Search

Off-grid systems, and mini-grids in particular, are expected to play a significant role in improving electricity access to one billion people until 2040. One of the major challenges for mini-grids is associated with their high costs, low financial viability and local development impact. Productive use of electricity can be an important driver of local development and impacts the total load in a mini-grid. By using a mixture of high-resolution (minutes) measurements and long-term data (years) on electricity expenditures and purchased electricity from a mini-grid in the Tanzanian highlands, we analyse the technical and economic impact from household and productive use of electricity, respectively. The high-resolution data is analysed using performance indicators and the long-term data using regression tools. We find that a mixture of household use and productive use of electricity provides both technical and economic benefits for the operator. In addition, we find that while productive use customers only represent 25% of the customers, they generate 44% of the operator's income. Furthermore, productive use of electricity customers are also likely responsible for the peak demand in the mini-grid, which occurs during day time. Lastly, we find empirical evidence suggesting that expenditures and demand are unit elastic, which has implications on economic policies for supporting rural electrification.

One option to improve electricity access to the one billion people currently lacking electricity access is autonomous mini-grids. Most of the unelectrified communities are located in rural areas far from the current grids. Rural area communities are characterized by geographical remoteness, dispersed consumers, low consumption, and limited ability to pay. The low consumption and limited ability to pay can affect the revenue of the mini-grid operator and owner, often leading to low cost-effectiveness of the mini-grid. However, as shown in the current work, correctly combining the number of household and productive users in a mini-grid can increase revenue by 40 % compared to only households if an equal tariff is considered for both customer groups.

This paper presents a case study of a minigrid powered by a small hydro plant in the southern highlands of Tanzania. The approach was chosen to provide in-depth understanding on benefits and challenges facing a rural minigrid. The case focuses on productive use; i.e. electricity as a direct input to the production of goods or provision of services. The study applies an interdisciplinary approach consisting of a mix of qualitative and quantitative methods, which included stakeholder and user interviews and measurements of output power and water flow. The analysis shows that certain entrepreneurial activities emerged as an outcome of electricity access thru the minigrid; barber shops, welding machines, mobile phone charging, salons, photo copy, and lighting business centres. Major challenges are related to the initial set up of the mini-hydro power plant, i.e. to only service the hospital, as the idea and need for building a minigrid developed much later. A tentative conclusion is that subsidized electricity will not promote rural businesses unless other criteria are met. Moreover, the minigrid faced a number of technical problems partly because of lack of adequate technical resources such as technicians and spare parts but also from the poor-planning and non-saving culture. The study concludes that the minigrid has led to productive uses that are found elsewhere in grid-connected rural communities. The finite supply of energy however means that there are restrictions using electricity for certain productive use – there is a load shedding schedule in place for some of the power intensive machines - due to overload caused by the load and large number of connections. Finally, there is apparent room for improvement not the least regarding the tariffs, which do not reflect market price and hence may affect the sustainability of the system.

Biogas is a locally accessible and renewable energy source that can be generated from organic feedstocks under anaerobic conditions. This paper aims to assess the future biogas potential in India from varied sources (crops residues, animal manure, municipal solid wastes, municipal and industrial wastewater). The study uses a bottom-up, resource focused approach for the assessment of biogas potential. The paper assess agriculture and animal residues as well as generation, collection and availability of municipal and industrial waste for biogas production. The results show considerable potential of biogas in the next two decades due to rising waste generation and deployment of infrastructure for improving waste collection efficiency. The analysis estimates that the biogas potential ranges from 310 to 655 billion m3/year in the year 2040 depending upon availability of different resources. The estimated biogas potential in the year 2040 is around 36% of India's current (2015) total primary energy supply in the high availability scenario. Finally, the paper offers policy recommendations aimed at realizing the biogas potential.

Mini-grids are considered important in order to improve access to electricity in developing countries. Their technical and organizational independence from the large national grids and their interactions with local social, economic, and environmental factors suggests that system dynamics is a useful method of analysis. However, the successful implementation of mini-grids in rural electrification has partly been prevented due to complexity issues, making problem formulation difficult. Most problem-solving methods, such as system dynamics, require well-defined problems. Previous work on the problem formulation process in system dynamics is limited. This work presents a conceptual framework for tackling complexity and uncertainties in rural electrification. The conceptual framework is general and draws on research in conceptual modelling and system dynamics. The focus is on the learning that can be achieved from a system description and how it can be used to tackle complexity by reducing uncertainties and improving knowledge.

Energy transitions at the household level are important because there are so many households, and motives and barriers to these transitions processes are not well understood. The objective of this paper is to investigate explanatory variables of household energy transitions. We select papers investigating explanatory variables underpinning household energy transitions in three domains: adoption of solar photovoltaics (PV) in households, adoption/transition to sustainable residential heating systems (RHS) and adoption/transition to alternative fuel vehicles (AFVs). In all three domains the chosen literature employ a wide variety of quantitative analyses such as discrete choice models ranging from multinomial logit models and principal component analysis to qualitative assessment of the answers through inductive analysis. The explanatory variables are categorized in six superordinate explanatory variable categories of economic factors, environmental factors, personal preferences and values, social factors, household characteristics and market and policy factors. In total we identify 31 explanatory variables which have been investigated in the 38 articles chosen, falling under the six categories. Investment cost is an important explanatory variable for all three domains, but a policy variable such as government subsidy could mitigate the former explanatory variable. We propose a conceptual framework as an initial step towards understanding the interactions and impacts of the explanatory variables with each other.

Long-term energy demand forecasting is crucial for any country, in particular for developing countries with rapid developments of energy needs. This study focuses on Ethiopia, a country with a highly increasing energy demand resulting mainly from the currently low share of electricity access, rapid development of industrial parks, extensive expansion of the railway network, extensive irrigation schemes for agriculture, new cement and sugar factories, housing projects, power export plan to neighboring countries, etc. These all are on top of the 2.7% average population growth. In this study, the Long-range Energy Alternatives Planning System (LEAP) is used to explore different possible futures and also to forecast the long-term energy requirements in Ethiopia. The planning period is 33 years from 2018 to 2050. The study employs six different scenarios to unfold the future evolution. The developed scenarios are Business-As-Usual (BAU), Growth in Electrification and Urbanization (E&U), High Economic Growth (HEG) and three policy-driven, Improved Energy Efficiency (IEE-1, IEE-2 and IEE-3) scenarios. The pathways represented by these scenarios can show the maximum expected rise in demand under different drivers and the best-case energy saving opportunities. The model is also used to estimate the associated greenhouse gas (GHG) emissions.

Local energy transition processes are complex socio-technical transitions requiring careful study. The use of System Dynamics (SD) in modelling and analyzing local energy transitions is especially suitable given the characteristics of SD. Our aim is to systematically categorize the different ways SD is used and useful to scrutinize local energy transitions, and to see if we can discern any common themes that can be useful to researchers looking to scrutinize local energy transitions, using SD. The study is exploratory in nature, with peer-reviewed journal and conference articles analyzed using content analysis. The six categories on which the articles are analyzed are: the sector the article studies; the transition that is studied in the article; the modelling depth in the article; the objective of the article; the justification for using SD provided in the article and the levels of interaction with 'local'. Our findings show most of the local energy transitions have been studied using simulatable Stock and Flow Diagrams in SD methodology. The important sectors in the energy field are represented in terms of SD modelling of local energy transitions, including electricity, transport, district heating etc. Most of the local energy transitions scrutinized by SD in the articles have descriptive objectives, with some prescriptive, and just one evaluative objective. In terms of justification for using SD provided by the articles analyzed in this study, we found four major themes along which the justifications that were provided. They are dynamics, feedbacks, delays and complexity, systematic thinking, bridging disciplines and actor interactions and behaviour. The 'dynamics, feedbacks, delays and complexity' theme is the most cited justification for the use of SD in scrutinizing local energy transitions, followed by systematic thinking.

In this paper, potential natural gas and renewable natural gas supply pathways and natural gas vehicles (NGVs) have been selected and evaluated with regards to well-to-wheel energy expended, greenhouse gas (GHG) emissions, and regulated (air pollutant) emissions. The vehicles included in the evaluation are passenger cars, light-duty vehicles (LDVs), and heavy-duty vehicles (HDVs) for road-transport applications, and a short-range passenger vessel for maritime transport applications. The results show that, compared to conventional fuels, in both transport applications and for all vehicle classes, the use of compressed and liquefied natural gas has a 15–27% GHG emissions reduction effect per km travel. The effect becomes large, 81–211%, when compressed and liquefied renewable natural gas are used instead. The results are sensitive to the type and source of feedstock used, the type of vehicle engine, assumed methane leakage and methane slip, and the allocated energy and environmental digestate credits, in each pathway. In maritime applications, the use of liquefied natural gas and renewable natural gas instead of low sulfur marine fuels results in a 60–100% SOx and 90–96% PM emissions reduction. A 1% methane slip from a dedicated LNG passenger vessel results, on average, in 8.5% increase in net GHG emissions.

The rapid growth in Tree Planting for Fuelwood (TPF) program indicates the importance of taking care of the increasing demand for fuelwood globally. TPF programs in Tanzania aim to sustainably meet the rising demand for fuelwood. We evaluate the impact of TPF programs on the number of trees planted and those planted for fuelwood. Using survey data, we employ the Heckman and Propensity Score Matching techniques to estimate whether households plant trees for fuelwood and can identify tree species that would influence them to plant trees. We find positive and significant impacts of TPF programs on the number of trees planted and those planted for fuelwood. Households who participated in TPF programs have significantly more trees than their counterparts. Furthermore, we observed a positive and significant influence of TPF programs on forest policy in terms of harvesting tree products for trade, household assets, farm size, household head's age, tree species and income from selling fuelwood. Although the forest policy on harvesting is associated with households' participation in TPF programs, in practice there is no freedom to harvest and transport tree products obtained from farms, and both fuelwood from farms or natural forests both face restrictive transport tariffs. The results further indicate that households plant trees mainly to sell fuelwood. These results can be used by policymakers to promote tree planting on farms to obtain an income from fuelwood, treating it as a business opportunity. This paper makes a significant contribution to the literature due to the approaches used for estimation. Our results also suggest that fuelwood which receives less attention when it comes to sustainable energy production may need a regulatory authority like petroleum, natural gas and electricity which are regulated by the energy authority in Tanzania.

With increasingly improved cooking stoves (ICS) that aim to reduce fuelwood consumption by forest-dependent households, more evidence of what drives households to adopt ICS is needed. Using data from a representative sample (N=271) of households in a rural part of eastern Tanzania, we estimated a mixed logit model to take into account the limitations of the standard multinomial logit model and relaxed the restrictive assumption of the conditional logit model. The experiment results show a strong correlation between payment mechanisms and adoption of ICS. We also found interesting results that households provided with just one type of ICS adopted it less (30%). On the other hand, households supplied with more than one type of ICS largely adopted it (48%). In addition, the ICS that uses both charcoal and firewood was purchased by most households (80%), which raised the total uptake of ICS to 48 %. These results also provide empirical evidence of a shift from consuming firewood for energy to charcoal in rural areas. The study suggests that any efforts to promote ICS should seriously consider offering rural households a choice of ICS as opposed to a single type, inducing suppliers of ICS to extend them on credit, and offering ICS for cash at harvest time, as their cash flow depends on seasonal income from agricultural activities.

Mini-grids are seen as an important option for increasing access to electricity in non-electrified rural areas where grid-extension is unfeasible. Appropriately dimensioning and constructing mini-grids requires knowledge of electricity usage. There is currently a lack of measured load profiles from mini-grids and the most common method for estimating electricity usage is through appliance data collected via interviews. Thus, this paper compares and investigates the differences between measured daily load profiles and daily load profiles created from appliance data collected through interviews and how the two methods impact the dimensioning and operation of a mini-grid. This is done by comparing load profiles for an entire mini-grid, a household and SME customers with large loads. The paper reports differing results from the two methodologies. Generally, the results show that the interview-based load profiles fail to provide an accurate overall estimate. The calculated performance metrics for the two methods also shows large differences. The interview-based load profiles mainly fail to provide accurate estimates of energy and the energy related (capacity factor and load factor) performance metrics. Accordingly, the implications for mini-grid operators and developers could be significant. The interview-based load profiles indicate the mini-grid system to be considerably less technically and economically desirable than measurements show. Suggestions for how the interview process can be improved are presented.

While forests are a primary source of energy for the majority of Tanzanian households, the forest cover is rapidly declining. The Tanzanian government has introduced a tree-planting campaign strategy, aimed at reducing pressure on natural forests. However, the campaign appears not to have contributed significantly to the forest recovery rate. Thus, this study aims at examining household perceptions of tree-planting for wood energy production for both in-house uses and for sale, and identify the factors influencing household perceptions of tree-planting. We employed the multinomial logit model to analyse the factors influencing household perceptions of tree-planting for energy. Our findings indicate that respondents considered the right/freedom to harvest trees from farms and transport them to markets as the most important factor (86%), followed by lack of awareness of tree-planting programmes (72%), and the existence of fuelwood for free from natural forests (59%). The size of the farm, education, distance to forest reserves, and age of the household head are found to have significant impact on the household perceptions of tree-planting for energy. Our results further show that woodfuel harvesting and enforcement systems do not exist in nearby forests. This situation is exacerbated by the absence of a specific policy formulated to match with the daily demand of forest produce for energy and income of households near forest reserves. Thus, we suggest policy makers to target policies and actions promoting tree-planting for energy.

Construction of new low-energy buildings (LEB) areas is attracting attention as a climate mitigation measure. Heat can be supplied to buildings in these areas through individual solutions, through a small, on-site heat network, or through a heat connection to a close-by district-heating (DH) system. The choice between these options affects the energy supply systems and their carbon emissions far beyond the LEB area. We compare the long-term systems impacts of the three heat-supply options through dynamic modelling of the energy systems. The study draws on data collected from a real LEB area in Sweden and addresses scale-dependent impacts on district heating systems. The results show that, generally, the individual and on-site options increase biomass and electricity use, respectively. This, in turn, increases carbon emissions in a broader systems perspective. The systems impacts of the large heat network option depend on the scale and supply-technologies of the DH system close to the LEB area.

Sulphur dioxide (SO2) emissions cause acidification and human health problems which are, despite present policy instruments, projected to remain even after 2030 in Europe. Additional instruments are needed to solve the problems, and impact analysis of already used policy instruments would contribute to the development of new effective instruments. We present a study on how much of the decoupling of SO2 emissions from economic growth 1990–2012 that was due to SO2 policy instruments in general and to what extent it is possible to estimate the impact of individual instruments. Focus is on Sweden, a country with problems reaching its SO2-related environmental policy targets and with detailed data available. We applied decomposition analysis combined with an analysis of the chronological development of emission factors and mandated emission limits. Our use of official emission inventory data and publicly available data on the development of SO2 policy instruments increase the usefulness of our results to policy makers. The results indicate that at least 26–27% (corresponding to ∼35–36 ktonne annually) of the decoupling 1990–2012 was due to SO2 policy instruments. 4–5% (∼6–7 ktonne) of the decoupling was caused by one environmental permit decision and stricter sulphur emission limit for marine oils. Most of the total impact of SO2 policy instruments could not be causally connected to an individual instrument, because many events and developments overlap in time. The implications of the results are that: a) SO2 policy instruments should still be important to reduce SO2 emissions in many countries; b) a lower boundary total emission impact of SO2 policy instruments can be estimated, but with current knowledge and data the impacts of individual instruments are rarely possible to estimate. Research on how to increase the precision in total impact estimates of SO2 policy instruments is needed to improve future impact analyses. More detailed emission inventory data would improve impact analysis of individual instruments.

The high oil dependence and the growth of energy use in the transport sector have increased the interest in alternative nonfossil fuels as a measure to mitigate climate change and improve energy security. More ambitious energy and environmental targets and larger use of nonfossil energy in the transport sector increase energy–transport interactions and system effects over sector boundaries. While the stationary energy sector (e.g., electricity and heat generation) and the transport sector earlier to large degree could be considered as separate systems with limited interaction, integrated analysis approaches and assessments of energy–transport interactions now grow in importance. In recent years, the scientific literature has presented an increasing number of global energy–economy future studies based on systems modelling treating the transport sector as an integral part of the overall energy system and/or economy. Many of these studies provide important insights regarding transport biofuels. To clarify similarities and differences in approaches and results, the present work reviews studies on transport biofuels in global energy–economy modelling and investigates what future role comprehensive global energy–economy modelling studies portray for transport biofuels in terms of their potential and competitiveness. The results vary widely between the studies, but the resulting transport biofuel market shares are mainly below 40% during the entire time periods analysed. Some of the reviewed studies show higher transport biofuel market shares in the medium (15–30 years) than in the long term (above 30 years), and, in the long-term models, at the end of the modelling horizon, transport biofuels are often substituted by electric and hydrogen cars.

Recently, the government of Ethiopia has been shaking up the power industry by introducing reforms with the hope of increasing electricity access, ensuring resource adequacy, stimulating private investment and guaranteeing financial sustainability of the sector. Restructuring of utility, liberalizing energy market, tariff revision, targeting universal access, and export market are some of the sea changes undertaken by the government. The expected return from these reforms is very high, sometimes to a level that it looks too good to be true. The study thus evaluates the effectiveness of the reforms by assessing the future generation adequacy in contrast to the growing electricity demand. An analytical method to calculate resource planning indices such as reserve margin and expected unserved energy is used. The results show that the Ethiopian power system will face about 10 TWh energy shortage in the near-future. The study begins by providing an overview of the power sector and the recent reform activities with their intentions and goals. The result of the study could be important as input for making policy-adjustments and/or revamping implementation strategies.

Use of bioenergy can contribute to greenhouse gas emission reductions and increased energy security. However, even though biomass is a renewable resource, the potential is limited, and efficient use of available biomass resources will become increasingly important. This paper aims to explore system interactions related to future bioenergy utilization and cost-efficient bioenergy technology choices under stringent CO2 constraints. In particular, the study investigates system effects linked to integration of advanced biofuel production with district heating and industry under different developments in the electricity sector and biomass supply system. The study is based on analysis with the MARKAL_Sweden model, which is a bottom-up, cost-optimization model covering the Swedish energy system. A time horizon to 2050 is applied. The results suggest that system integration of biofuel production has noteworthy effects on the overall system level, improves system cost-efficiency and influences parameters such as biomass price, marginal CO2 emission reduction costs and cost-efficient biofuel choices in the transport sector. In the long run and under stringent CO2 constraints, system integration of biofuel production has, however, low impact on total bioenergy use, which is largely decided by supply-related constraints, and on total transport biofuel use, which to large extent is driven by demand.

In this paper, in the light of national targets of a fossil independent future Danish energy system, cost-effective deep decarbonisation solutions in transportation have been explored under base-, alternative technical-, and policy scenarios in the TIMES modelling environment. The TIMES-DK model was further developed to concurrently represent all emerging transport technologies (ETTs) in road- and off-road transport applications, disaggregated transport technologies and service demands segmentation to capture consumers preferences and heterogeneity, and to endogenise fuel infrastructures. The model runs optimise the societal surplus in between 2010 and 2050. There is a particular focus on the role of gas in transport. The results reveal that in between 2020 and 2040, natural gas (NG) could cost-efficiently serve as a transition fuel. Decarbonisation pace and fuel infrastructure assumptions were found to have a large impact on the NG adoption levels. This study showed that the combined use of liquid biofuels (mainly biomethanol), upgraded biogas, electricity, and hydrogen fuels would deliver cost-effective deep decarbonisation by 2050; however, their various decarbonisation roles vary within and across transport segments. Depending on the decarbonisation pace, a marginal CO2 abatement cost of 419–549 €/ton (or 1–1.29 €/L gasoline) is required by 2050 in Denmark. The results also showed that 25% and 30% cost reductions of BEVs and hydrogen fuel cell vehicles (HFCVs), compared to our central cost assumptions, would increase their respective adoption by 36% and 66% towards 2050. They show high market shares particularly in the medium size segment than in the small and large segments. Competition for limited biomass resources coupled with higher fuel demand results in adoption of ETTs.

The adoption of electric vehicles (EV) is effectively a problem of socio-technical transitions and comes with its complexities. The Thai Energy Efficiency Development Plan includes the adoption of EV as a voluntary measure to increase the energy effectiveness of its transport sector and to mitigate GHG emissions. But, there are other important social, technological, economic and policy factors which need to be thoroughly investigated before the EV transition is attempted in Thailand, since the environmental cost may outweigh the benefits of the EV transition. The methodology used is based on systems thinking and called Causal Loop Diagrams (CLD). In CLD, the factors underpinning the benefits accruing from the EV transition in Thailand are characterized as causal relationships and feedback loops. Preliminary CLD investigation into the factors for EVs show the technological factor EV efficiency levels and their cost (economic factor) are important in determining the GHG reduction benefit, along with the grid emission factor.

Co-creation in the societal sphere is becoming important in many parts of the world. However, empirical analysis of co-creation in local energy transitions has been understudied. This paper aims to contribute to the field of local energy transitions by integrating a model-based approach with the municipal co-creation efforts in a local energy transition setting. The study uses a mixed-methods approach, with both quantitative and qualitative methods underpinning the approach. A System Dynamics (SD) model is built to analyse the feedback loops created by the co-creation efforts of the municipalities in Sk&aring, ne, Sweden to increase the uptake of household solar photovoltaics. Simultaneously, the model is conceptualized and built in coordination with the municipality actors, and qualitative validation provided by them. An iterative process is implemented, consisting of three steps: interaction with the municipality actors (MAs), developing the causal relationships between the model variables and model development. The suggestions and discussions with the MAs were very useful in understanding the social factors and processes which help in the diffusion of a technologically innovative product, such as solar PV. The MAs said that they found the explanation of the modelling variables useful in undertaking the co-creation efforts.

The transition from high carbon-intensity to low carbon-intensity transport fuels entails the development of energy efficient and cost-effective decarbonisation pathways. In this paper, 14 potential natural and renewable gas supply pathways and natural gas vehicles (NGVs) have been selected and evaluated with regards to well-to-tank (WTT) fuel production costs and break-even vehicle added investment costs. NGVs are evaluated for both road- and maritime transport applications with three types of gas engines; dedicated, dual fuel, and high pressure direct injection (HPDI) engines. The results indicate that owing to the alternate gas distribution mechanisms and filling stations configuration there exist a substantial fuel production cost differences between the selected gas pathways. Despite its long-distance shipping and distribution, imported LNG showed significant production cost advantage over compressed natural gas (CNG) and liquefied renewable natural gas (LRNG) pathways. Evaluating the current economic performances, all NGVs are found to be competitive corresponding to gasoline cars, but not compared to diesel cars due to the lower price gap between CNG and diesel. In the heavy-duty vehicle and passenger vessel segments, however, owing to the high price gap between LNG and diesel/marine gas oil (MGO), all NGVs and LNG passenger vessels showed high competitiveness compared to their conventional counterparts.

Biogas has emerged as a promising renewable technology to convert agricultural, animal, industrial and municipal wastes into energy. Biogas development can be integrated with strategies to improve sanitation as well as reduce indoor air pollution and greenhouse gases. Currently, the total biogas production in India is 2.07 billion m(3)/year. This is quite low compared to its potential, which is estimated to be in the range of 29-48 billion m(3)/year. Hence, this study aims to identify both technical and non-technological barriers impending biogas dissemination in India. Biogas dissemination is affected by various waste, renewable energy, and urban policies. Barriers were therefore identified individually for rural and urban biogas systems existing in India using decomposition analysis. The results show that type and importance of barriers vary strongly between biogas systems due to the difference in technology maturity, feedstock availability and quality, supply chain, awareness level and policy support.

Bioenergy could contribute both to the reduction of greenhouse gases and to increased energy security, but the extent of this contribution strongly depends on the cost and potential of biomass resources. For Sweden, this study investigates how the implementation of policies for CO2 reduction and for phase out of fossil fuels in road transport affect the future utilization of biomass, in the stationary energy system and in the transport sector, and its price. The analysis is based on the bottom-up, optimization MARKAL_Sweden model, which includes a comprehensive representation of the national energy system. For the analysis, the biomass supply representation of MARKAL_Sweden is updated and improved by the use of, e.g., forestry forecasting modeling and through construction of detailed biomass supply curves. A time horizon up to 2050 is applied. The results indicate a potential for significantly higher use of bioenergy. In the main analysis scenario, in which CO2 reduction of 80% by 2050 is imposed on the Swedish energy system, the total bioenergy utilization increases by 63% by 2050 compared to 2010. The largest increase occurs in the transport sector, which by 2050 accounts for 43% of the total primary bioenergy use. The high demand and strong competition significantly increase biomass prices and lead to the utilization of higher cost biomass sources such as stumps and cultivated energy forest, as well as use of pulpwood resources for energy purposes.

A widespread dissemination of improved cooking stoves in the developing world can lead to considerable improvement of health, to reduced pressure on natural woody resources and to substantial reductions of emissions contributing to global warming. A number of programs have aimed to achieve such dissemination, while few of the programs have had any large-scale success. It has been suggested that a more commercial approach, as opposed to subsidized or freely distributed stoves, would achieve a higher level of success. However, a majority of the households that would benefit from an improved stove are poor and cannot afford the cost of the stove, especially if no monetary savings are possible from a more efficient fuel use, i.e. , if the fuel used is collected biomass. The aim of this paper is to propose and evaluate a model that might overcome some of the barriers previous programs have experienced. The proposed model involves commercialization of collected fuels. The methods for evaluation include a qualitative assessment of the proposed model aided by the literature on improved cooking stove programs, fuel wood collection and fuel switching together with a quantitative simplistic model calculation of a hypothetical application of the proposed model principles, in order to assess its financial feasibility. The assessment indicates that the model would increase both households’ incentives and means to purchase and use improved cooking stoves. Furthermore, the model could possibly be partly financed based on carbon credits achieved from the reduction of greenhouse gas emissions.

First and second generation biofuels are among few low-carbon alternatives for road transport that currently are commercially available or in an early commercialization phase. They are thus potential options for meeting climate targets in the medium term. For the case of Sweden, we investigate cost-efficient use of biofuels in road transport under system-wide CO2 reduction targets to 2050, and the effects of implementation of targets for an almost fossil-free road transport sector to 2030. We apply the bottom-up, optimization MARKAL_Sweden model, which covers the entire Swedish energy system including the transport sector. For CO2 reductions of 80% to 2050 in the Swedish energy system as a whole, the results of the main scenario show an annual growth rate for road transport biofuels of about 6% from 2010 to 2050, with biofuels accounting for 78% of road transport final energy use in 2050. The preferred biofuel choices are methanol and biomethane. When introducing additional fossil fuel phase-out policies in road transport (−80% to 2030), a doubling of the growth rate to 2030 is required and system CO2 abatement costs increases by 6% for the main scenario. Results imply that second generation biofuels, along with energy-efficient vehicle technologies such as plug-in hybrids, can be an important part of optimized system solutions meeting stringent medium-term climate targets.

Despite the considerable efforts spent on village electrification schemes in India, there is a general lack of evaluation of impacts, successes and of failures. A case study in Chhattisgarh state in India has been carried out to assess what effect village electrification through solar power has had for the beneficiaries and whether technical and maintenance factors provide for the desired results set by Indian rural electrification policy. Consequences for the beneficiaries have been investigated through a field survey conducted in eleven villages with 158 respondents, maintenance factors have been investigated through interviews with engineers and operators, and technical factors through analysis of electricity output from micro-grids. In villages where the systems had been installed in the past two years, children studied on average 41 min more in the evenings, more than twice as much as before electrification. Dinner cooking commenced on average 36 min later, a sign of higher flexibility of time use and thus of women's empowerment. Furthermore, the median household monthly kerosene use decreased by 2 l, or 67%, but commercial productive activities were found to be limited. 75% of the 69 micro-grid power plants evaluated were found to have too little output to supply for the stated 6 h of daily light per household, and the capacity installed per household decreased with village size. Plant capacity factors were found to vary greatly, most likely an effect of poor installation and/or inferior components. A tendency to replace energy-saving lights with incandescent lights requiring more power per lumen was found, leading to a decrease in obtainable light output.

The current utilisation of biogas from anaerobic digestion is low compared to the technical potential. This study investigates requirements for policy support to overcome techno-economic barriers of biogas utilisation and effects of different biogas distribution strategies. Two potential sectors for biogas use are covered: the transport sector and the district heating sector. A quantitative, optimising, energy system modelling approach is applied and the region of Vastra Gotaland, Sweden, is studied. The model has a high geographical resolution and locations of both biogas feedstock and potential markets are taken into account. The results show that a small part of the technical biogas potential can be cost-effectively utilised without biogas subsidies or larger infrastructural investments. Comparably low subsidies give significant increases in cost-effective biogas utilisation levels, but utilisation close to the full technical potential is linked to high subsidies. From a techno-economic perspective, biogas is best used as vehicle gas. Since local vehicle gas markets are limited, enhanced biogas distribution conditions not only imply larger total cost-effective biogas utilisation, but also a larger share of biogas as vehicle gas. Compared to distribution strategies based on truck transports and regional biogas grids, an expanded natural gas grid presents possibilities but also risks.

Heat load variations, daily as well as seasonal, are constraining co-generation of high-value energy products as well as excess heat utilisation. Integration of heat-driven absorption cooling (AC) technology in a district heating and cooling (DHC) system raises the district heat (DH) demand during low-demand periods and may thus contribute to a more efficient resource utilisation. In Sweden, AC expansion is a potentially interesting option since the cooling demand is rapidly increasing, albeit from low levels, and DH systems cover most of the areas with potential cooling demand. This study aims to assess the potential for cost and CO2 emission reduction due to expansion of DH-driven AC instead of electricity-driven compression cooling in the DHC system of Goteborg, characterised by a high share of low-cost excess heat sources. The DHC production is simulated on an hourly basis using the least-cost model MARTES. Despite recent advances of compression chillers, the results show potential for cost-effective CO2 emission reduction by AC expansion, which is robust with regards to the different scenarios applied of energy market prices and policies. While the effects on annual DHC system results are minor, the study illustrates that an increased cooling demand may be met by generation associated with low or even negative net CO2 emissions – as long as there is high availability of industrial excess heat in the DHC system, or if e.g. new biomass-based combined heat and power capacity is installed, due to the avoided and replaced marginal power generation.

Several technology and fuel options could be used to lower the strong oil dependence of the transportation sector. To formulate policies and to cost-effectively meet oil reduction objectives, assessments and comparisons of the long-term economic performances of different technology trajectories are essential. In this work, the energy and technology costs associated with reducing oil consumption in passenger cars in Sweden are calculated for a number of possible future transport fuel pathways and for different energy prices and climate policies. An optimisation model is applied in a simulatory multiple-run approach for this purpose. The model encompasses the transportation sector, as well as the stationary energy system. In terms of results, a methanol-based pathway gives incremental system costs in the range of − 0.9–3 billion EUR for a complete phase-out of passenger car oil up to 2030. As compared to the methanol pathway, other biomass gasification-based fuel pathways involve additional incremental system costs in the region of 3 billion EUR, whereas ethanol- and electricity-based pathways give additional incremental system costs of 4–5 billion EUR. At lower oil reduction levels, the cost differences between the pathways are smaller and the electricity-based pathway is significantly more cost-competitive.

External cost (XC) accounting of air pollution has been applied in a number of energy system studies in order to find least-cost solutions from a social-cost perspective. In these studies, the economic evaluation covers the XCs apart from the private costs. The greater number of life cycle processes, pollutants and environmental impacts covered, the more accurate the results will be but, obviously, the XC accounting process will be more complex and time-consuming. There is also the risk of increasing uncertainty as complexity increases, and the question is to decide on the appropriate level of comprehensiveness. The purpose of this paper is to evaluate certain simplified XC accounting approaches applied to a study of the district-heating (DH) system of Gothenburg, Sweden. The methodology applied is to vary the inclusion of pollutants and life cycle processes in the XC accounting under different scenarios. The results show that if environmental costs are estimated to be substantial and the net power generated in the DH system is assumed to replace generation in coal-fuelled power plants, limiting the coverage of life cycle processes and pollutants outside the DH system would not be appropriate. Instead, if assuming that power generation based on natural gas were replaced, the application of all simplified approaches studied leads to DH solutions that are congruent with those obtained employing a more comprehensive approach and is, thus, considered to be sufficient. However, results also show that certain simplified approaches are justified regardless of the assumed power generation replacement and given a wide range of environmental cost estimates used in the study, such as limiting the number of covered pollutants to the most relevant ones (CO2, SO2 and NOx). Thus, a less comprehensive XC accounting process may be considered appropriate for finding least social-cost solutions in the Gothenburg DH system, as well as potentially in many other DH systems featuring similar technical and environmental performance.