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Industrial process heat (IPH) uses nearly three-quarters of U.S. manufacturing sector fuel energy, with most of IPH powered by fossil fuel combustion. Appreciably reducing industrial CO2 emissions will necessarily involve addressing IPH demand. Solar photovoltaics (PV) have contributed to the changing fuel mix of electricity generation in the United States, but on-site use of solar energy in the manufacturing sector remains insignificant. To understand the economic feasibility of IPH fuel switching, we develop an open-source process parity framework to identify conditions when solar process heat technologies can reach cost parity with an incumbent fossil fuel combustion technology. Building a case study that reflects common IPH demands and applicable solar technologies across several locations in the United States, we generalize the relationship between key parameters of solar resource, investment and fuel prices. We evaluate the use of solar thermal (ST) and PV connected electric boilers to partially substitute natural gas boilers in a brewery. Cost parity is not achieved in any analysis location for current solar system costs and fuel prices. Los Angeles County is most likely to achieve cost parity due to the higher fuel prices compared to other counties.

Energy-intensive industries are difficult to decarbonize. They present a major challenge to the emerging countries that are currently in the midst of rapid industrialization and urbanization. This is also applicable to Japan, a developed economy, which retains a large presence in heavy industries compared to other developed economies. In this paper, the results obtained from four energy-economic and integrated assessment models were utilized to explore climate mitigation scenarios of Japan's industries by 2050. The results reveal that: (i) Japan's share of emissions from industries may increase by 2050, highlighting the difficulties in achieving industrial decarbonization under the prevailing industrial policies; (ii) the emission reduction in steelmaking will play a key role, which can be achieved by the implementation of carbon capture and expansion of hydrogen technologies after 2040; (iii) even under mitigation scenarios, electrification and the use of biomass use in Japan's industries will continue to be limited in 2050, suggesting a low possibility of large-scale fuel switching or end-use decarbonization. After stocktaking of the current industry-sector modeling in integrated assessment models, we found that such limited uptake of cleaner fuels in the results may be related to the limited interests of both participating models and industry stakeholders in Japan, specifically the interests on the technologies that are still at the early stage of development but with high reduction potential. It is crucial to upgrade research and development activities to enable future industry-sector mitigation as well as to improve modeling capabilities of energy end-use technologies in integrated assessment models. [ABSTRACT FROM AUTHOR]

An extended Kaya identity and the Logarithm Mean Divisia Index approach were applied in this paper to identify, quantify and explain the main factors behind Cameroon's CO2 emissions before, during and after the economic crisis of the years 1980. The analyses covered the period from 1971 to 2014 and the results showed that: (1) Cameroon's carbon intensity increased by 75 and 47% during the periods before (1971–1984) and after (1984–1994) the economic crisis, while it decreased significantly by − 135% during the crisis period (1994–2014). At the same time, the country's emission factor increased by 30% between 2007 and 2014. (2) The effect of the demographic change was the main driver of Cameroon's CO2 emissions during the periods 1984–1994 and 1994–2014, whereas the effect of economic activity was the main driver of the increase in these emissions between 1971 and 1984. (3) The energy intensity effect contributed to the increase in CO2 emissions during the period 1984–1994 in the same way as the effect of demographic change. However, this factor helped reduce CO2 emissions in the other two periods. (4) Although the effect of substitution of fossil fuels and the effect of renewable energy all contributed to reducing CO2 emissions during the period of this study, we found that the effect of renewable energy behind CO2 emissions remains insignificant compared to the renewable energy potential available in Cameroon. Finally, policy recommendations aimed at enabling Cameroon to achieve its objectives of reducing CO2 emissions were formulated in this article. [ABSTRACT FROM AUTHOR]

Since January 1, 2018, ships berthed at all ports of the three designated emission control areas (ECAs) in China are required to use fuel with sulfur content not exceeding 0.5% (m/m), excluding one hour postarrival and one hour predeparture. To understand changes in SO2 due to this policy, two observation stations were established on Waigaoqiao Dock in the Yangtze River estuary. Three data types were collected from March 2018 to May 2018, namely, wind speed and direction, SO2 concentration, and ships' arrival and departure times. The statistics indicate that the wind direction changed little during the observation period and SO2 concentration was below 5 µg/m3 77.47% of the time. Meanwhile, ships' arrival and departure at the dock had a distinct influence on overall SO2 distribution, including occurrence of concentrations ≥5 µg/m3. The three types of data were divided into six groups and a difference-in-difference model was used for analysis. The result shows that SO2 concentration increases due to the use of high-sulfur fuel and is especially significant when the wind is southwesterly. Furthermore, there was a positive correlation between increases in SO2 concentrations over 5 µg/m3 and the number of ships arriving or departing from the port. This study reports the positive impact of fuel switching on air quality and can be used to evaluate adherence to the ECA policy. [ABSTRACT FROM AUTHOR]

Consumption of energy is a determinant of the socioeconomic status of many citizens across the globe. The majority of rural households in India are dependent on biomass fuels. Existing data on the factors affecting fuel switching in rural India are insufficient to analyze a behavioral change among families. This paper evaluates the influence of four variables income, education, cost of fuel, and clean fuel supply on fuel adoption decisions. To understand the study population's behavioral change, a Household Survey is conducted in 20 villages (in India's rural district). Along with field observation, data are also collected on energy usage at the household level using a formal questionnaire. Binary logistic regression is applied to establish a link between the variables. Both biomass fuels and Liquefied Petroleum Gas are used mostly for cooking. The prevalence of energy stacking behavior is observed even among middle and upper‐income families. Modest evidence for the "energy ladder" hypothesis is seen, however, a "switch over" to cleaner fuels is not. [ABSTRACT FROM AUTHOR]

• Household fuel choices are rooted in their income, fuel access and occupation. • Socio-cultural traditions influence the choice of cooking fuel. • Reliable power supply unlocks the latent demand for cleaner fuel in rural areas. • Targeted and consistent policies form the pace and trajectory of energy transition. Multiple fuel use, incorporated within the concept of fuel stacking is prevalent in households at the beginning and mid-way in their ascension up the energy ladder. However, households cannot fully let go of their traditional energy sources presenting inherent policy complexities and contradictions within energy transition theories. Empirical insights into the determinants of clean energy transitions are presented that highlight the need to recognise both fuel switching and stacking occurs in many rural households. It focuses on rural communities in India and illuminates policy dilemmas. The study reveals that fuel stacking is likely to remain a key part of the socio-cultural energy tradition that will impact progress towards low carbon and a cleaner energy transition. We therefore argue targeted policy interventions, multi-stakeholder collaboration and strong energy governance is needed to incorporate socio-cultural traditions particularly linked to cooking. This suggests new energy policy that must offer flexibility in order to achieve the twin goals of universal energy access and decarbonising energy systems. [ABSTRACT FROM AUTHOR]

The reduction in energy and emissions from the building sector can come from improved standards for new construction and retrofits to existing buildings. The retrofit viability for single-detached homes in Vancouver, Canada, is examined in terms of the key drivers and barriers involving economic and social forces. Local experts considered the likelihood of retrofits occurring to several archetypal dwellings that were synthesized from local building data and homeowner characteristics. The survey results (n = 56) raised less known but potentially significant issues regarding energy-efficiency retrofits in Vancouver. Domestic fuel switching, from fossil fuel energy services to electricity, is likely the most desirable future mechanism for decarbonizing homes. However, many of the respondents identified that Vancouver's real estate market has a significant negative influence on retrofitting due to high land values, which results in a high demolition rate of existing homes. Only 46% of responses returned a view that an existing home would remain standing by 2050. In addition, 41% of responses expressed a doubt that the dwelling, whether existing or new, would achieve carbon neutrality by 2050. Both issues confront the City of Vancouver's current emissions reduction planning, which has targeted nearcomplete decarbonization of the residential building stock by 2050. [ABSTRACT FROM AUTHOR]

Energy production based on fossil fuels is the main reason for global warming. Many countries have begun switching fossil fuels with renewable energies, reducing the effects of climate change. A tremendous potential in future energy needs plays the Marine Renewable Energies (MRE). The MRE industry should take into consideration the potential environmental effects and if it poses any risks to marine animals, surrounding habitats or ecosystem processes. This research provides some insights regarding the MRE development and points out the potential environmental effects of implementing them and finally, draws some lines regarding the ecological effects of the MRE extraction from the Black Sea. [ABSTRACT FROM AUTHOR]

Economic growth in Asia has increased in the past three decades and has heightened energy demand, resulting in rising greenhouse gas emissions and severe air pollution. To tackle these issues, fuel switching and the deployment of renewables are essential. In the present paper, we discuss the environmental regulations, mainly carbon pricing, implemented in Asia and discuss their achievements. Empirical studies using microdata have shown that carbon pricing in Asia can reduce carbon emissions by promoting energy efficiency. At the macro level, we observe some evidence of fuel switching from coal to natural gas among major emitters. However, more carbon pricing is necessary in Asia if we aim for the decarbonization of the economy. [ABSTRACT FROM AUTHOR]

In order to achieve the temperature goals of the Paris Agreement, the world must reach net‐zero carbon emissions around mid‐century, which calls for an entirely new energy system. Carbon pricing, in the shape of taxes or emissions trading schemes, is often seen as the main, or only, necessary climate policy instrument, based on theoretical expectations that this would promote innovation and diffusion of the new technologies necessary for full decarbonization. Here, we review the empirical knowledge available in academic ex‐post analyses of the effectiveness of existing, comparatively high‐price carbon pricing schemes in the European Union, New Zealand, British Columbia, and the Nordic countries. Some articles find short‐term operational effects, especially fuel switching in existing assets, but no article finds mentionable effects on technological change. Critically, all articles examining the effects on zero‐carbon investment found that existing carbon pricing scheme have had no effect at all. We conclude that the effectiveness of carbon pricing in stimulating innovation and zero‐carbon investment remains a theoretical argument. So far, there is no empirical evidence of its effectiveness in promoting the technological change necessary for full decarbonization. This article is categorized under:Climate Economics > Economics of Mitigation [ABSTRACT FROM AUTHOR]

Shifting the energy mix of Nepal from the domination of traditional biomass followed by imported fossil fuel is a matter of urgency to drive the nation towards a low carbon and self-energy reliance economy. The full deployment of economically viable wind energy can be instrumental in increasing the share of renewable energy. The objective of this paper is to analyze economic viability of wind energy in different parts of Nepal based on the data from twelve research sites, four case study sites and the Global Wind Atlas dataset. The research found that viability of wind energy is high in high mountains, mid hill river corridors/valleys. Full capitalization of wind energy reduces the use of 0.31million kl fossil fuel annually, substitutes about 6.8% of annual import of petroleum fuel, avoids 4.5 million tons of CO2 emission annually and increases independency in energy supply in the country. The financial surplus generated due to petroleum fuel import substitution and investment grant reduction will be sufficient in producing 1082MW wind energy. Based on a cost benefit analysis, the implementation of a suitable feed-in-tariff policy coupled with the scaled-up plan of wind energy is an appropriate policy for enhancing the viability of wind power generation in Nepal. [ABSTRACT FROM AUTHOR]

The approach of fossil fuel substitution requires alternative strategies in the progressing sector coupling of energy storage, distribution and conversion. Promising solutions are flexibly supply chain models of green and blue hydrogen which is fed into the natural gas network (HNG). Prerequisite for a successful implementation is the functional capability of end-use applications for which different volumetric hydrogen thresholds are documented in literature. A clear research gap is thereby evident for HNG fired medium-speed large-bore gas engines typical used for stationary power generation. For solving this problem, generic single cylinder tests with focus on operating window, NO x formation and hydro-carbon emissions have been carried out. The results are analysed and compared to available publications of HNG fired high-speed gas engines to derive general insights of the combustion characteristics. Under rising blending share, an in literature described, general shifting of the possible operating window and an increase of NO x formation are detected. In terms of unburned hydrocarbons, a NO x -neutral reduction potential through hydrogen blending is only visible under very lean operating conditions. This result deviates from expected literature values of high-speed engine setups. The experimental study demonstrates the NO x neutral combustion capability of medium-speed large-bore gas engines under 20% hydrogen admixture. • Hydrogen blending in future power generation has rising importance in island modes. • Detailed literature review in the field of H 2 -blended gas engines is presented. • H 2 /NG shifts the operating area and reduces THC emissions at very lean conditions. • NO x neutral 20% H 2 /NG combustion is experimental validated. [ABSTRACT FROM AUTHOR]

Heterogeneity is a theme acquiring more and more prominence in the energy economic literature from both a modelling and policy-making perspective. We show that useful empirical evidence on this subject can be obtained by applying a parsimonious multivariate cointegration analysis that makes use of the increasingly available time series data on energy demand. We find that there is substantial heterogeneity in the demand for fuels from UK firms belonging to different subsectors, with price and level of production having different degrees of importance in the fuel choice, and with evidence of both substitutability and complementarity between fuels. Moreover, we show that fuel demand for the industrial sector as a whole is considerably more elastic than most estimates presented in the literature, finding which has direct relevance for policies aimed at influencing industrial fuel consumption through fuel switching. [ABSTRACT FROM AUTHOR]

This work demonstrates the effect of tin (Sn) doping on the manufacturing, electrochemical performance, and carbon deposition in dry biogas-fuelled solid oxide fuel cells (SOFCs). Sn doping via blending in technique alters the rheology of tape casting slurry and increases the Ni/ScSZ anode porosity. In contrast to the undoped Ni/ScSZ cells, where open-circuit voltage (OCV) drops in biogas, Sn–Ni/ScSZ SOFC OCV increases by 3%. The maximum power densities in biogas are 0.116, 0.211, 0.263, and 0.314 W/cm2 for undoped Ni/ScSZ, undoped Ni/ScSZ with 3 wt% pore former, Sn–Ni/ScSZ and Sn–NiScSZ with 1 wt% pore former, respectively. Sn–Ni/ScSZ reduces the effect of the drop in the maximum power densities by 26%–36% with the fuel switch. A 1.28–2.24-fold higher amount of carbon is detected on the Sn–Ni/ScSZ samples despite the better electrochemical performance, which may reflect an enhanced methane decomposition reaction. • Effect of Sn addition with blend in doping method to tape slurry, green tape, and cell's porosity in SOFC fabrication via tape casting route. • OCV increased by 3% in the Sn-NiScSZ cells while decreased by 7–12% in the undoped cells. • 1.28–2.24-fold higher amount of carbon detected on Sn-NiScSZ cells despite of 26–36% better electrochemical performance. [ABSTRACT FROM AUTHOR]

Cumulative emissions budgets are increasingly being used by decision-makers and analysts to understand emissions reductions and associated transitions in the context of long-term goals such as limiting global mean temperature increase over the century to 1.5 or 2 °C. While previous studies have explored the implications of such budgets for the global economy, few studies have conducted regional- and national-level analyses. This paper explores budgets through 2050 consistent with the 1.5 and 2 °C long-term temperature goals in the context of the USA. We employ a state-level model of the USA embedded within a global human-Earth system model (GCAM-USA) to study the implications of such budgets for the US energy system. Our results show that achieving the stringent budgets entails accelerated deployment of energy conserving technology, almost complete decarbonization of the power sector, increased electrification of buildings and industrial end-use sectors, and decarbonization of transport employing a combination of electrification and the substitution of fossil fuels for bioenergy. We also find substantial state-level differences in the relative roles of these decarbonization strategies. Furthermore, our results highlight that increased ambition in the near term will be valuable in setting the stage for smoother transformations in the future to achieve stringent budgets. [ABSTRACT FROM AUTHOR]

Compression ignition (CI) engines are widely used in modern society, but they are also recognized as a significative source of harmful and human hazard emissions such as particulate matter (PM) and nitrogen oxides (NOx). Moreover, the combustion of fossil fuels is related to the growing amount of greenhouse gas (GHG) emissions, such as carbon dioxide (CO2). Stringent emission regulatory programs, the transition to cleaner and more advanced powertrains and the use of lower carbon fuels are driving forces for the improvement of diesel engines in terms of overall efficiency and engine-out emissions. Ethanol, a light alcohol and lower carbon fuel, is a promising alternative fuel applicable in the dual-fuel (DF) combustion mode to mitigate CO2 and also engine-out PM emissions. In this context, this work aims to assess the maximum fuel substitution ratio (FSR) and the impact on CO2 and PM emissions of different nozzle holes number injectors, 7 and 9, in the DF operating mode. The analysis was conducted within engine working constraints and considered the influence on maximum FSR of calibration parameters, such as combustion phasing, rail pressure, injection pattern and exhaust gas recirculation (EGR). The experimental tests were carried out on a single-cylinder light-duty CI engine with ethanol introduced via port fuel injection (PFI) and direct injection of diesel in two operating points, 1500 and 2000 rpm and at 5 and 8 bar of brake mean effective pressure (BMEP), respectively. Noise and the coefficient of variation in indicated mean effective pressure (COVIMEP) limits have been chosen as practical constraints. In particular, the experimental analysis assesses for each parameter or their combination the highest ethanol fraction that can be injected. To discriminate the effect on ethanol fraction and the combustion process of each parameter, a one-at-a-time-factor approach was used. The results show that, in both operating points, the EGR reduces the maximum ethanol fraction injectable; nevertheless, the ethanol addition leads to outstanding improvement in terms of engine-out PM. The adoption of a 9 hole diesel injector, for lower load, allows reaching a higher fraction of ethanol in all test conditions with an improvement in combustion noise, on average 3 dBA, while near-zero PM emissions and a reduction can be noticed, on the average of 1 g/kWh, and CO2 compared with the fewer nozzle holes case. Increasing the load insensitivity to different holes number was observed. [ABSTRACT FROM AUTHOR]

A case study was conducted to evaluate the SO2 emission reduction in a power plant in Central Mexico, as a result of the shifting of fuel oil to natural gas. Emissions of criteria pollutants, greenhouse gases, organic and inorganic toxics were estimated based on a 2010 report of hourly fuel oil consumption at the "Francisco Pérez Ríos" power plant in Tula, Mexico. For SO2, the dispersion of these emissions was assessed with the CALPUFF dispersion model. Emissions reductions of > 99% for SO2, PM and Pb, as well as reductions >50% for organic and inorganic toxics were observed when simulating the use of natural gas. Maximum annual (993 µg/m3) and monthly average SO2 concentrations were simulated during the cold-dry period (152–1063 µg/m3), and warm-dry period (239–432 µg/m3). Dispersion model results and those from Mexico City's air quality forecasting system showed that SO2 emissions from the power plant affect the north of Mexico City in the cold-dry period. The evaluation of model estimates with 24 hr SO2 measured concentrations at Tepeji del Rio suggests that the combination of observations and dispersion models are useful in assessing the reduction of SO2 emissions due to shifting in fuels. Being SO2 a major precursor of acid rain, high transported sulfate concentrations are of concern and low pH values have been reported in the south of Mexico City, indicating that secondary SO2 products emitted in the power plant can be transported to Mexico City under specific atmospheric conditions. Implications: Although the surroundings of a power plant located north of Mexico City receives most of the direct SO2 impact from fuel oil emissions, the plume is dispersed and advected to the Mexico City metropolitan area, where its secondary products may cause acid rain. The use of cleaner fuels may assure significant SO2 reductions in the plant emissions and consequent acid rain presence in nearby populated cities and should be compulsory in critical areas to comply with annual emission limits and health standards. [ABSTRACT FROM AUTHOR]

The transportation sector is one of the main contributors to global greenhouse gas (GHG) emissions. As the efforts towards emission mitigation increase, the expectation from the sector arises equally. In this analysis, the transportation sector of Turkey is studied to shed light on the future based on historical realizations. In this respect, the Logarithmic Mean Divisia Index (LMDI) method is used to assess and reveal the influential factors on CO 2 emissions in the sector between 2000 and 2017. The emission intensity of the sector and fuel switching shows promising trends from 2000 through 2010, whereas growing preference for SUVs challenges emission reductions between 2010 and 2017. The results indicate that i) The transportation sector CO 2 emissions are mainly driven upwards by economic growth, followed by population and emission intensity effects from 2000 to 2017 ii) The overall impact of transportation intensity shows significant reduction potential iii) Fuel switching incentives and fleet efficiency have a positive effect on emission mitigation from 2000 through 2010. However, this gain is reduced due to the rising popularity of SUVs in the rest of the analysis period. In this respect, CO 2 emission mitigation in the transportation sector necessitates 1) careful planning of demand management for freight transportation including master designs production/manufacturing sites, material flows, and demand points coupled with economic activities 2) passenger transportation measures to reduce passenger car travel including zoning for public transit corridors, improved public transportation system 3) well-structured incentives on energy-efficient cars and clean energy technologies such as electric vehicles to convince individuals. Analysis can be generalized on a global scale due to the similar dynamics inherent in the sector. • The shift in transport modes results in a net emissions increase. • Abatement due to LPG use is not as much as expected. • A change in vehicle choices (shift to SUVs) started to overcome efficiency improvements. • There exists no significant emission reduction due to rail transport despite government investments. • Vehicle efficiency gains are successful at reducing emissions however, vehicle size preferences dampen the positive outcome. [ABSTRACT FROM AUTHOR]

Skeletal muscle is the largest metabolic organ in the human body and is able to rapidly adapt to drastic changes during exercise. Histone acetyltransferases (HATs) and histone deacetylases (HDACs), which target histone and non-histone proteins, are two major enzyme families that control the biological process of histone acetylation and deacetylation. Balance between these two enzymes serves as an essential element for gene expression and metabolic and physiological function. Genetic KO/TG murine models reveal that HDACs possess pivotal roles in maintaining skeletal muscles' metabolic homeostasis, regulating skeletal muscles motor adaptation and exercise capacity. HDACs may be involved in mitochondrial remodeling, insulin sensitivity regulation, turn on/off of metabolic fuel switching and orchestrating physiological homeostasis of skeletal muscles from the process of myogenesis. Moreover, many myogenic factors and metabolic factors are modulated by HDACs. HDACs are considered as therapeutic targets in clinical research for treatment of cancer, inflammation, and neurological and metabolic-related diseases. This review will focus on physiological function of HDACs in skeletal muscles and provide new ideas for the treatment of metabolic diseases. [ABSTRACT FROM AUTHOR]

This article examines the relationship between energy consumption, industrialization, urbanization, economic growth, and financial development in India from 1980 to 2017. The ARDL bound testing; Johansen & Juselius cointegration approach and Gregory & Hansen structural break cointegration technique confirm the long‐run relationship exists among variables. The result of long‐run analysis indicates that the industrialization, urbanization and economic growth play a vital role in increasing energy consumption in India. However, financial development indicates negative relation to energy consumption. The coefficient of error correction term is negative and statistically significant at 1% confidence level, it means last‐period's deviation from a long‐run equilibrium. It is clear from the results of Toda‐Yamamoto Causality, there is a unidirectional causality running from industrialization to energy consumption. However, there is bidirectional causality showing between energy consumption and urbanization, economic growth and energy consumption, and urbanization and Economic growth. Urbanization facilitates fuel switching, as decentralized rural energy sources like traditional wood‐burning are replaced by centralized energy sources. From the above findings, we argue that proper awareness should be made at the urban center regarding use of energy saving equipments and public infrastructure should be improved to harness the effect of urban agglomeration. As rapid development of energy intensive‐industries and economic activity in Indian economy, there is need of energy efficient technology in industry in order to reduce energy consumption. [ABSTRACT FROM AUTHOR]

Ghana is one of the few countries within the sub-Saharan region which has been successful in reducing energy poverty. However, ensuring energy security, affordability, and environmental sustainability remains a significant challenge for the future development of the sub-region. Here, we examine how the electricity supply can evolve into the future to meet potential emission obligations for the period of 2020–2040. A generation expansion planning model which is able to incorporate the reality of fuel shortages and fuel switching typical of a developing country's power system is used. In doing so, we generate a range of emission reduction costs that provide important benchmarks for the relatively under-studied sub-Saharan region and identify drivers of these costs specific to developing countries. Results indicate that the total discounted cost in expanding generation to meet the demand for all scenarios range from 13–17 billion US$, while the expected emission ranges from 99–189 mtCO 2. Subsequently, the cost of meeting different emission targets up to 2040 was quantified for each scenario ranging from 11–39 US$/tonne, which could be used as a benchmark for comparison in developed countries. We find that discount rates, representing Ghana's access to capital, are a particularly important variable for developing countries. We find that lower discount rates can lead to more investment in capital intensive renewable energy in the long run but can also lock in an additional conventional generation investment in the short term. Sensitivity analysis of demand growth reduction shows that with a 1% growth rate, the requirement of generation capacity could be reduced by 84%, providing initial evidence for the benefits of investing in demand-side measures. The study provides data and policy recommendations needed to inform decision-makers in developing countries as well as a comparison point for identifying decarbonization costs internationally. • A long-term MILP generation expansion planning model was developed. • The model handles unpredictability of energy policy using several scenarios. • Total discounted cost in meeting demand by 2040 ranged 13–17 billion US$. • The cost of meeting different emission targets is estimated and ranged 11–39 US$/tonne. [ABSTRACT FROM AUTHOR]

China's energy dependents on coal due to the abundance and low cost of coal. Coal provides a secure and stable energy source in China. Over-dependence on coal results in the emission of Hazardous Trace Elements (HTEs) including selenium (Se), mercury (Hg), lead (Pb), arsenic (As), etc., from Coal-Fired Power Plants (CFPPs), which are the major toxic air pollutants causing widespread concern. For this reason, it is essential to provide a succinct analysis of the main HTEs emission control techniques while concurrently identifying the research prospects framework and specifying future research directions. The study herein reviews various techniques applied in China for the selected HTEs emission control, including the technical, institutional, policy, and regulatory aspects. The specific areas covered in this study include health effects, future coal production and consumption, the current situation of HTEs in Chinese coal, the chemistry of selected HTEs, control techniques, policies, and action plans safeguarding the emission control. The review emphasizes the fact that China must establish and promote efficient and clean ways to utilize coal in order to realize sustainable development. The principal conclusion is that cleaning coal technologies and fuel substitution should be great potential HTEs control technologies in China. Future research should focus on the simultaneous removal of HTEs, PM, SOx, and NOx in the complex flue gas. Image, graphical abstract [ABSTRACT FROM AUTHOR]

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Abstract: Given the scale of carbon emissions in heavy clay manufacturing, the decarbonization of a ceramic production process cannot be limited to a fuel switch towards low- or non-carbon sources of process energy, but must include the removal of greenhouse gas (GHG) emissions caused by eventual decarbonization of raw materials. A different approach to raw materials is required as well. Carbon capture and storage (CCS), direct air capture (DAC), or carbon capture and usage (CCU) processes might become unavoidable even if these might have been deemed by industry to have limited viability due to the size and GHG dilution of a typical heavy clay installation. GHG management must become an essential part of the corporate strategies even for small or medium sized businesses. [ABSTRACT FROM AUTHOR]

Poverty, energy inequality and poor human health are interrelated issues. In India, around 625 million people do not have access to modern cooking fuels, and traditional fuels still provide 80–90% of the country's rural energy needs. For villages in and around forest areas that are dependent on fuelwood, this dramatically increases anthropogenic pressure on the forests. Such dependency adversely affects the health of the individuals using these traditional fuels, due to indoor air pollution, as well as the health of the surrounding environment, via forest degradation; it also increases incidences of human–animal conflict. Subsidies for liquefied petroleum gas (LPG) have been pivotal in shifting household preferences towards cleaner sources of energy. An analysis of 3124 households conducted for this study in the Chandrapur district, Maharashtra, India, in February 2018 revealed that apart from the income level of a household, other factors such as improving the education of women and reducing their distance traveled to obtain LPG refills should be looked at to improve LPG adoption rates. Building an efficient distribution network for LPG that reduces the distance traveled for refills is a key requirement for enhancing adoption of LPG The health benefits and environmental benefits emphasize that LPG is a public good, justifying its targeted subsidization for the marginalized population Affordability is a necessary, but not sufficient, condition for LPG adoption. Thus, increasing incomes does not lead to an autonomous switch to cleaner fuels. This underscores the need for promotion and awareness of using LPG Better education of women leads to higher adoption of LPG by the household [ABSTRACT FROM AUTHOR]

Household fuel substitution has been a crucial step for controlling air pollution in China, but the performance evaluation of household fuel substitution policies is overlooked. This study capitalized on the opportunity to use data collected during the household coal-replacement program in North China to evaluate the effect of a mandatory policy on fuel substitution at the micro-level. The results indicate that there is a significant effect of the coal-replacement program on fuel substitution, as we expected. The coal-to-electricity policy is effective in achieving the goal of a clean winter but not a warm winter due to the decline of delivered energy, while the high-quality coal replacement policy results in better performance in delivered energy but no improvement in indoor air quality. It is recommended to prioritize supporting measures on both the supply and demand sides before implementation, along with undertaking differential measures during the implementation phase to better address energy inequality. • China's coal-replacement program improves household energy structure. • Coal-to-electricity policy worsens delivered energy but improves indoor air quality. • Higher-quality coal replacement policy only achieves the goal of warm winter. • Mandatory fuel substitution should consider energy affordability and energy infrastructure. • Differential measures are needed to ameliorate the policies. [ABSTRACT FROM AUTHOR]

Alcohol blended with gasoline is generally termed as Gasohol. Gasohol fuel will reduce Carbon monoxide (CO), Nitrous oxide (NOx), Hydro carbon (HC) emissions and it will increase Carbon dioxide (CO2). The regulated and unregulated emissions raise with increase in the Ethanol percentage of the fuel. For the reduction of both regulated and unregulated emissions new catalyst (Vanadium Pentoxide/Cobalt oxide) were coated over the metal substrate of the conventional catalytic converter. The performance of Vanadium Pentoxide/Cobalt oxide coated Three-way catalytic converter (TWC) and emissions test on a single cylinder four stroke petrol engine was conducted on the both regulated and unregulated emissions. The recorded emissions results were compared with conventional and Vanadium Pentoxide/Cobalt oxide coated catalytic converter. The experimental results suggest that Vanadium Pentoxide/Cobalt oxide coated catalytic converter reduces 55%, 38% and 45% of HC, CO and NOx respectively. The reduction in unregulated emissions like acetaldehyde, acrolein, propionaldehyde and paraldehyde was reduced by 51%, 48%, 44% and 70% due to Three-way catalytic converter respectively. [ABSTRACT FROM AUTHOR]

The implications of national or regional energy policies for technical efficiency and environmental outcomes in electricity generation depend on fossil fuel input substitution. This study uses state level data to examine fossil fuel (coal and natural gas) substitution in electricity generation under increased availability of natural gas in the United States. We observe that changes in elasticities of substitution from pre-2009 to post-2009 differ across states suggesting that the effects of increased availability of inexpensive natural gas on electricity generation have been spatially heterogeneous. We rely on the observed heterogeneity to assess the effects of fossil fuel input substitution on technical efficiency and CO2 emissions. The results reveal that state level elasticity of substitution between natural gas and coal has a positive effect on technical efficiency and a negative effect on CO2 emissions. Therefore, future policy design and analyses should reflect the implications for regional elasticities of fossil fuel substitution and associated environmental outcomes. [ABSTRACT FROM AUTHOR]

We compare sustainably managed with unmanaged forests in terms of their contribution to climate change mitigation based on published data. For sustainably managed forests, accounting of carbon (C) storage based on ecosystem biomass and products as required by the United Nations Framework Convention on Climate Change is not sufficient to quantify their contribution to climate change mitigation. The ultimate value of biomass is its use for biomaterials and bioenergy. Taking Germany as an example, we show that the average removals of wood from managed forests are higher than stated by official reports, ranging between 56 and 86 mill. m3 year−1 due to the unrecorded harvest of firewood. We find that removals from one hectare can substitute 0.87 m3 ha−1 year−1 of diesel, or 7.4 MWh ha−1 year−1, taking into account the unrecorded firewood, the use of fuel for harvesting and processing, and the efficiency of energy conversion. Energy substitution ranges between 1.9 and 2.2 t CO2 equiv. ha−1 year−1 depending on the type of fossil fuel production. Including bioenergy and carbon storage, the total mitigation effect of managed forest ranges between 3.2 and 3.5 t CO2 equiv. ha−1 year−1. This is more than previously reported because of the full accounting of bioenergy. Unmanaged nature conservation forests contribute via C storage only about 0.37 t CO2 equiv. ha−1 year−1 to climate change mitigation. There is no fossil fuel substitution. Therefore, taking forests out of management reduces climate change mitigation benefits substantially. There should be a mitigation cost for taking forest out of management in Central Europe. Since the energy sector is rewarded for the climate benefits of bioenergy, and not the forest sector, we propose that a CO2 tax is used to award the contribution of forest management to fossil fuel substitution and climate change mitigation. This would stimulate the production of wood for products and energy substitution. [ABSTRACT FROM AUTHOR]

Promoting Plug-In Hybrid Vehicles (PHEVs) is viewed as a promising strategy to mitigate the energy consumption and greenhouse gas (GHG) emissions in the transportation sector. The actual fuel and electricity energy consumption of PHEVs has recently attracted increasing attention. Distance-based average electricity or fuel consumption is commonly adopted to evaluate the energy efficiency of a vehicle. However, previous studies have predominantly focused on the ratio of electric drive distance to fuel drive distance and did not consider the difference between the electricity generated from onboard engine and offboard grid charging. This study proposes a grid electric driving ratio (grid-EDR) based on the battery energy variation under real road operation conditions for a more accurate calculation of the PHEV electric distance ratio. The method is validated by the actual vehicle driving data of 49 PHEVs in Shanghai and compared with other methods. To evaluate its application, the fuel substitution was calculated using grid-EDR combined with the new European driving cycle fuel consumption calculation method. PHEVs with higher grid-EDRs demonstrate better fuel economy. More than half the PHEVs in this study saved 50–80% of their onboard fuel. By improving the charging frequency, such as constructing more charging infrastructure, grid-EDR can be increased to 0.88 to reduce fuel consumption and greenhouse gas emissions from the transportation sector. [ABSTRACT FROM AUTHOR]

Highly efficient and stable supported non-noble metal catalysts to realize the real-time evolution of hydrogen for the promising substitution of fossil fuels are urgently desired but are still greatly challenging to achieve. In this work, a highly dispersed ultrafine CoNi nanoalloy has been successfully enclosed within a hierarchically porous carbon which exhibits a unique core–shell metal@carbon structure through an in situ carbonized reduction approach by using bimetallic CoNi-MOF-74 as a self-sacrificed template. Note that the all-around interactions between the nanoalloy and carbon within such a unique hierarchically porous core–shell can effectively stabilize and activate the CoNi nanoalloy, meanwhile facilitating the fast mass transfer of substrate molecules. We found that the Co/Ni ratio of the original precursors of MOF-74 and the pyrolysis temperature can significantly meditate the catalytic performance of the derived composite catalysts. In particular, the synthesized catalyst, 10%-CoNi/HPC-400, showed the best catalytic activity and good stability for hydrogen evolution with a turnover frequency value (TOF) of 27.22 min−1 at 323 K, which is higher than most reported non-noble metal catalysts and even some noble metal catalysts. The outstanding catalytic performance and durability of the composite catalysts were attributed to the synergic effect of the well-dispersed CoNi alloy and the unique hierarchical core–shell structure, which demonstrated the huge potential for AB hydrolysis in hydrogen storage applications. [ABSTRACT FROM AUTHOR]

Background: Many governments take the view that voluntary national targets to reduce greenhouse gas emissions are sufficient to avoid negative climate effects. In the absence of independent verification, however, pledges are unlikely to be sufficient for a rapid and strong reduction of emissions. It is often claimed that a global carbon tax could be an effective instrument. However, such a tax is difficult to set and to collect, especially in countries with poor administrative infrastructure. Results: Here, we formulate and discuss a novel approach, the Global Carbon Surcharge (GCS), that mimics a carbon tax but does not require tax collection by governments. We define GCS as a requirement or a voluntary commitment encompassing all companies extracting carbon-carrying raw materials, namely coal, oil, gas and limestone, with the aim to burden their extraction with costs proportional to their carbon intensity. GCS mandates all companies to store these materials immediately after mining for a given period of time in the vicinity of the production site. Thereby, GCS generates additional costs that propagate through all sectors of the global economy. We elucidate how the investment costs for the storage infrastructure translate into surcharges on the raw materials. Conclusions: We show that by a proper choice of the storage time and the size of the storage unit, GCS becomes equivalent to a carbon tax in the range between 50 and 100 € per ton of CO2 that is assumed to be necessary for the transition to a carbon-neutral energy system. An attractive feature of GCS is that it can be verified, in particular by citizens themselves, using publicly available satellite data. Finally, if compulsory storage is coupled to blockchain-based smart contracts and a mandatory (expensive) mining of cryptocurrency, GCS can be operated without governmental protectionism, corruption and fraud. However, the main uncertainties of the GCS approach lie in the substantial expansion of infrastructure and the fact that the induced price effects must be sufficient to achieve a rapid and far-reaching substitution of fossil fuels. [ABSTRACT FROM AUTHOR]

Limiting fuel sulfur content (FSC) is a widely adopted approach for reducing ship emissions of sulfur dioxide (SO2) and particulate matter (PM), particularly in emission control areas (ECAs), but its impact on the emissions of volatile organic compounds (VOCs) is still not well understood. In this study, emissions from ships at berth in Guangzhou, southern China, were characterized before and after the implementation of the fuel switch policy (IFSP) with an FSC limit of 0.5 % in the Pearl River Delta ECA (ECA-PRD). After IFSP, the emission factors (EFs) of SO2 and PM 2.5 for the coastal vessels decreased by 78 % and 56 % on average, respectively; however, the EFs of the VOCs were 1807±1746 mg kg -1 , approximately 15 times that of 118±56.1 mg kg -1 before IFSP. This dramatic increase in the emissions of the VOCs might have been largely due to the replacement of high-sulfur residual fuel oil with low-sulfur diesel or heavy oils, which are typically richer in short-chain hydrocarbons. Moreover, reactive alkenes surpassed alkanes to become the dominant group among the VOCs, and low-carbon-number VOCs, such as ethylene, propene and isobutane, became the dominant species after IFSP. As a result of the largely elevated EFs of the reactive alkenes and aromatics after IFSP, the emitted VOCs per kilogram of fuel burned had nearly 29 times greater ozone formation potential (OFP) and approximately 2 times greater secondary organic aerosol formation potential (SOAFP) than those before IFSP. Unlike the coastal vessels, the river vessels in the region used diesel fuels consistently and were not affected by the fuel switch policy, but the EFs of their VOCs were 90 % greater than those of the coastal vessels after IFSP, with approximately 120 % greater fuel-based OFP and 70 %–140 % greater SOAFP. The results from this study suggest that while the fuel switch policy could effectively reduce SO2 and PM emissions, and thus help control PM 2.5 pollution, it will also lead to greater emissions of reactive VOCs, which may threaten ozone pollution control in harbor cities. This change for coastal or ocean-going vessels, in addition to the large amounts of reactive VOCs from the river vessels, raises regulatory concerns for ship emissions of reactive VOCs. [ABSTRACT FROM AUTHOR]

In the present work, dual fuel operation of a diesel engine has been experimentally investigated using biodiesel and hydrogen as the test fuels. Jatropha Curcas biodiesel is used as the pilot fuel, which is directly injected in the combustion chamber using conventional diesel injector. The main fuel (hydrogen) is injected in the intake manifold using a hydrogen injector and electronic control unit. In dual fuel mode, engine operations are studied at varying engine loads at the maximum pilot fuel substitution conditions. The engine performance parameters such as maximum pilot fuel substitution, brake thermal efficiency and brake specific energy consumption are investigated. On emission side, oxides of nitrogen, hydrocarbon, carbon monoxide and smoke emissions are analysed. Based on the results, it is found that biodiesel-hydrogen dual fuel engine could utilize up to 80.7% and 24.5% hydrogen (by energy share) at low and high loads respectively along with improved brake thermal efficiency. Furthermore, hydrocarbon, carbon monoxide and smoke emissions are significantly reduced compared to single fuel diesel engine operation. Exhaust gas recirculation (EGR) has also been studied with biodiesel-hydrogen dual fuel engine operations. It is found that EGR could improve the utilization of hydrogen in dual fuel engine, especially at the high loads. The effect of EGR is also found to reduce high nitrogen oxide emissions from the dual fuel engine and brake thermal efficiency is not significantly affected. • Biodiesel-H 2 dual fuel operation of the diesel engine has been experimentally studied. • Performance features with maximum pilot fuel substitution and emissions are analysed. • Biodiesel showed better pilot fuel substitution at low load and low emission. • It was possible to significantly reduce NO x emissions at high load using EGR. [ABSTRACT FROM AUTHOR]

This paper describes the reversible operation of a highly efficient microtubular solid oxide cell (SOC) with a nickelate-based oxygen electrode. The fuel cell was composed of a microtubular support of nickel and yttria stabilized zirconia (Ni-YSZ), an YSZ dense electrolyte, and a double oxygen electrode formed by a first composite layer of praseodymium nickelate (PNO) and gadolinium-doped ceria (CGO) and a second one of PNO. A good performance of the cell was obtained at temperatures up to 800 °C for both fuel cell (SOFC) and electrolysis (SOEC) operation modes, specially promising in electrolysis mode. The current density in SOEC mode at 800 °C is about −980 mA cm−2 at 1.2V with 50% steam. Current density versus voltage curves (j-V) present a linear behavior in the electrolysis mode, with a specific cell area resistance (ASR) of 0.32 Ω cm−2. Durability experiments were carried out switching the voltage from 0.7V to 1.2V. No apparent degradation was observed in fuel cell mode and SOEC mode up to a period of about 100 h. However, after this period especially in electrolysis mode there is an accumulated degradation associated to nickel coarsening, as confirmed by SEM and EIS experiments. Those results confirm that nickelate based oxygen electrodes are excellent candidates for reversible SOCs. • PNO-CGO composite electrode enhances the stability of SOC cells. • Highest electrolysis performance for a microtubular cell was achieved. • Switching to fuel cell mode partially recovers the degradation in electrolysis. [ABSTRACT FROM AUTHOR]

Recent developments have rendered the Dual Fuel (DF) engines an attractive alternative solution for achieving cost-efficient compliance to environmental regulations. The present study focuses on the safety investigation of a marine DF engine in order to identify potential safety implications. This investigation is based on an integrated engine model, which was developed in GT-ISE™ software and is capable of predicting both the engine steady-state behaviour and transient response. The model includes the engine thermodynamic simulation module as well as the engine control system functional module; the latter is responsible for implementing the ordered load changes and the operating mode switching. The developed model is first validated against available published data and subsequently used to simulate several test cases with fuel changes, from gas to diesel and diesel to gas with rapid and with delayed wastegate valve operation. The derived simulation results are used to investigate the potential safety implications that can arise during the engine operation. The results demonstrate that the engine–turbocharger matching as well as the wastegate control are critical parameters for ensuring the compressor surge free operation during gas to diesel modes transition. Abbreviations: 0D: zero-dimensional; 1D: one-dimensional; BMEP: brake mean effective pressure; CO2: carbon dioxide; DF: dual fuel; D/G: diesel generator; DTG: diesel to gas fuel modes switching; ECA: emission control area; ECS: engine control system; EEDI: energy efficiency design index; GTD: gas to diesel modes switching; HFO: heavy fuel oil; IMO: International Maritime Organization; LFO: light fuel oil; LNG: liquefied natural gas; MCR: maximum continuous rating; NOx: nitrogen oxides; PHA: preliminary hazard analysis; PI: proportional–integral; SOx: sulphur oxides; TC: turbocharger; WG: wastegate; λ: air–fuel equivalence ratio [ABSTRACT FROM AUTHOR]

Substitution of fossil gaseous fuels with biomass-based gases is of interest to the iron and steel industry due to its role in the mitigation of anthropogenic CO 2 emissions. In switching from fossil fuels to biomass-based gases, a systems analysis of the full value chain from biomass supply to the production and supply of final gas products becomes crucial. This study uses process and heat integration methods in combination with a supply chain evaluation to analyse full value chains of biomass-based gases for fossil gas replacement within the iron and steel industry. The study is carried out as a specific case study in order to understand the implications of utilizing bio-syngas/bio-SNG as heating fuels in iron- and steel-making, and to provide insights into the most sensitive parameters involved in fuel switching. The results show a significant cost difference in the fuel production of the two gas products owing to higher capital and biomass use in the bio-SNG value chain option. When tested for sensitivity, biomass price, transportation distance, and capital costs show the most impact on fuel production costs across all options studied. Trade-offs associated with process integration, plant localisation, feedstock availability and supply were found to varying extents. • Options to replace natural gas with biomass-based gases in iron and steel industry. • Integrated gas production at the steel plant has the lowest overall costs. • Supply of gas becomes cost-competitive with biomass supply at longer distances. • Trade-offs across key factors are observed to varying extents. [ABSTRACT FROM AUTHOR]

Due to increasing concern of the Indonesian government towards the ever increasing national level of carbon emissions and the increasing demand of oil, in 2014 the Indonesian National Energy Council released the National Energy Policy which set the target of an increased renewable energy portion to become 23% of the total national energy consumption while setting a limit to oil consumption to be at most 25%. As the road transportation sector consumes more than 60% of the national oil consumption, measures targeting this sector will be important in fulfilling the target. A model has been set up to evaluate the impact of the measures on oil consumption via two main avenues: the substitution of oil based fuels with alternative fuels (e.g. biofuel, compressed natural gas/CNG), the reduction of oil consumption via vehicle retirement and the acceleration of fuel economy improvement for vehicles. Results have shown that it is important that policies consider the presence of older vehicles in the population since there is presently no vehicle retirement policy or penalty for older vehicles resulting in a large number of old vehicles still being operational. Thus, introduction of new vehicles will have a limited effect on the average fuel efficiency. Implementation of a vehicle retirement policy to reduce the amount of older vehicles is shown to be very effective in stemming the increase of oil consumption. In regards to fuel substitution, oil substitution with ethanol is most impactful, as most motor vehicles in Indonesia rely on gasoline including the rapidly increasing motorcycle population. While oil consumption is also reduced by biodiesel substitution, impact is more limited due to a smaller diesel vehicle population with a lower annual increase of vehicle population. In addition, financial, social and regulatory barriers exist that impend implementation of alternative fuels and vehicle limitation schemes. We also evaluated possible barriers and avenues that can further promote these measures to meet the national energy policy target. • The impact of fuel substitution of Indonesian road transportation energy was simulated. • The avenues in order to meet the national energy policy target were evaluated. • Fuel substitution with ethanol is the most impactful for the Indonesian transportation energy sector. • Oil consumption can be also reduced by biodiesel substitution. • Regulatory barriers exist in the implementation of alternative fuels and vehicle limitation schemes. [ABSTRACT FROM AUTHOR]

Aim: An emerging framework for tropical ecosystems states that fire activity is either "fuel build‐up limited" or "fuel moisture limited", that is, as you move up along rainfall gradients, the major control on fire occurrence switches from being the amount of fuel, to the moisture content of the fuel. Here we used remotely sensed datasets to assess whether interannual variability of burned area is better explained by annual rainfall totals driving fuel build‐up, or by dry season rainfall driving fuel moisture. Location: Pantropical savannas and grasslands. Time period: 2002–2016. Methods: We explored the response of annual burned area to interannual variability in rainfall. We compared several linear models to understand how fuel moisture and fuel build‐up effect (accumulated rainfall during 6 and 24 months prior to the end of the burning season, respectively) determine the interannual variability of burned area and explore if tree cover, dry season duration and human activity modified these relationships. Results: Fuel and moisture controls on fire occurrence in tropical savannas varied across continents. Only 24% of South American savannas were fuel build‐up limited against 61% of Australian savannas and 47% of African savannas. On average, South America switched from fuel limited to moisture limited at 500 mm/year, Africa at 800 mm/year and Australia at 1,000 mm/year of mean annual rainfall. Main conclusions: In 42% of tropical savannas (accounting for 41% of current area burned) increased drought and higher temperatures will not increase fire, but there are savannas, particularly in South America, that are likely to become more flammable with increasing temperatures. These findings highlight that we cannot transfer knowledge of fire responses to global change across ecosystems/regions—local solutions to local fire management issues are required, and different tropical savanna regions may show contrasting responses to the same drivers of global change. [ABSTRACT FROM AUTHOR]

The ability to switch fuels for oxidation in response to changes in macronutrient composition of diet (metabolic flexibility) may be informative of individuals' susceptibility to weight gain. Seventy-nine healthy, weight-stable participants underwent 24-h assessments of energy expenditure and respiratory quotient (RQ) in a whole-room calorimeter during energy balance (EBL) (50% carbohydrate, 30% fat) and then during 24-h fasting and three 200% overfeeding diets in a crossover design. Metabolic flexibility was defined as the change in 24-h RQ from EBL during fasting and standard overfeeding (STOF) (50% carbohydrate, 30% fat), high-fat overfeeding (HFOF) (60% fat, 20% carbohydrate), and high-carbohydrate overfeeding (HCOF) (75% carbohydrate, 5% fat) diets. Free-living weight change was assessed after 6 and 12 months. Compared with EBL, RQ decreased on average by 9% during fasting and by 4% during HFOF but increased by 4% during STOF and by 8% during HCOF. A smaller decrease in RQ, reflecting a smaller increase in lipid oxidation rate, during HFOF but not during the other diets predicted greater weight gain at both 6 and 12 months. An impaired metabolic flexibility to acute HFOF can identify individuals prone to weight gain, indicating that an individual's capacity to oxidize dietary fat is a metabolic determinant of weight change. [ABSTRACT FROM AUTHOR]