafoussam city, in the west region of Cameroon, in the period from 2007 to 2013. The results of this study obtained from statistical analysis show that the MLM presents relatively more excellent ability throughout the simulation tests, followed by EEM, EPFM and EMJ respectively. They also demonstrated that EEM presented minimum error in estimating the monthly wind power density and that the wind potential of Bafoussam city can be interesting for some applications such as rural electrification and water pumping in agriculture. • Ten methods to assess the effectiveness in determining the Weibull distribution. • The wind speed data was collected in Bafoussam city, Cameroon from 2007 to 2013. • The maximum likelihood method presents more accurate results in the estimation. • The equivalent energy method gives minimum error for monthly wind power density. • Wind potential of Bafoussam, suitable for rural electrification and water pumping. [ABSTRACT FROM AUTHOR]

Eighty per cent of the people without access to electricity live in rural areas. Due to high investment costs in the grid, the solution to providing electricity to these people will mainly rely on the installation of islanded hybrid microgrids. Designers need to consider a variety of factors for the optimal design of hybrid microgrids. However, many of these criteria are qualitative or uncertain. This paper provides a novel methodology to assess the influence of such criteria in the design of a Hybrid Microgrid of Renewable Energy Sources (HRES). The method combines context analysis, literature review and the Analytic Network Process (ANP) through panels of experts and surveys. The methodology ranked the criteria and helped to design a HRES in an isolated Honduran rural community in the Mesoamerican Dry Corridor. The study presents a review and classification of the main criteria and energy technologies considered for the design of HRESs in rural communities. The most influential factors turned out to be the institutional support, the possible expansion of the grid to the community and the availability of local energy resources. Regarding energy technologies, photovoltaic and wind power ranked as the preferred followed by a biomass gasifier as backup. • Access to electricity will largely depend on new microgrids. • The article presents a novel methodology to select energy technologies of a HRES. • Institutional support largely affects the design of hybrid microgrids. • Solar PV is the preferred energy technology for a microgrid in Honduras. [ABSTRACT FROM AUTHOR]

Renewable energy resources and technologies, especially solar thermal and photovoltaic systems, can provide advantageous and clean options for meeting electrical demands. The location and sizing of photovoltaic systems affect the system losses significantly. Here, a new hybrid framework for the optimal location and size for an off-grid solar/hydrogen energy system is proposed using an improved heuristic approach: improved harmony search and geographic information system (GIS). To determine the appropriate capacity and location for a grid-independent photovoltaic scheme in rural areas, a GIS module is used subject to several criteria: social, economic, technical, and environmental. The life cycle cost, the main objective function, is minimized and employed to assess the viability of the stand-alone photovoltaic scheme with hydrogen storage accounting for the reliability of the scheme. The system reliability is measured with the parameter loss of power supply probability. The proposed framework is useful, and is applied here to an actual case study in Iran for illustrative purposes. To validate the effectiveness of the proposed algorithm, the results obtained by proposed algorithm are compared with those of harmony search algorithm-based geographic information systems. The results of the simulation show the advantages of utilizing the proposed framework, based on improved harmony search and geographic information systems, for a grid-independent photovoltaic scheme considering both power quality and cost in remote and island areas. • A hybrid framework is developed for the optimal size and location for a grid-independent solar/hydrogen scheme. • A GIS module is presented for optimal sites for off-grid PV systems. • An improved heuristic approach is developed for size optimization. • Results are compared for the improved harmony search and the harmony search algorithms. [ABSTRACT FROM AUTHOR]

Based on the survey data onto rural households in China, taking biogas produced by crop residues as an example, this paper analyzed rural households' perceived value of energy utilization of crop residues. Then, "interpersonal trust" and "institutional trust" variables are introduced to improve Zeithaml's perceived value model to explore the key factors influencing rural households' perceived value of energy utilization of crop residues. The results show that although the value of energy utilization of crop residues has been recognized by most rural households, there is still some room for improvement. We believe that strengthening the technical service level and creating an atmosphere of mutual trust in rural society will help to improve rural households' perceived value of energy utilization of crop residues. This paper demonstrates the feasibility of the improved perceived value model as a powerful method for better prediction of human psychological perception, and our findings have significant policy implications given that the government can take measures to improve rural households' perceived value to make energy utilization of crop residues more competitive, thus hastening its deployment. • The value of energy utilization of crop straw was recognized by most households. • Most households are eager to realize the agricultural ecological function. • Trust has an impact on households' perceived value. • The improved perceived value model is more powerful than the original one. [ABSTRACT FROM AUTHOR]

As the costs of solar PV continuously decrease and pollution legislation imposes less burning of agricultural residues, decentralized renewable energy is increasingly affordable for providing electricity to one billion people lacking access to a power grid. This paper presents a techno-economic feasibility case study of biomass gasification in off-grid and grid-connected mini-grids for community-scale energy application in rural Uttar Pradesh, India. Energy demand data was collected through surveys in a village with irrigation and agro-processing loads and off-grid households and used to construct a seasonal load profile based on statistical methods. This was used to simulate single-source and hybrid mini-grids based on solar PV, biomass gasification and diesel generation using HOMER Pro. Hybrid PV-biomass or PV-diesel systems were found to offer the highest reliability for off-grid power at the lowest cost. Single-source PV was cheaper than biomass gasification, though the cost of electricity is highly sensitive to biomass supply and gasifier maintenance. Both renewable options were around half the cost of diesel generation. The findings held across grid-connected systems with weak, moderate and strong reliability of grid supply. This suggests that biomass gasification-based mini-grids are not cost-competitive with PV unless the two generation sources are combined in a hybrid system, though they require operational testing prior to implementation. Image 1 • Hybrid PV–biomass or PV–diesel systems offer higher reliability at lower cost. • PV is cheaper than biomass gasification mini-grids for productive energy provision. • Grid-connected PV offers lowest LCOE over 20 years for strong and weak grid supply. • LCOE of biomass systems is highly sensitive to biomass requirement and maintenance. • PV–biomass systems appear resilient to operating parameters but lack field testing. [ABSTRACT FROM AUTHOR]

We propose optimization strategies for cooperating households equipped with renewable energy assets and storage devices. We consider two system configurations: In the first configuration, households share access to an energy farm, where electricity is generated from renewable sources and stored in battery banks. In the second configuration, households are equipped with their own renewable energy sources and storage devices, and are allowed to share energy through the grid. The developed optimization model takes into account location and time-varying energy prices as well as energy transfer fees. To design our strategies, we first establish performance bounds, and compare the two configurations in terms of achievable savings and usability of renewable energy. Then, we devise real-time energy management algorithms by incorporating forecasting techniques in the proposed framework. Simulation results show that the proposed strategies outperform existing solutions by up to 10%. It is also shown that cooperative strategies outperform greedy approaches by up to 6.8%. • Distributed generation outperforms centralized generation due to spatial diversity. • Cooperative energy management outperforms greedy approaches by up to 6.8%. • Proposed real-time optimization outperforms existing solutions by up to 10%. • Proposed real-time optimization handles forecasting errors of up to 50%. [ABSTRACT FROM AUTHOR]

The hybridization of hydrogen and solar energy technologies is an interesting option to satisfy power demands in locations that are isolated from the electric grid. The main advantage of the photovoltaic (PV)-H 2 hybrid system is the possibility of power storage by means of an electrolyzer (EL) which transforms the electricity into hydrogen (H 2). The work described here concerns a methodology to design PV-H 2 hybrid systems that considers the weather data and the electrical variables of the components to perform energy balances and to assess the system in terms of the load requirements, the levels of energy stored and the resulting costs. Two electrolytic systems (water splitting and ethanol electrochemical reforming) were studied in an attempt to find a best trade-off between the size and voltages of ELs. Ethanol reduced the energy requirements of EL at the expense of reagent consumption and lower current density. The energy supplied by these systems costs 0.28 €/kWh (i.e., roughly the same as power prices paid by domestic customers in Spain), but they have the merit of being autonomous and hydrogen has the capacity for seasonal energy storage ‒ thus avoiding electrification constraints in off-grid locations and limitations of short-term electrical energy storages. Image 1 • A novel model for PV-electrolyzer direct coupling is presented, used and discussed. • Two systems (water splitting and ethanol electrochemical reforming) are compared. • The energy supplied costs roughly the same as power prices paid by grid customers. • The systems have the merit of autonomy and capacity for seasonal energy storage. [ABSTRACT FROM AUTHOR]

The present research work is an attempt to develop a dedicated biogas fuelled SI engine technology from a 100 cc motor cycle. Such a small engine is coupled with alternator especially suitable in remote rural electrification which is still not connected to grid line or has a limited access. The experimental work presents the performance results of a small 98 cc, single-cylinder, four stroke cycle gasoline engine which is optimized to run on scrubbed biogas (CH4 93.8%) and raw biogas (CH4 56.6%) with successive modifications to the engine and its components. The work is carried out in stages to develop a dedicated biogas engine technology. The various aspects like piston crown geometry and compression ratio (CR), is investigated in this research work to evaluate the performances using biogas as fuel and comparing the same with gasoline is also made with the results obtained during experimental tests. The tests were conducted at 3000 rpm using three pistons having different crown geometries and cleavage on its crown. The selected three pistons enable to study the significance of CR (in the range of 6–9) and piston crown geometry to achieve the optimal configuration. The experimental results have revealed that increase in CR in a close range of 8:1 with larger cleavage on piston crown geometry enhances engine performance for Biogas fuelled small S.I. engine 100 cc category. It has been observed during comparative analysis that the maximum power produced by the biogas fuelled engine has improved by 13.4%, BSEC has increased by 23.30% and there is an 18.18% improvement in BSFC. • Biogas fuel was tested in a 98 cc petrol engine at various compression ratios. • Piston geometry effects on biogas fuelled petrol engine were examined experimentally. • Large cleavage piston increases the performance of biogas fuelled petrol engine. • Increase in compression ratio improves the performance of biogas fuelled petrol engine. [ABSTRACT FROM AUTHOR]

The present study performs an analysis of the Strengths, Weaknesses, Opportunities, and Threats (SWOT) as a reference point that diagnoses the feasibility of current status and future roadmap to nurture the renewable energy sector in Pakistan. The results identify the social, economic and environmental impacts on the sustainable development of the renewable energy sector through explicit and categorical investigation of strengths, weaknesses, opportunities, and threats in local perspective. Hence, strengths of the renewable sector in terms of available renewable energy potential, validated resource maps, environment friendliness, and the growing private investors are explored, whereas inefficient technologies, huge capital investment, immature institutional framework, and technology-related environmental hazards are found to be the internal weaknesses that need to be fixed. Main opportunities that are found mandatory to be capitalized for the sustainable development are: untapped potential, micro and mini-installations, off-grid energy systems and efficiency improvements, whereas associated threats to be defended for the sustainability of the renewable energy sector are: policy implications, lack of grid connection, and the competitive energy resources. Furthermore, to cope with the energy crisis under the current scenario, policy-based strategies are suggested to ensure the retainability of the renewable energy sector towards secure and sustainable Pakistan. • A survey of the renewable energy sector of Pakistan is presented. • Strengths of the renewable energy sector of Pakistan are presented. • Weaknesses of the renewable energy sector of Pakistan are presented. • Opportunities in the renewable energy sector of Pakistan are presented. • Threats to the renewable energy sector of Pakistan are presented. [ABSTRACT FROM AUTHOR]

Providing power to rural communities, which are far from the grid and suffer from lack of energy access in Africa, especially in Benin, in a sustainable manner requires the adoption of appropriate technology. This paper aims at analysing the techno-economic feasibility of hybrid renewable energy system (HRES) for sustainable rural electrification in Benin, using a case study of Fouay village. HOMER software is used to perform optimization, simulation and sensitivity analysis. The analysis showed that hybrid solar photovoltaics (PV)/diesel generator (DG)/battery (of 150 kW/62.5 kVA/637 kWh) is the least cost optimal system. This system ensures a reliable power supply, reduces battery requirements by 70% compared to PV/battery system and achieves 97% CO 2 emissions reduction compared to a conventional DG. Moreover, the study demonstrated that the most economical HRES depends strongly on the potential energy sources available at a location and power plant's remoteness from the beneficiary. In summary, as solar radiation is an abundant resource across the country, this hybrid PV/DG/battery system can be a suitable model to power remote areas in Benin, and we recommend it for future electrification projects in the country in place of the current widely deployed PV/battery system. • PV/DG/battery is the least costly system with a COE of $0.207/kWh. • HRES (PV/DG/battery) reduces battery storage requirements by 70%. • PV/DG/battery system has a short payback period of 3.45 years and a high IRR of 33.3%. • The robustness of the system is discussed by performing the sensitivity analysis. • Optimised HRES (PV/DG/battery) is economically more viable than grid extension. [ABSTRACT FROM AUTHOR]

About one third of people who lack electricity access worldwide reside in Africa, the most disadvantaged continent with respect to electricity access rates. Many Africans who lack electricity access are living in rural villages. Due to the low population densities of these villages, grid extension is economically unviable. Therefore, distributed generation using off-grid systems is a more favourable option for rural electrification in Africa. This study analyses the economic feasibility of small-scale wind systems for rural electrification in Africa. A spatial mapping model was used to enable the visualisation of the electrification costs of wind systems across the continent. The results of this analysis were integrated with previous work performed for photovoltaic (PV) and diesel systems. This integration produced a map indicating whether PV, diesel or wind systems are the least cost off-grid electrification option across the continent. The results show that PV and diesel systems are the most economically viable method of rural electrification in Africa, while wind systems are economically advantageous only within the horn of Africa and across few dispersed areas. This analysis can be used as a general framework for estimating the potential of off-grid wind systems using spatial mapping. Image 1 • Small-scale stand-alone wind systems were analysed for rural electrification in Africa. • Stand-alone wind systems are economically advantageous only within limited regions in Africa, particularly coastal areas. • PV and diesel systems are dominating rural electrification in Africa. • The analysis can be used as a general framework for estimating the potential of off-grid wind systems using spatial mapping. [ABSTRACT FROM AUTHOR]

Agricultural wastes are readily available in farming communities and can be utilised for off-grid electrification as an alternative to diesel generators. This work evaluates for the first time the life cycle environmental sustainability of these small-scale systems in the context of Southeast Asia. Rice and coconut residues are considered for direct combustion and gasification, and livestock manure for anaerobic digestion. Overall, anaerobic digestion is the best option for 14 out of 18 impacts estimated through life cycle assessment. The results also suggest that gasification has up to 12 times lower impacts per kWh than combustion, except for resource depletion. Combustion and gasification have 85% to two times lower impacts than diesel generators, except for eutrophication, ecotoxicity and human toxicity. Depending on the feedstock, global warming potential of anaerobic digestion ranges from being 170% lower to 41% higher than that of the diesel generator. Overall, providing power from residual biomass in small agricultural communities would reduce environmental impacts significantly while improving waste management practices. • First LCA of small-scale biomass power systems in the context of Southeast Asia. • Gasification has lower impacts than combustion of crop residues in 17 categories. • GWP of biogas from animal manure can be higher than that of diesel generator. • Power from biomass has higher eutrophication and toxicity impacts than from diesel. • Anaerobic digestion has lower impacts than biomass gasification and combustion. [ABSTRACT FROM AUTHOR]

This study quantifies the environmental and economic life cycle impacts of solar photovoltaics (PV), grid electricity and a diesel generator as power sources for pumping water in an irrigation network in Spain. It compares these energy sources in the context of on-grid or off-grid scenarios, where the PV energy is consumed solely by the irrigation pumping system (off-grid) or distributed between the pump and grid (on-grid). Overall, the results show the PV as the option with lower burdens for most environmental impact categories in both, an off- and on-grid scenario, over a 30-year lifespan. However, solar PV demonstrated a higher abiotic resource depletion burden, due to the high material demands from its manufacturing. The on-grid PV option allowed for the export of excess energy, having environmental impacts six times lower than the off-grid option. From an economic perspective, solar PV option was the cheapest energy source, despite higher initial investment. Finally, extending the grid connection to the isolated location ensures grid exports from the solar PV installation, reducing the associated impacts by between 54 and 77% for the different burden categories. Based on a 30-year lifespan, solar PV is the most economically- and environmentally-viable energy source for pumping in irrigation networks. • The environmental and economic impacts of several energy supply systems for irrigation have been analysed. • An off-grid (diesel engine) and on-grid (grid electricity) energy supply systems were compare with a PV plant. • The LCA methodology and payback period were used to determine the impacts linked to each energy supply option. • A sensitivity analysis showed the lifespan length and diesel and electricity prices influence. • The PV system presented the lowest environmental impact and life cycle cost, although it showed the highest initial investment. [ABSTRACT FROM AUTHOR]

This study performs a techno-economic analysis of concentrating solar power (CSP) technologies for Malaysia. The solar resource assessment was done by analyzing various rural and regional locations using NASA Surface Meteorology and Solar Energy database. Three different technologies, parabolic trough collector (PTC), solar power tower (SPT) and solar parabolic dish (SPD) were assessed under different economic criterions. Results based on the analysis show that PTC and SPT type plants are particularly suitable for locations at East and Peninsular Malaysia. However, considering simple payback, the net present value (NPV) and internal rate of return (IRR), it is found that PTC type CSP plant will be the most eligible for CSP plant development. Sensitivity analysis is performed to investigate the effect of the levelized cost of electricity (LCOE) on the various project discount rate. Regional renewable energy policy development and regulatory reform in feed-in-tariff (FiT), hybrid technology (PTC with biogas, solar PV and biomass) implementation, project financing under clean development mechanism (CDM) and lesson learned from international experience in local PTC equipment manufacturing are some of the crucial future policy outlooks that need to be applied for CSP technology implementation, as well as long-term sustainable renewable energy system development in the country. • Techno-economic analysis was performed for three types of CSP technologies. • Sensitivity analysis of LCOE was performed on the various project discount rate. • A policy roadmap for CSP development in Malaysia was proposed. [ABSTRACT FROM AUTHOR]

Abstract Off-grid hybrid energy systems (HESs) have become more cost-effective and reliable than single-source systems for the electrification of rural areas. This paper presents a techno-economic and environmental analysis of different hybrid systems to supply electricity to a typical Iraqi rural village. The HOMER software is utilized for the optimization of the systems using the multi-year module, which has been overlooked in the literature thus far. The analysis shows that the PV/hydro/diesel/battery HES is the most economical option with a net present cost (NPC) of $113201, in addition to having acceptable technical and environmental performance levels. Throughout the project's 20 year lifetime, PV electricity production is reduced by 9.1% while diesel electricity production, CO 2 emissions and served load are increased by 90.8%, 91.7% and 8.8%, respectively. The NPC for the multi-year module shows an increment of 22.5% in comparison with that of the single year module. Furthermore, the sensitivity analysis of some rarely reported parameters, such as water pipe losses, generator minimum load, battery roundtrip efficiency, battery setpoint state of charge, capacity shortage, PV capital cost multiplier and multi-year, demonstrated that variations in these parameters have significant effects on the system power flow and its economic analysis. Highlights • PV/hydro/diesel/battery hybrid energy systems are analyzed for different scenarios. • HOMER software is employed for the analysis using multi-year module. • Techno-economic and environmental performance of different systems are discussed. • Sensitivity analysis considering variations in several parameters is conducted. [ABSTRACT FROM AUTHOR]

Abstract Cameroon is blessed with a vast potential of renewable energy resources: solar, biomass, hydropower, wind and geothermal energies. These resources are currently poorly valorized. The country depends mainly on hydropower for its electricity supply and traditional biomass for its energy consumption. This dependency on hydropower causes acute power shortage nationwide, especially in remote communities where grid access is limited. Rural electrification is mainly conducted through costly grid extensions, small hydro and diesel plants with enormous health and environmental effects. This study assesses the feasibilities of hybrid renewable power systems for remote applications in Southern Cameroons using the climate data of Wum. HOMER was used to perform the comparative analysis. Nine hybrid systems were considered in this study based on the following components: PV module, wind turbine, micro-hydro turbine, diesel generator, battery, charge controllers, and inverters. Two energy sources and storage battery characterized each system. The PV/diesel/small hydro/battery was found to be the most viable economic system for Southern Cameroons with a 0.443$/kWh energy cost. The optimum system was proven to be very resilient to variations in streamflow, interest rate, fuel price, and PV cost. This outcome was found to be highly relevant to policy makers and investors in Cameroon. Highlights • PV/diesel/hydro/battery found to be the most viable system with a COE of 0.443$/kWh. • Outcome found to be highly relevant to policy makers and investors in Cameroon. • Hybrid off-grid renewables shows promising prospects for remote applications. • Limited studies in renewables, less state efforts to boast and revitalize the sector. [ABSTRACT FROM AUTHOR]

Abstract A methodology for optimum sizing of battery integrated biomass gasifier based distributed power generation systems is discussed. Typically, biomass gasifier systems are sized considering peak demand resulting into lower operational efficiency due to part load operation during low demand period. The proposed methodology using design space approach enables designer with multiple combinations of gasifier engine and battery systems for given load profile from which an appropriate combination may be identified considering specific objective or constraints if any. Two gasifier operational strategies are discussed and compared using cost of energy. The methodology is further extended for sizing of hybrid systems incorporating gasifier, solar PV and battery system. The proposed methodology is illustrated using a realistic load profile generated through a structured household survey of an un-electrified hamlet. For given load profile, battery integrated gasifier engine system in intermittent operation mode has the lowest cost of electricity followed by gasifier engine system alone, hybrid system and solar PV battery system. Sensitivity analysis is done to incorporate uncertainty related to variation in key input parameters. The proposed sizing methodology may be helpful in wider replication of gasification systems by providing cost effective sizing of such systems. Highlights • Methodology for optimum sizing of battery integrated biomass gasifier engine and hybrid systems. • Generation of range of feasible combinations of gasifier engine and battery system to meet given load profile. • Flexibility to select appropriate configuration based on specific objective or constraint if any. • Illustration of methodology using a realistic load profile generated through a structured household survey of an un-electrified hamlet. • Lower cost of energy with battery integrated gasifier engine system than gasifier engine system alone due to improved operational efficiency. • Sensitivity analysis for key input parameters including fuel price, transportation distance, discount rates. [ABSTRACT FROM AUTHOR]

Abstract In many regions worldwide, the electrification of rural areas is expected to be partly achieved through micro power grids. Compliance with the COP21 conference requires that such systems mainly build on renewable energy sources. To deliver a high power and quality service may be difficult to be achieved, especially when micro-grids are based on variable renewable sources. We here explore the multiscale temporal variability of the local solar resource in Africa and its implication for the development of 100% solar systems. Using high resolution satellite data of global horizontal irradiance (GHI) for a 21-year period (1995–2015), we characterize the seasonality and temporal variability of the local resource. We focus on its low percentile values which give a first guess on the size of the solar panels surface required for the micro-grid to achieve a given quality service. We assess the characteristics and especially persistence of the low resource situations, for which the local demand would not be satisfied. We finally assess how the ability of electricity consumers for some day-to-day flexibility (e.g. via the postponement of part of one day as demand to the next), would help to achieve the design level of service quality with a smaller microgrid system. Graphical abstract Image 1 Highlights • 1.1 billion people lack access to electricity in the world, 80% live in rural areas. • 100% solar microgrids (MG) are expected to provide electricity access in remote African areas. • The power service quality will depend on the seasonal and daily variability of solar radiation. • Using low percentile GHI values to design MG could help achieving a given power service quality. • Design should account for some clustering of low resource days in specific seasons or time sequences. [ABSTRACT FROM AUTHOR]

Solar home systems are recognized as a promising technology to mitigate energy poverty, promote renewable energy, and achieve Goal 7 of the United Nations Sustainable Development Goals by 2030. This study examines the determinants of solar home system adoption, with a focus on similarities and differences between households and micro-enterprises. Our original data, collected in rural off-grid villages in southern Bangladesh, reveal that households prefer relatively higher generation capacities for multiple purposes, while micro-enterprises prefer lower ones mainly for nighttime lighting. We confirm positive effects of higher economic status and negative effects of the existence of a smoker on solar home system adoption, which is similar for both households and micro-enterprises. On the other hand, households and micro-enterprises are different in two respects: (1) micro-enterprises are more likely to respond to unit prices of other alternative energy sources than households are and (2) households are more sensitive to prospects of grid expansion in the near future than micro-enterprises are. These findings imply that to progress the government’s goal of electrification for all by 2021, there are more effective ways for further promotion of solar home systems by distinguishing between the approaches to marketing for households and micro-enterprises. [ABSTRACT FROM AUTHOR]

In this paper, a novel concept of small isolated electric power generation from pumped-hydro energy storage (PHES) using wind as primary energy is proposed for rural and remote areas where the wells are available. A suitable well is utilized as the lower reservoir of the PHES system, while the upper reservoir needed for the water storage is made on the ground. In this scheme, the wind turbine, unlike other PHES schemes is not used for rotating the electric generator at all, but to rotate the hydraulic pump, which is used to suck the water from the well and to store it in the upper reservoir. The water head created in this way is utilized to run a pico-hydro turbine coupled with a generator for generating electric power. The mathematical modelling of the system has also been developed in the paper. For the validation of the model, the simulation is carried out using the actual wind speed data. The attractive features of the scheme are its low cost, simplicity, reliability and continuity in power supply at constant voltage irrespective of wind speed variations. [ABSTRACT FROM AUTHOR]

Pakistan is an agricultural country and most of its population resides in rural areas. These communities have small power demands which can easily be met through proper utilization of renewable energy technologies such as solar photovoltaic (PV). The focus of this research work is to encourage people and government to develop zero energy communities which will greatly help to achieve sustainable energy infrastructure in the country. In this paper, feasibility of a grid-connected PV power system without battery backup is conducted for the climatic conditions of a rural community located in Toba Tek Singh, Pakistan. RETScreen clean energy simulation tool is used to optimize and carry out feasibility analysis of the proposed PV system. The analysis is carried out based on project finances, fuel saving potential, energy production, capacity factor, and reduction of greenhouse gas emissions. The financial viability of the project is studied by comparing it with the grid electricity. The results indicate that the proposed PV power plant can provide energy in remote areas at relatively better rates as compared to grid electricity. Furthermore, this initiative will help to reduce the emissions of harmful greenhouse gases and to achieve a sustainable development in the country. A sensitivity analysis is also performed to demonstrate and elaborate the effects of government incentives on different decision variables. [ABSTRACT FROM AUTHOR]

Previous research has demonstrated the potential of pico-hydro turbines to provide reliable electricity in applications such as rural electrification. However, the literature has primarily focused on the development of turbine systems for design environments where spatial and flow rate constraints tend to be non-restrictive. The work detailed in this paper presents the development of a novel, compact, high efficiency turbine capable of powering a compact electrochemical cell for off-grid water disinfection. The turbine with the generator is capable of generating nearly 100 W of power with a footprint of only 8″ in length and 4″ in diameter. A basic mathematical model of a DC generator is coupled to a computational fluid dynamics (CFD) turbine model to evaluate different system configurations. Following a Taguchi Method study to computationally explore the turbine design space, experimental testing of improved turbine configurations is shown to provide electrical power output improvements of 20%. Selection of a more compatible DC generator also provides electrical power output and efficiency improvements of a factor of 2 and 2.5 respectively. [ABSTRACT FROM AUTHOR]

Wind-photovoltaic stand-alone electrification systems are a suitable option to provide electricity to isolated villages, in the right context of rural areas far from the national grid. Many initiatives promote electrification projects in rural areas spread across a territory; generally considering each village independently, implementing local microgrids. However, for the case of several neighbouring villages, a regional microgrid connecting them together may reduce costs. Determining the optimal design requires solving complex optimisation combinatorial problems to explore possible generator combinations and microgrid connections. In order to find the solution, a two-scale procedure is proposed: first, a local-scale mathematical model is developed to design a microgrid for each village; and then, a regional-scale model is proposed to design a microgrid connecting the villages together. Both models minimise the lifecycle costs and optimise supply quality, while considering the electrical requirements of end-users and solving for the location of equipment and the microgrid structure. For its validation, the two-scale procedure is considered for five small villages in La Rioja (Northern Spain); according to an Administration request to promote electrification for rural development. As a result, an optimised regional microgrid is proposed, supplying the five villages together, using medium voltage lines between them and low voltage lines internally, with generators centrally located on a windier mountain peak. [ABSTRACT FROM AUTHOR]

The aim of this paper is to model a hybrid energy system for rural India. In this analysis a hybrid renewable system consists of solar-wind-hydrokinetic-bioenergy is proposed. Overall analysis including Optimization and sensitive analysis are evaluated by HOMER software. Optimized results are evaluated considering total net present cost, cost of energy, annual electric generation, renewable fraction and CO 2 emission. The analysis is done in order to increase efficiency of the system with comparatively less cost. From this exercise it is found that, combinations of more varieties of different renewable energy system are better to fulfill futuristic demand. Futuristic demand is calculated by logistic growth model. The value of COEs ($) and total generations (kWh/yr) are 0.3563 and 133045; 0.247 and 170948; 0.242 and 179018; 0.241 and 179303 for the year (2012–2021), (2022–2031), (2032–2041) and (2042–2051) respectively. However some other combinations may produce more power, although in such cases, in order to storage excess power COE will increase. As compared to the year (2012–2021) to (2042–2051) the optimized COE of electricity is minimized, keeping Annual cost nearly constant and amount of electric generation is increased without much effect on environment. [ABSTRACT FROM AUTHOR]

Dethridge water wheel is a simple hydraulic machine originally invented for measuring volume of flow supplied to the farms. The wheel has been in widespread use for more than a century for the application of water charges in irrigated farmlands. The Dethridge water wheel resembles distinct characteristics making it a suitable device for utilising very low-head sites within irrigation canals, small streams and at the outlets of the waste water treatment plants for pico-hydropower generation. In this paper, performance characteristics of the Dethridge water wheel model is studied in different channel geometry settings. Different wheel to channel width ratios and gradual transition shapes were tested. The wheel performance improves in the channel width that is two to three times greater than the wheel width. The gradual transition shape has however insignificant impact on the performance of the wheel. [ABSTRACT FROM AUTHOR]

The application of self-sufficient off-grid electricity system using both renewable energy and storage technology can be of use in the remote isolated area. Presently, cost effective analysis dedicated for the off-grid electricity system has been conducted from the power reliability perspective. Notwithstanding the fact that reliability is comprised both of adequacy and security, the existing approaches for the analysis of power reliability are particularly associated with adequacy rather than security. The main challenge of power security in the off-grid electricity system is in ensuring the undisturbed and reliable electricity supply even after the sudden disturbances. As such, the methodology of determining the appropriate capacity size of both the renewable energy and storage technology dedicated for the off-grid electricity system taking into account the impact of sudden system failure is firstly established. Subsequently, the determination of appropriate installation from cost and power security perspective is analyzed. The developed cost-security index is explored by varying the weighting factor. Finally, the sensitivity testing is conducted to analyze the impact of uncertainties arising from the determination of weighting factor. The developed algorithm from both cost and power security perspective would hopefully help the operator to evaluate the different strategies of off-grid electricity system. [ABSTRACT FROM AUTHOR]

In developing countries, mini-grids are seen as an important option to improve electrification rates in rural areas. In order to be successful, mini-grids face issues of operation and sizing of generation capacities. Current studies on the optimal sizing of mini-grids do not include capacity expansion feedbacks regarding the operator's or investor's long-term economic performance on growth in electricity usage, e.g. gap between demand and supply impacting the operator's income. Using a System Dynamics model, this paper compares the impact from two capacity expansion strategies on rural mini-grid operator's long-term economic performance. The two capacity expansion strategies are: a strategy with minimized costs and a strategy where only diesel power is allowed. Research shows that a cost-minimized capacity expansion strategy might not be the most beneficial solution for the operator's long term financial performance. Specifically, the high investment costs prohibit the implementation of the cost-minimized expansion strategy. In addition, the diesel-only expansion strategy suffers from high operational costs, which creates long-term challenges as the share of diesel increase. Therefore, the timeline of the investments and when to implement different strategies is important, creating a benefit for a System Dynamics approach. [ABSTRACT FROM AUTHOR]