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In the context of last-mile electrification of rural communities, stand-alone solutions like Solar Home Systems are often considered an equivalent option for access to electricity as other technologies, such as minigrids and connection to the main grid. In this work, the authors question this paradigm and propose an alternative approach that takes into account the limited service, and in turn, limited development possibilities, that Solar Home Systems grant to their users. A monetary penalty is applied to this technology based on the missed services. The conceived approach is applied to a case study in the district of Cochabamba, Bolivia, thanks to the cooperation with a local NGO. Results show how the inclusion of shadow costs influences the optimal electrification strategy in terms of users connected to the main grid by up to 33%, highlighting how standard approaches tend to overlook key aspects of access to electricity linked to the possibility of development. • Different electrification strategies are not equivalent in adequacy of service. • Least-cost methods cannot effectively compare grid connection and Solar Home Systems. • We define a method to make technologies economically comparable through shadow costs. • A two-stage MILP is applied to the case study of Omereque, Bolivia. • Through this methodology more equitable electrification planning can be achieved. [ABSTRACT FROM AUTHOR]

Hybrid microgrids represent a cost-effective and viable option to ensure access to energy in rural areas located far from the main grid. Nonetheless, the sizing of rural microgrids is complicated by the lack of models capable of accounting for the evolution of the energy demand over time, which is likely to occur in such contexts as a result of the modification of users' lifestyles. To tackle this issue, the present study aims at developing a novel, long-term optimisation model formulation, capable of accounting for load evolution and performing suitable investment decisions for capacity expansion along the time horizon. Multiple scenarios of load evolution are considered to evaluate the beneficial effects of this novel approach, through the coupling of the model with a tool for stochastic load profiles generation. The results show how this implementation brings lower Net Present Cost to the project and improved correspondence between actual electricity demand and microgrid sizing. Finally, a sensitivity analysis evaluates the robustness of the approach with respect to input data variability and the Loss of Load parameter. • Evolution of the load is a key factor in microgrid sizing, usually neglected. • A microgrid sizing tool is adapted to be able to consider time evolving loads. • Trough stochastic programming the new feature is implemented in the source code. • The novel method allows consistently decreasing system costs. • First tool of its category to endogenously tackle the problem of load evolution [ABSTRACT FROM AUTHOR]

The rural electrification-based literature reports a limited knowledge of the long-term socio-economic changes that electricity access can bring in remote contexts and the consequent feedback on electricity demand. Such lack of understanding causes an inefficient allocation of economic resources for rural energy projects and inappropriate sizing processes. We model the multifaceted dimensions of the rural electricity-development nexus by formulating a system-dynamics model based on a Tanzanian case-study and using 13-years of data for calibrating it. The modelled structure provides the first quantitative step in the research committed to develop an appropriate modelling framework for deriving policy insights regarding the electricity-development nexus and the evolution of electricity demand for rural areas of developing countries. The simulation results show and highlight the dynamics behind the structural behaviour of some socio-economic system variables (e.g. income and IGAs growth), the exogenous determinants (e.g. accessibility of the rural village), and the complementary activities (e.g. micro-credit at electricity access) that allow electricity access to foster local socio-economic changes, which in turn supports the growth of electricity demand. Our findings allow increasing the understanding on the complex electricity-development nexus and providing a novel modelling framework for projecting the electricity demand for rural settings. • We employ System-dynamics to investigate the rural electricity-development nexus • We develop a simulation model for long-term projections of rural electricity demand in Tanzania • Calibration shows a mathematical good fit between data and model results • We find that the electricity-development nexus is driven by both endogenous and exogenous dynamics • A modelling framework is provided for further policy testing on the electricity-development nexus [ABSTRACT FROM AUTHOR]

The electrification-based literature reports a limited knowledge about the mechanisms of evolution of electricity demand in off-grid settings, especially in remote contexts of developing countries, due to the lack of robust and appropriate modelling frameworks. Such lack of understanding and modelling endeavour contributes to an inefficient allocation of resources for electrification projects and inappropriate off-grid sizing processes. As a first step towards the development of a more appropriate electricity demand model, we present a comparative study of two approaches for modelling different diffusion mechanisms of electricity connections: system-dynamics and agent-based models. The latter includes the modelling of social network archetypes in the simulation of diffusion processes. We model different scenarios of diffusion and we use them for evaluating the impact on the sizing process of an off-grid hydroelectric system. The results suggest that the structure of the social network can represent a crucial parameter that can impact on timing needed to complete the diffusion of electricity access – from few months to even >10 years. This affects the sizing process and the long-term sustainability of the power system, leading to variation of the hydroelectric capacity and the battery size up to around 55% and 100%, respectively. Our results indicate that the agent-based approach allows a more diversified representation of diffusion processes, but the limitations and scarcity of data can be an obstacle to their prompt application for energy application in unelectrified areas. On the contrary, system-dynamics can represent a more appropriate method since it requires less quantitative data and it provides a more structural and holistic modelling framework for conceptualising and formulating in a the determinants and complexities affecting the evolution of electricity demand in unelectrified areas. • Innovation diffusion theory is used to define local off-grid electricity access scenarios. • Agent-based modelling and system-dynamics approaches are compared. • The modelling of social interactions can impact on diffusion mechanisms. • The energy optimisation process is affected by the networks structure as diffusion processes get more complex. • System-dynamics can provide a more holistic understanding of the energy-development nexus. [ABSTRACT FROM AUTHOR]

This paper deals with an economic aspect of distributed generation systems which rural energy cooperatives may mainly support, since they can effectively coordinate the different stakeholders within an energy access initiative. Members of a rural energy cooperative would share the costs of deploying a distributed generation system, so that each of them can benefit from it. To minimise the overall investment cost, such a cooperative must consider both technical sizing and cost allocation among its members. For the latter, an important issue to take into account is the so-called willingness-to-pay. For obtaining the design of the distributed generation system we propose to use facility location covering (FALCO) models. The solution of the FALCO model provides both the structure of the distributed generation system and the investment cost to be covered by the members of the cooperative. We take advantage of the structure of the primal and dual optimal solutions of the FALCO model to endogenously determine the minimum and maximum willingness-to-pay of the cooperative members and then to apply rationing techniques to obtain the final allocation of costs to each member. Thus, our approach optimises the generator locations and minimises the total system cost, while assigning to each member at least her minimum willingness-to-pay. From our point of view, this method may help the beneficiaries to accept the investment cost allocation. Finally, a case study based on real data from a rural village in Maharashtra, where a group of farmers wanting to buy and share an energy system to pump water for irrigating their fields, is used to illustrate the working of the proposed cost allocation methodology. • Fair cost allocation methods and game theory can support distributed generation planning. • Each user minimum willingness-to-pay serves as reference for defining fair shares. • Technical and topographical conditions are critical for both system sizing and cost allocation. [ABSTRACT FROM AUTHOR]

Abstract Electric cooking (or e-cooking) based on renewable sources and highly-efficient cooking devices could represent a sustainable and reliable option to achieve the universal access to clean cooking facilities by 2030. Still, the techno-economic feasibility of e-cooking has never been evaluated through (i) a high-resolution assessment of the electric and cooking load profiles, coupled with (ii) a least-cost energy system optimisation for the related electricity supply. Hence, the present study aims at accurately investigating the techno-economic potential of a fully-renewable solar micro-grid, ensuring an integrated access to electricity and clean cooking, based on two representative case studies in Tanzania, namely: (i) a residential case study, and (ii) a community-service case study. Bottom-up stochastic load profiles are generated for the two contexts by expanding the existing LoadProGen model with a novel complementary algorithm for the computation of high-resolution cooking loads. The cost-optimised results prove the cost-competitiveness of e-cooking, especially for the community-service case, where it would require only an additional 17% capital investment due to the pre-existence of other energy-intensive activities. Moreover, the range of Levelised Cost for Cooking a Meal (LCCM) obtained for e-cooking considering the different scenarios lies within 0.16 ÷ 0.70 USD/meal, a range that is comparable with that of all other cooking options – including firewood –, and even more cost-competitive than LPG. Highlights • We propose a novel high-resolution model for electric cooking load profiles. • We couple electric cooking profiles with PV-based micro-grid optimisation. • We prove that micro-grid-based e-cooking is cost-competitive with other options. • Effect on system sizing is limited if other energy-intensive appliances are present. [ABSTRACT FROM AUTHOR]

More than half a billion people will still lack reliable and affordable electricity in 2040 and around 1.8 billion may remain reliant on traditional solid biomass for cooking. Long-term energy planning could help to achieve the energy access targets in developing countries, especially in remote rural areas. Different studies exist on long-term rural electricity and thermal energy planning, but the different foci, terminology and methodologies make it difficult to track their similarities, weaknesses and strengths. With this work, we aim at providing a critical analysis of peer-reviewed studies on long-term rural energy planning, to help researchers in the field move across the diverse know-how developed in the last decades. The work resulted in the analysis of 130 studies and categorisation of 85 of them that focus on electricity, thermal energy, and oil supply in rural areas, under a number of rules clearly defined in the first part of the paper. We classify the studies in two consecutive steps, first according to their type and afterwards according to the methodology they employ to forecast the energy demand, which is one the most critical aspects when dealing with long-term rural energy planning. The work also provides specific insights, useful to researchers interested in rural energy modelling. Few studies assume a dynamic demand over the years and most of them do not consider any evolution of the future energy load, or forecast its growth through arbitrary trends and scenarios. This however undermines the relevance of the results for the purpose of long-term planning and highlights the necessity of further developing the forecasting methodologies. We conclude that bottom-up approaches, system-dynamics and agent-based models seem appropriate approaches to forecast the evolution of the demand for energy in the long-term; we analyse their potential capability to tackle the context-specific complexities of rural areas and the nexus causalities among energy and socio-economic dynamics. [ABSTRACT FROM AUTHOR]

The causal relationships between electrification and development of poor, rural communities are complex and contextual. The existing literature focuses mainly on the impact of rural electrification and electricity use on local socio-economic development, while the reverse feedbacks of various social and economic changes on electricity demand and supply have not been fully characterized. Most electricity access impact assessments assume linear, one-way effects and linear growth in electricity demand. However, the projections rarely match the reality, creating challenges for rural utilities. From a modelling perspective, the lack of attention to dynamic complexities of the electricity-development nexus prevents the appropriate modelling of electricity demand over time and, hence, informed planning for and sizing of power plants. With the goal to improve modelling of the electricity-development nexus, we undertake a comprehensive review and extensive analysis of the peer-reviewed literature on electricity access and its impact on rural socio-economic development, and vice versa. We characterize and describe the nexus between electricity access and development through graphical causal diagrams that allow us to capture, visualise and discuss the complexity and feedback loops. Based on this, we suggest guidelines for developing appropriate models able to include and simulate such complexities. Our analysis confirms that electricity use is interconnected through complex causal relations with multiple dimensions of socio-economic development, viz. income generating activities, market production and revenues, household economy, local health and population, education, and habits and social networks. The causal diagrams can be seen as a first step of the conceptualization phase of model building, which aims at describing and understanding the structure of a system. The presence of multiple uncertain parameters and complex diffusion mechanisms that describe the complex system under analysis suggests that systems-dynamic simulations can allow modelling such complex and dynamic relations, as well as dealing with the high uncertainties at stake, especially when coupled with stochastic approaches. [ABSTRACT FROM AUTHOR]

Electricity is crucial for each country's economic and social development. More than half of the population in Sub-Saharan African (SSA) lack access to energy, which has dire consequences for the local population's living conditions, as well as affecting the local economy and increasing poverty. Renewable energy-based mini-grid (REBM) systems are the promising solution to mitigate the issue of energy access in rural areas, however, the expansion of renewable energy (RE) systems and the rate of energy access are both advancing at a slow pace. This study used PESTLE analysis (Political, Economic, Social, Technological, Legal, and Environmental) in the context of Mozambique, a SSA country, to identify the most important categories and factors to support decision-making processes by breaking down existing barriers and hurdles in the energy sector enabling them to plan and implement measures, subdivided in primary, secondary and tertiary for the development of REBM in remote settlements. Even though PESTLE analysis is rather often worldwide applied to the energy sector, its application to the Sub-Saharan context is rare, while its application to the Mozambique energy sector is absent in scientific literature. Besides, within our study, energy experts from different professional backgrounds and nationalities have been interviewed using an online questionnaire: 62 energy experts (48 Africans, and 14 Non-African) from 14 different countries assessed the categories and factors. The experts questioned identified the political category as the most crucial for policy-makers to prioritize, with the top three global weighting factors being, Clear Government policies (plan, regulation, priority, strategy) 5.79%, National financial scheme for RES investments 4.93%, and cost of investment 4.86%. The findings can support policy-makers breakdown barriers in the energy sector, planning and implementing measures for the REBM development, and contribute to achieving the SDG7 target. • Determine the categories that should be prioritized (PESTLE analysis). • Factors to promote the development of renewable energies. • Energy expert opinions for the development of mini-grids. • Propose adequate and suitable mini-grid for rural electrification. • Propose recommendation to policy-makers to mitigate renewable energy barriers. [ABSTRACT FROM AUTHOR]

In this paper, thermodynamic performances of a Waste-to-Energy power plant are evaluated by means of Exergy Life Cycle Assessment (ELCA). Environmentally Extended Input-Output Analysis is proposed as the computational structure of ELCA, allowing to account for the embodied exergy of electricity production and for the Exergy Return on (non-renewable Exergy) Investment (ExROI). Results of the analysis reveal that non-renewable resources requirement of the WtE plant is not negligible. Nonetheless, the plant is able to produce a net amount of electricity that pays back such resources requirements about a hundred times. [ABSTRACT FROM AUTHOR]

Production activities of modern economies are ultimately sustained by depletion of non-renewable fossil fuels. In the perspective of non-renewables displacement, an accurate evaluation of energy embodied in goods and services is crucial in order to select among alternative products or policies. Economic-based Input-Output models are widely used for this purpose: however, due to the increasing amount of international trades of products, definition of appropriate methods to account for the energy embodied in trades is nowadays crucial. In this paper, international trades treatment methods in Input-Output analysis are comprehensively formalized and applied to a case study based on the World Input-Output Database (WIOD). Energy embodied in final demand and in detailed products of key national energy sectors have been evaluated for the WIOD countries according to Single-Region and Multi-Regional models. It is found that an inappropriate use of international trades treatment models may produce very inaccurate estimations of numerical values of embodied energy. Three country groups has been identified, characterized by different ranges of fractions of imported/exported primary fossil fuels: Single-Region method A returns best results for countries of Group 1, with high values of fossil exports and low values of fossil imports; Multi-Regional method C is to be preferred for countries of Group 2, with high values of fossil imports and low values of fossil exports; finally, Single-Region method B returns lower deviations compared to other methods for countries of group 3, with low values of fossil imports and exports. This paper aims at supporting researchers in the field of Life Cycle Assessment in the application of Environmentally extended Input-Output analysis, finding the best trade-off between the efforts due to data collection and the accuracy of results. [ABSTRACT FROM AUTHOR]

The fixed dome digester design is the most deployed small scale biogas technology in sub-Sahara Africa (SSA). This design is deployed on mono-feedstock-wet anaerobic digestion (WAD) principle. Little or nothing has been reported in the literature on the sustainability in terms of the actual field operation and performance of this design within the SSA context. This study aims at bridging this gap and bringing additional insights to the scientific literature by investigating the sustainability of the Nepali–type fixed dome digester within the context of rural Cameroon. The investigations were evaluated in terms of operating parameters, biogas production, production rate and productivity of the digester. In addition the local investment cost of the design was analyzed. The design was operated on multiple-locally-available feedstock mixed with water at an average of 3:1 ratio resulting in a higher than design TS of 16%. The design, thus was operated towards the dry anaerobic digestion principle, highlighting insufficient mono-feedstock and water scarcity for a sustainable operation of the design within the context of rural SSA. The average biogas production was 1.2 m 3 biogas /day, giving average volumetric production rate of 0.16 m 3 biogas /m 3 digester day −1 and yields of 0.18 m 3 biogas /kg VS respectively. This low performance compared with the potential mesophilic biogas production rate of 0.27 m 3 biogas /m 3 digester day −1 could be linked to insufficient mixing of digester content and low operating temperatures. Gas storage facility (dome), skilled labour and cement made significant contributions to the investment cost of the digester. The Levelized cost of Energy from the digester was less than 1 € cents/MJ. [ABSTRACT FROM AUTHOR]

One of the most controversial topics in energy analysis consists in the internalization of the effects of human labor in the embodied energy requirements of goods and services. In this paper, the Bioeconomic Input-Output model is proposed to address such issue: it consists in a partially closed Hybrid Input-Output model in which the production of human labor is internalized within the economy as a new productive sector. The human labor sector absorbs a portion of the national final demand, while it produces working hours in order to sustain the national economic activities. The Bioeconomic model causes a reallocation of the total energy embodied in the production of goods and services due to two overlapping effects: a change in the national production technology due to the definition of the human labor sector, and a reduction in the available final demand for the consumptions of the households. The Bioeconomic and the standard Input-Output models are comparatively applied for the analysis of (1) the energy embodied in goods and services produced by the Italian economy in 2010, and (2) the primary energy requirements of alternative dishwashing solutions in Italy. Specific embodied energy in Italian products increases by less than 5% for mining and energy industries, by 5–15% for manufacturing industries and by 15–70% for tertiary sectors. On the other hand, the energy embodied in total production from each sector may be lower or greater (from −20% to +50%) with respect to results of the standard Input-Output model. Moreover, it is found that the energy embodied in dishwashing by hand and by dishwasher in Italy increases respectively by 62% and by 35% if the Bioeconomic model is adopted. Based on these results, Authors argue that human labor should methodically be included alongside the supply chain of goods and services in both embodied energy analysis and life-cycle assessment. [ABSTRACT FROM AUTHOR]

Astrocytes are crucial regulators of innate and adaptive immune responses in the injured central nervous system. Depending on timing and context, astrocyte activity may exacerbate inflammatory reactions and tissue damage, or promote immunosuppression and tissue repair. Recent literature has unveiled key factors and intracellular signaling pathways that govern astrocyte behavior during neuroinflammation. Here we have re-visited in vivo studies on astrocyte signaling in neuroinflammatory models focusing on evidences obtained from the analysis of transgenic mice where distinct genes involved in ligand binding, transcriptional regulation and cell communication have been manipulated in astrocytes. The integration of in vivo observations with in vitro data clarifies precise signaling steps, highlights the crosstalk among pathways and identifies shared effector mechanisms in neuroinflammation. [ABSTRACT FROM AUTHOR]

Access to modern energy services in developing countries (DC) is a double-faced challenge. About 1.3billion people do not have access to electricity; 2.6 billion rely on traditional use of biomass for cooking. Solutions to this energy challenge can neither be through isolated promotion of individual technologies nor fuel switching alone. A “system approach” towards a more comprehensive energy access strategy is required. Such access strategy would comprise of the supply of alternative energy carriers and planning of complete energy solutions via a more comprehensive and sustainable Rural Energy Planning (REP) i.e. Sustainable Energization (SE). Existing procedures to SE do not account for the existing energy balance and have not been demonstrated in the context of rural areas. The study aimed to propose and consolidate a more comprehensive REP procedure for SE of rural areas of DC. A seven-step procedure is proposed and its relevance and validity demonstrated through a field case study. The proposed procedure takes into account the existing energy balance and integrates energy drivers in the energy services supply network. Application of the procedure in a rural context showed a great improvement in the quantity, quality, and variety of accessible and affordable energy services for a more sustainable development of rural areas. [ABSTRACT FROM AUTHOR]

In this paper, we describe the development, implementation and application of a novel mathematical procedure devoted to formulating the daily load profiles of off-grid consumers in rural areas. The procedure aims at providing such profiles as input data for the design process of off-grid systems for rural electrification. Indeed, daily load profiles represent an essential input for off-grid systems capacity planning methods based on steady-state energy simulation and lifetime techno-economic analyses, and for the analysis of the logics to control the energy fluxes among the different system components. Nevertheless, no particular attention has been devoted so far in the scientific literature as regards specific approaches for daily load profiles estimates for rural consumers. In order to contribute to covering this gap, we developed a new mathematical procedure taking into consideration the specific features of rural areas. The procedure is based on a set of data that can be surveyed and/or assumed in rural areas, and it relies on a stochastic bottom-up approach with correlations between the different load profile parameters (i.e. load factor, coincidence factor and number of consumers) in order to build up the coincidence behavior of the electrical appliances. We have implemented the procedure in a software tool ( LoadProGen ) which can eventually support the off-grid systems design process for rural electrification. Finally, we have applied the procedure to a case study in order to clarify the proposed approach. [ABSTRACT FROM AUTHOR]

Most energy conversion systems, and especially electricity generation plants, do not operate at nominal conditions throughout their useful life: periodic, semi-periodic and stochastic changes in the availability of the resource affect solar (thermal and PV), wind, hydraulic, and geothermal plants, which in reality operate at off-design conditions for most of their life. To a smaller extent, fossil-fuelled plants may also be plagued by fuel availability problems and no longer easily predictable demand oscillation. In spite of the ever growing net connectivity, since the demand curve in even larger geographic regions displays a typical quasi-sinusoidal shape, fleet load modulation is unavoidable. Naturally, off-design operation and load cycling affect the cost of the generated kWh. This paper presents a general thermoeconomic method to evaluate the economic and environmental effects of energy system integration, taking into account life cycle concerns (supply chains) and the effect of inefficiencies due to off-design operation of the systems. The method here is applied to a realistic case study of an Italian regional utility: an analysis of the implications of the variation of the productive mix between a photovoltaic power plant (PV) and a standard commercial, non-cogenerating gas turbine plant (GT) on the final cost of the electrical kWh. The demand curve is prescribed, and the effect of different mixes is assessed, both on the monetary and on the exergy cost of the electricity. The economic cost assessment is performed by standard thermoeconomic techniques, whereas the exergy costs are evaluated using both the Extended Exergy Accounting (EEA) and the Thermo-Ecological Cost (TEC) methods. The results show that a purely monetary cash flow accounting and thermo-economics lead to contrasting results, and also that the EEA and TEC cost indicators generate different rankings among the studied alternative GT/PV mixes. [ABSTRACT FROM AUTHOR]

Despite the electrical energy scenarios are quite different between industrialized countries and emerging and developing ones, for both contexts, energy storage systems could play a key role in the next future. Specifically, in emerging and developing countries, energy storage systems may allow a cost-effective exploitation of renewable sources in order to cope with energy security for centralized energy systems, but mainly to become a building block of rural electrification by off-grid power systems. In this paper a short overview of energy storage systems within the emerging and developing countries scenarios is reported. Specifically the paper provides a description of the typical configuration for batteries within off-grid systems and an overview of the typical economic models for batteries applications and the regulatory frameworks when off-grid applications are introduced. Finally the description of an experimental project in rural area of Tanzania points out the peculiar characteristics of batteries application in off-grid applications. [ABSTRACT FROM AUTHOR]

Sphingosine 1-phosphate (S1P) is a potent bioactive sphingolipid binding to specific G protein-coupled receptors expressed in several organs. The relevance of S1P-S1P receptor axis in the pathophysiology of immune and nervous systems has encouraged the development of S1P receptor modulators for the treatment of neurological, autoimmune and/or inflammatory disorders. Currently, four S1P receptor modulators are approved drugs for multiple sclerosis (MS), an inflammatory disorder of the central nervous system. As main pharmacologic effect, these treatments induce lymphopenia due to the loss of responsiveness to S1P gradients guiding lymphocyte egress from lymphoid organs into the bloodstream. Recent data point to immunological effects of the S1P modulators beyond the inhibition of lymphocyte trafficking. Further, these drugs may cross the blood-brain barrier and directly target CNS resident cells expressing S1P receptors. Here we review the role of S1P signalling in neuroimmunology at the light of the evidences generated from the study of the mechanism of action of S1P receptor modulators in MS and integrate this information with findings derived from neuroinflammatory animal models and in vitro observations. These insights can direct the application of therapeutic approaches targeting S1P receptors in other disease areas. [ABSTRACT FROM AUTHOR]

Highlights: [•] The model proposed aims at minimizing local impact of energy systems. [•] The model is meant to minimize the impact starting from system thermodynamics. [•] The formulation combines exergy analysis and quantitative risk analysis. [•] The approach of the model is dual to Thermoeconomics. [ABSTRACT FROM AUTHOR]

In light of a national policy aiming at satisfying a growing demand for electricity, while achieving a greater diversification of power generation technologies and full electrification by 2050, this research models and contrasts alternative electrification pathways for Tanzania in the time frame 2015–2040. The study relies on an improved model grounded on the OSeMOSYS framework. GIS data are used both to determine the electricity demand projections and to inform the decision about the optimal production technologies made by OSeMOSYS with a least-cost criterion. Findings indicate that the stated policy goals (New Policy scenario) are within reach, but they also imply an increase in installed capacity from less than 2 GW to at least 13.8 GW, corresponding to an investment of 25.3 billion USD, which is significantly above historical spending in the power sector. Also, only an additional environmental policy (450TZ scenario) would ensure that the carbon intensity of the power sector lowers from a current 440 gCO 2 /kWh to around 100 gCO 2 /kWh in 2040, with the additional benefit of a lower average cost of providing electricity (compared to the New Policy scenario). An Energy For All scenario where universal access is achieved two decades earlier (in 2030) is also feasible but implies more difficulties in lowering carbon intensity or the cost of providing electricity. Results for universal access are the object of a separate in-depth discussion and a sensitivity analysis looks at the effect of key assumption (e.g., on demand projections and discount rate) on the main results. • Alternative electrification pathways to 2040 for Tanzania are modelled via OSeMOSYS. • GIS data inform electricity demand projections and least-cost production choices. • Satisfying demand implies investing in the power sector way above historical levels. • A dedicated policy is necessary to decrease carbon intensity of the power sector. • Achieving universal access earlier challenges environmental and economic gains. [ABSTRACT FROM AUTHOR]

Abstract To support the ongoing transition towards smart and decarbonised energy systems, energy models need to expand their scope and predictive capabilities. To this end, this study proposes a multi-layer modelling methodology that soft-links (i) a stochastic bottom-up load curves estimation model, (ii) a technology-rich energy system optimisation model (Calliope) and (iii) a Multi-Regional Input-Output model (Exiobase v.3), and applies it to investigate the economic and environmental consequences entailed by a massive replacement of traditional gas-fired kitchens with induction kitchens within the Italian residential sector. Two scenarios are considered for the analysis: (i) business as usual (BAU, 2015 energy system configuration), and (ii) national energy strategy (SEN, configuration prospected in 2030). The results show how the intervention produces positive net effects on the primary energy balance of the energy sector only when sustained by adequate shares of renewables, as in the SEN (−1.5 TWh∙y−1); otherwise, increased operation of fossil-fuel plants offsets gas savings (BAU, +2 TWh∙y−1). Nonetheless, feedbacks on other productive sectors entail additional energy consumption and emissions, thus counterpoising positive effects obtained within the energy sector even in the SEN scenario. Still, higher renewables penetration reduces overall additional emissions from 2.07 Mton∙y−1 for BAU to 0.88 Mton∙y−1 for the SEN. Highlights • A multi-layer methodology to link energy models and input-output models is proposed. • Italian electricity demand due to massive electrification of cooking devices is assessed. • Change in the Italian power production mix is assessed based on Calliope energy model. • The related economic/environmental implications are assessed with the Exiobase model. [ABSTRACT FROM AUTHOR]

Improved Cooking Stoves (ICSs) represent the most commonly promoted solution to alleviate the burden associated with the use of traditional biomass in a short-term perspective. However, criticism is raising about the methodologies used for assessing their performance, with a particular focus on laboratory-based testing protocols. One of the key weaknesses of current protocols consists in the inaccurate and biased approach adopted for reporting and statistically analysing test results, which can lead to misleading conclusions about the actual improvements ensured by ICSs. This study proposes a robust procedure to deal with the statistical analysis of small sample sizes, and subsequently verify it through its application to an experimental comparison – based on the Water Boiling Test – between three models of stove. The results show that the current practice based on 3 or 5 replicates often produces biases in the analyses, as at least 13 replicates might be needed to achieve reliable results. Moreover, the study shows how the t-test is in most cases improperly applied, while the proposed procedure allows to deal both with normally and of non-normally distributed data sets in a robust way. In one case, the apparent improvement of an ICS model as compared to the three-stone fire, is refuted by the application of our procedure. [ABSTRACT FROM AUTHOR]

Faults and malfunctions occurring in engineering systems may cause additional resources consumptions and economic expenditures, thus their detection and isolation is of great practical significance. The procedure to discover faults is known as diagnosis , and it can be based on different techniques, depending on the purpose of the analysis: to predict the failure time of the component, or to quantify the inefficiencies of the system due to the anomaly. Among the existing approaches adopted to diagnose the energy systems, Thermoeconomic diagnosis provides useful information to detect the anomalies and to quantify its negative impacts. However, this method does not allow to identify possible strategies useful to reduce the inefficiencies caused by anomalies, which could be a crucial need for the system operator. To face this issue, this article proposes a method to perform Thermoeconomic diagnosis of energy systems that enables the analyst to understand the interdependencies between the components, and decomposing the main indicator resulting from Thermoeconomic diagnosis, known as malfunction. The method provides useful information for the system operators to define practical strategies to reduce the negative effects of malfunctions. This approach is also formalized and applied to the CGAM benchmark to highlight the practical achievements of this approach with numerical values. It is found that the proposed approach provides useful insight about the effects of malfunctions, and it may be helpful for system operators to reduce the negative impacts of the anomaly by pinpointing the component with higher contribution in total inefficiency of the system. In this specific case, proper intervention on the pinpointed component mitigated the total inefficiency of the system by almost 40%, and recovered the reference efficiency of the system. [ABSTRACT FROM AUTHOR]

Understanding the energy metabolism of national economies is nowadays crucial for policymakers in order to define effective policies and to properly set energy efficiency targets. Energy accountings based on the traditional Production-based accounting method (PBA) allows to understand how primary energy is directly extracted, traded, transformed and used within each economy. On the other hand, Consumption-based accounting method (CBA) allows to understand the ultimate economic purposes of such energy flows. The information provided by the joint application of these approaches may provide useful and complementary insight on the national energy metabolism, allowing to identify hotspots for potential interventions from both the supply and demand side. This paper reviews PBA and CBA energy accounting methods, presenting a possible way for the joint use of their results, consistently represented by means of one unique Sankey diagram. This will be useful to have a comprehensive insight on the energy metabolism of national economies, supporting analysts and policymakers in the identification of energy efficiency hotspots. The method is applied to South Africa and to the neighbor country of Botswana, based on data provided by IEA energy statistics and the EORA26 Multi-Regional Input-Output model, taking into account non-renewable fossil energy (raw coal, crude oil and natural gas) and considering the reference year 2013. Results suggest that the joint use of PBA and CBA methods may provide useful information on the hidden energy links among national economies, helping analysts and policymakers in defining alternative energy efficiency policies. For this reason, the Authors argue that results of CBA should be provided alongside energy statistics based on the traditional PBA approach. [ABSTRACT FROM AUTHOR]

Laboratory protocols based on water heating procedures represent the most widespread tool for the evaluation of Improved Cooking Stoves (ICSs) thermal performance. Nevertheless, the performance of the cooking system can vary substantially when the boundary conditions – ambient conditions, burn sequence – differ from those experienced in a specific lab. Consequently, we developed and experimentally validated a Cooking Stoves Thermal Performance Simulator (Cook-STePS), based on a 1-D heat and mass transfer model and implemented in an Excel ® and VBA environment, in order to provide additional information about how the performance of a cooking system would change, in selected conditions, as compared to the baseline laboratory performance. The study shows how the tool can be effectively applied to a generic cooking system through a two-steps procedure, based on (i) a preliminary set of experimental tests in controlled conditions and (ii) the simulation of performance in the desired conditions. [ABSTRACT FROM AUTHOR]

In the last decades, thermoeconomic analysis emerged as a combination of exergy analysis and cost accounting principles, widely used for multiple purposes: to account for the exergy and economic costs of energy systems products, to derive the structures of such costs for the design optimization purpose, and to perform system diagnosis quantifying the source and the impact of malfunctions and dysfunctions within the analyzed process. Traditionally, thermoeconomic analysis is referred to as Exergy Cost Analysis or Exergoeconomic Cost Analysis. The former is based on the so-called Exergy Cost Theory, focused on the evaluation of exergy cost of the system products, while the latter is focused on the evaluation of monetary cost following the same theory. Currently, many practical approaches are available in the literature for the application of thermoeconomic analysis and Exergy Cost Theory to energy conversion systems, while a comprehensive classification, benchmarking and comparison of such approaches is missing. This paper aims to fill this gap through the following activities: first of all, a brief but comprehensive literature review related to the theoretical developments and applications of thermoeconomic analysis method is performed. Secondly and for the purpose of benchmarking, the main practical approaches identified for the application of Exergy Cost Theory are presented and formalized, including the fundamental aspects related to the definition of auxiliary relations and the reallocation of the exergy cost of the residues. Finally, the identified approaches are comparatively applied to the standard CGAM problem, and the advantages and drawbacks of each approach are discussed. It is found that the definition of the functional diagram and the numerical solution of the system through input-output analysis seem to be more straightforward with respect to the other approaches, leading also to the formalization of an unambiguous method to reallocate the exergy cost of the residual flows. [ABSTRACT FROM AUTHOR]

Exergy Life Cycle Assessment (ELCA) is proposed by literature to account for the exergy embodied in products of energy systems. In order to make results of ELCA comparable, supply chains that support the life cycle of the system should be analyzed through a unified model: this is one of the main concerns related to Life Cycle Assessment and Industrial Ecology disciplines. In this paper, Hybrid Input-Output analysis is proposed as the computational structure of ELCA: according to this method, national supply chains are modeled through the Monetary Input Output Tables (MIOTs) of national economies, a constantly updated and freely available data source. Then, the adopted national MIOT is expanded to include the detailed model of the considered energy system, hence defining a Hybrid Input-Output model. The (non-renewable) exergy embodied in electricity production and the Exergy Return on Investment (ExROI) are defined as the appropriate performance indicators based on ELCA. The introduced model is here adopted for the analysis of a Waste-to-Energy (WtE) power plant currently operating in the Italian context. It is found that the primary non-renewable exergy embodied in electricity produced by the analyzed WtE is non-negligible for both the construction (127.1 toe) and the operation phases (11.6 toe/y). Nonetheless, the plant is able to produce a net amount of electricity that pays back such primary non-renewable resources requirements about a hundred times. Finally, the joint application of Exergy Analysis and ELCA lead to improve the overall thermodynamic performances of the WtE system, increasing its exergy efficiency by 1%, and reducing the non-renewable exergy embodied in electricity production by 7938 toe. [ABSTRACT FROM AUTHOR]

Off-grid renewable systems can play a pivotal role in the process of rural electrification, thus promoting local development. Moreover, scientific literature is increasingly addressing this issue through the concept of sustainability and appropriate technologies. With regards to this topic, we present a sizing methodology which better relates the results and the sizing process itself to the local context. Specifically, we address the research area of sizing methodologies for off-grid PV systems. Typically, the Loss of Load Probability (LLP) is a key parameter in these methodologies, but is difficult to set as regards the specific context. The proposed methodology employs the concept of Levelized Cost of Supplied and Lost Energy, it is based on the estimate of an economic Value of Lost Load, and eventually, the LLP results to be an output of the process. Therefore, the methodology uses only data characterizing the local situation and results better fit with population conditions. We also propose a simple approach to compute the Value of Lost Load and we apply the methodology for a rural area of Uganda. The results show that the methodology identifies a reliable system which supplies electricity with a fair cost while minimizing the energy bill of the consumers. [ABSTRACT FROM AUTHOR]

Russia's invasion of Ukraine fuelled an energy crisis, which considerably impacted Europe given its heavy reliance on Russian natural gas imports. This study uses an ensemble of four global integrated assessment models, which are further soft-linked to two sectoral models, and explores the synergies and trade-offs among three approaches to living without Russian gas in Europe: (a) replacing with other gas imports, (b) boosting domestic energy production, and (c) reducing demand and accelerating energy efficiency. We find that substituting Russian gas from other trade partners would miss an opportunity to accelerate decarbonisation in end-use sectors while risking further fossil-fuel lock-ins, despite featuring the lowest gas price spikes and potentially reducing heating costs for end-users in the near term. Boosting domestic, primarily renewable, energy production on the other hand would instead require considerable investments, potentially burdening consumers. Energy demand reductions, however, could offer considerable space for further emissions cuts at the lowest power-sector investment costs; nonetheless, an energy efficiency-driven strategy would also risk relocation of energy-intensive industries, an aspect of increasing relevance to EU policymakers. • Three 'corner' strategies to replacing Russian natural gas in the EU are explored. • EU climate targets can still be reached in all three strategies, but costs increase. • Promoting energy efficiency or domestic renewables can boost end-use decarbonisation. • An 'energy efficiency first' response may save millions € in annual electricity costs. • Southern Europe is the most vulnerable to high electricity prices across strategies. [ABSTRACT FROM AUTHOR]

Energy access projects in remote off-grid areas would benefit from the adoption of a multi-energy system perspective, addressing all energy needs – not only lighting and power appliances, but also water-heating and cooking – by means of a mix of energy vectors. However, multi-energy analyses in remote areas are hindered by a lack of models allowing for the generation of multi-energy load profiles based on interview-based information characterised by high uncertainty. This study proposes a novel open-source bottom-up stochastic model specifically conceived for the generation of multi-energy loads for systems located in remote areas. The model is tested and validated against data obtained from a real system, showing a very good approximation of measured profiles, with percentage errors consistently below 2% for all the selected indicators, and an improved accuracy compared to existing approaches. In particular, some innovative features – such as the possibility to define and modulate throughout the day appliances' duty cycles – seem to be determinant in marking a difference with previous approaches. This might arguably be even more beneficial for case studies characterised by a larger penetration of appliances that are subject to complex and unpredictable duty cycle behaviour. • A model for generating load profiles for systems located in remote areas is designed. • The model is stochastic, open-source and conceived for multi-energy analyses. • Innovative features allow to model also complex and variable duty-cycles. • Validation against measured profiles proves consistent model accuracy. • Open-source nature allows customisability and context adaptability. [ABSTRACT FROM AUTHOR]

Abstract The production of Liquefied Natural Gas (LNG) from natural gas reservoirs with high content of acidic compounds is expected to be a strategic and crucial issue for the development of the natural gas market in future decades. Therefore, the identification of alternative suitable processes for the synergistic natural gas purification and LNG production, when the amount of CO 2 in the raw gas feed is high, and their comparative thermodynamic assessment, is necessary to foster a cleaner and efficient production of LNG. In this paper, the energy intensity of the classical chemical absorption units using aqueous solutions of Methyldiethanolamine (MDEA) and the novel Dual Pressure Low-Temperature Distillation process (DPD) operating in different national contexts is assessed by means of the Net Equivalent Methane analysis and the Energy Life Cycle Assessment. These methods return respectively the equivalent methane and the embodied non-renewable energy invoked by the two alternative processes in one operating year. In general, the primary energy required by the construction phases of both the systems results negligible compared to the operation phase, and most of the latter is due to the consumption of energy utilities, which is strongly dependent by the considered national context. According to the results obtained by means of both the methodologies, the DPD process is generally less energy intensive compared to MDEA: the DPD process results to be an efficient and promising technique to perform the synergistic natural gas purification and LNG production. Highlights • Exploitation of acidic natural gas reserves and LNG production will play key role in future decades. • Two alternative processes for acid natural gas purification and LNG production are introduced. • Net Equivalent Methane method and Energy LCA of the processes are comparatively applied. • Both the methods confirm that Dual Pressure Low-Temperature Distillation has the lowest energy intensity. [ABSTRACT FROM AUTHOR]

Abstract Rural electricity plans are usually designed by relying on top-down rough and aggregated estimations of the electricity demand, which may fail to capture the real dynamics of local contexts. This study aims at soft-linking a bottom-up approach for short- and long-term forecasts of load profiles with an energy optimisation model in a more comprehensive rural energy planning procedure. The procedure is applied to a small Indian community, and it is based on three blocks: (i) a bottom-up model to project households' electrical appliances, which adopts socio-economic indicators to make long-term projections; (ii) a stochastic load profile generator, which employs correlations and users' habits for assessing the coincidence and load factors; (ii) an energy optimisation model based on OSeMOSYS to find the economic optimum. The simulations show that demand models based on socio-economic indicators lead to more structured and less arbitrary scenarios. The soft-link with the energy optimisation model confirms that when accounting for short- and long-term variabilities of electricity demand together, the optimal capacities and costs can vary up to 144% and 50% respectively. Integrating optimisation tools to bottom-up models based on socio-economic indicators for forecasting electricity demand is therefore pivotal to set more reliable investments plans in rural electrification. Graphical abstract Image 1 Highlights • A bottom-up model for local electricity demand in rural India is revised. • A stochastic model accounts for short-term uncertainty. • Using socio-economic indicators leads to less arbitrary demand scenarios. • A soft-link with a long-term rural energy optimisation model is developed. • The optimal planning is very sensitive to short- and long-term demand variations. [ABSTRACT FROM AUTHOR]

Abstract In this article, the economic and environmental implications due to the projected evolution of the power sector in Egypt until 2040 are assessed and discussed. The Reference Energy System (RES) of the Egyptian power sector has been defined and implemented in the Open Source Energy Modelling System (OSeMOSYS), based on two different energy scenarios. To increase the accuracy of the analysis, the discount rate on capital investments for the energy technologies has been imposed as a time dependent exogenous variable. Moreover, the robustness of the obtained results has been tested through a sensitivity analysis on the main exogenous parameters. It is found that Combined Cycles, Wind, and Photovoltaic rooftop systems are compatible technologies to be included in the future Egypt's power generation mix. In particular, based on the abundant Egypt's renewables resources endowments, wind power technology comes first in achieving the proposed target on renewables penetration in the country's generation mix, and it might be a feasible alternative to replace a part of the natural gas share. Moreover, the significant impact of discount rate on capitals on the final results is highlighted: low values of discount rate would skew generation mix to include higher investment cost technologies and vice versa. Highlights • Implications of future energy scenarios in Egypt have analyzed based on OSeMOSYS. • Sensitivity analysis has performed on relevant techno-economic scenario parameters. • Combined cycles, wind and PV are key technologies in future Egypt's power mix. • Efficiency of combined cycles is relevant in reducing power cost and emissions. • Wind technology may replace a part of natural gas share in the electricity mix. [ABSTRACT FROM AUTHOR]

Alternative fuel policies need accurate and transparent methods to find the embedded carbon intensity of individual refinery products. This study investigates different ways of allocating greenhouse gases emissions deriving from refining and upstream crude oil supply. Allocation methods based on mass, energy content, economic value and, innovatively, added-value, are compared with the marginal refining emissions calculated by CONCAWE’s linear-programming model to the average EU refinery, which has been adopted as reference in EU legislation. Beside the most important transportation fuels (gasoline, diesel, kerosene/jet fuel and heavy fuel oil), the analysis extends to petroleum coke and refinery hydrogen. Moreover, novel criteria, based on the implications due to hydrogen usage by each fuel pathway, have been introduced to test the consistency of the analyzed approaches. It is found that only two economic-based allocation methods are consistent with the introduced criteria. These two methods also give negative refinery emissions for heavy products, which is coherent with the marginal emissions calculated through the CONCAWE refinery model. The recommended allocation methods are transparent and use only publicly available statistical data, so they may be useful not only for future EU legislation, but also in jurisdictions where a representative refinery model is not available. [ABSTRACT FROM AUTHOR]

Around 2.7 billion people rely on biomass fuelled inefficient devices for cooking and heating. Improved Cooking Stoves are promoted as a means to mitigate the economic, environmental and social implications of this practice. However, their diffusion is hindered by a number of factors, including in particular the lack of agreement on performance evaluation methodologies. Laboratory protocols are designed to give useful indications to cookstoves developers, in order to improve their performance under controlled conditions, while field protocols provide the assessment of real performance of a cookstove in a given context. However, due to high time and finance requirements of the latter, lab results are often used also for stoves selection, also because of a general misunderstanding regarding their correct utilisation. In this work, we provide a review of all lab protocols officially published to date, comparing conceptual and technical aspects. We find that no protocol takes into account all the relevant factors at once. As a result, lab tests carry little information about real field performance, and can be misleading regarding stoves optimisation. Therefore, the analysis reveals the need to define better standards, regarding: (i) repeatability, metrics and statistical analysis of results; (ii) burn sequences calibrated from time to time according to the specific user. [ABSTRACT FROM AUTHOR]

Due to the rapid increase of the World’s primary energy demand of the last decades, low-temperature processes for the purification of natural gas streams with high carbon dioxide content has gained interest, since they allow to make profitable exploitation of low-quality gas reserves. Low temperature purification processes allow the direct production of a methane stream at high purity and at low-temperature, suitable conditions for the direct synergistic integration with natural gas cryogenic liquefaction processes, while CO 2 is obtained in liquid phase and under pressure. In this way, it can be pumped for transportation, avoiding significant compression costs as for classical CO 2 capture units (where carbon dioxide is discharged in gas phase and at atmospheric pressure), and further uses such as Enhanced Oil Recovery (EOR) or underground storage. In this paper, the three most common natural gas low-temperature purification techniques have been modelled and their performances have been evaluated through energy and exergy analyses. Specifically, the dual pressure low-temperature distillation process, the anti-sublimation process and a hybrid configuration have been considered. It is found that the dual pressure low-temperature distillation scheme reach the highest thermodynamic performances, resulting in the best values of exergy efficiency and equivalent methane requirements with respect to the other configurations. This is mainly due to the distributed temperature profile along a distillation column, resulting in a less irreversible heat exchanging process. [ABSTRACT FROM AUTHOR]

Access to electric power supply has always had a significant role in promoting improvements in all the society sectors, nevertheless nowadays 1.3 billion of people still do not have electricity access. Moreover, most of them live in rural areas of developing countries which are often isolated, scattered populated and characterized by poor infrastructure and services. In this situation, the growing consideration towards the target of universal access to energy has emphasized the role of rural electrification, and off-grid small-scale generation represents one of the most appropriate options. As a consequence, the scientific literature has devoted attention to this topic with a large number of papers. In this frame, the present analysis focuses on off-grid systems for rural electrification and provides a general framework to this topic and an analytical review of the literature. The work is based on the review of more than 350 papers mainly published from 2000 to 2014 within selected journals, and it is organized in two sections. In the first one we describe the role of small-scale generation systems throughout the process of electrification, the main features of rural areas and their typical energy uses, and we propose a new comprehensive taxonomy for off-grid systems for rural electrification. In the second one we develop an extensive review of the selected literature according to the proposed classification and to five main research areas: Technology: layout and components; Models and methods for simulation and sizing; Techno-economic feasibility analyses and sustainability analyses; Case studies analyses; Policy analyses. The work results in a comprehensive review which organizes and capitalizes the main fundamentals of the addressed topic and provides elements to get acquainted with the literature. [ABSTRACT FROM AUTHOR]

This paper proposes an exergy-based well-to-wheels analysis to compare different passenger vehicles, based on three key indicators: petroleum energy use, CO 2 emissions, and economic cost. A set of fuel pathways, including petroleum-based fuels, compressed natural gas, biofuels, and electricity are considered in five representative national energy mixes, namely Brazil, China, France, Italy, and the United States of America. Results show no fundamental difference in the fossil fuel pathways among the five scenarios considered. Compressed natural gas vehicles and electric vehicles can completely displace oil consumption in the personal transportation sector. Compressed natural gas vehicles also reduce CO 2 emissions by over 20% compared to gasoline vehicles. Emissions from electric vehicles greatly vary depending on the electricity mix. In low-carbon electricity mixes electric vehicles reach almost-zero CO 2 emissions, while the use of biofuels leads to the lowest CO 2 emissions in carbon-intensive electricity generation mixes, where vehicles running on E85 could reduce CO 2 emission by over 50% compared to gasoline vehicles. Hybrid electric vehicles show the lowest overall economic cost, due to improved efficiency and low cost of petroleum-based fuels. Vehicles running on electricity are characterized by significantly higher capital cost and lower operating costs. Thus, different electricity generation costs impact minimally the overall cost. These results can be used to inform decision-makers regarding the multi-dimensional impact of passenger vehicles, including environmental impact, economic cost, and depletion of primary energy resources, with particular focus on petroleum. [ABSTRACT FROM AUTHOR]

In this work, the primary resources assessment of four different soil erosion remediation technologies, Geo-nets , Bio-mats , Geo-cells and Deep Rooting Plants (DRP), is performed applying the approach of the Exergy Life Cycle Assessment (ELCA). The ELCA provides a comprehensive framework to assess the primary resources requirements of products by means of the conversion of primary flows of energy and raw materials absorbed by a production process into exergy. The soil erosion technologies described in the work are analysed according to two complementary indicators: the annual average soil loss and the life cycle primary exergy requirements. The primary exergy requirement of the different applications is measured by means of three ELCA indicators: the Cumulative Exergy Demand (CExD), the Thermo-Ecological Cost (TEC) and the Cumulative Exergy Extraction from Natural Environment (CEENE). The specific context of the application is a highway slope of the size of 1 hectare situated along the A1 highway, near the town of Fabro (TR), in Italy. The results indicate that DRPs are the most suitable solutions. However, TEC, CExD and CEENE indexes of these technologies suggest the existence of hidden impacts related to land use. The same result characterises also Bio-mats, the technology with the highest contribution of renewable material along the life cycle phases. In conclusion, this work shows that the use of exergy based impact indexes for the environmental impact assessment supplies a wider framework and deeper insights of the environmental performance of production processes and products. [ABSTRACT FROM AUTHOR]

Achieving sustainable energy development in a region requires rational use of energy resources and technologies, and the development of appropriate policies. Three concerns are therefore required to achieve these issues: (i) to acquire a picture of the local current energy situation, (ii) to measure the state of development and the progress towards a sustainable energy system, and (iii) to have energy decision- and policy-makers fully aware of the implications on sustainable development of selected policies. It is in this perspective and in the frame of activities on sustainable energy for all and access to energy in developing countries carried out by the UNESCO Chair in Energy for Sustainable Development, that we developed this review. The objective of this paper is to depict the current energy situation of Africa by using the most up to date data, describing it as far as the concept of sustainable development is concerned, and to see if and how energy policies promoted by local players fit with this asset. We assess the energy situation of Africa by combining (i) data, mainly by the International Energy Agency, about national energy balances for primary and electric energy, the Energy Development Index and energy resources, with (ii) a more comprehensive analysis of the African energy system, accomplished by the Energy Indicators for Sustainable Development. An overview of the energy-related policies and action plans developed by different local players in the African continent is also carried out with the goal of providing remarks by coupling such plans with the above mentioned energy analysis. [ABSTRACT FROM AUTHOR]