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Carbon dioxide valorization into value added products have become subject to much study to reduce industrial CO 2 emissions and fossil energy resource consumption. In this context, the purpose of this study is to evaluate and highlight the interest of CO 2 conversion into methanol through a complete techno-economic and environmental assessment of the entire process chain. The integrated process, successfully implemented in Aspen Plus®, is designed to treat the CO 2 coming from a conventional cement plant. A MEA-based CO 2 capture process is considered, and the captured CO 2 is then directly sent to the conversion unit for its catalytic conversion. Consequently, combining the two units leads to relevant integrations, especially regarding the reuse of the heat provided by the exothermal methanol reactions for the regeneration of the CO 2 capture solvent. An economic assessment is proposed to estimate the operational and investment costs, as well as the net present value, which demonstrates that the economic feasibility strongly depends on electricity and H 2 production costs. A Life Cycle Analysis method is finally performed to identify the main environmental hotspots. The underlying process design offers a significant reduction in greenhouse gases (besides other categories) when compared to the conventional fossil production from natural gas. • An integrated process is studied to produce methanol from industrial CO 2. • Techno-economic and environmental aspects are assessed. • Economics of CO 2 -to-methanol is affected by high renewable H 2 production costs. • Environmental benefits are highlighted compared to conventional production. • CO 2 -to-methanol is a credible substitution alternative in climate change mitigation. [ABSTRACT FROM AUTHOR]

Large gas engines will play a significant role in distributed power generation for the energy supply of the future. The lower amount of carbon in natural gas in comparison with other fossil fuels can be used to bridge the gap between a carbon‐based and a carbon‐free energy supply. The main objective of this paper is to provide an overview of the technological challenges the next generation of gas engines will face. Improvements in robustness and dynamic behavior will allow gas engines to meet the high transient requirements for the future power supply. The great fluctuations in gas quality anticipated with grid gas and liquefied natural gas impose high demands on both the transient behavior and the knock resistance of the engine. Technologies that enhance fuel flexibility by enabling sustainable power and heat generation using hydrogen‐rich syngas from biomass and the efficient use of waste gases will be key. The most important technological components that maximize power output and efficiency as well as transient operation at very low emission levels are discussed. An advanced development methodology is applied in order to deal with the requirements presented by the technological challenges. The main future goals of gas engine development will be described by use of examples to illustrate the application of the methodology. In summary, the research and technological developments presented in this paper will support the transition from conventional to carbon‐free fuel for reliable and sustainable power generation that meets future requirements for large gas engines. [ABSTRACT FROM AUTHOR]

To illustrate the power and utility of macro-level decomposition tools, this article presents a structured comparison of two all-sector global modeling exercises that assess emissions reductions compatible with climate stabilization at roughly 1.5C above pre-industrial levels. It uses an expanded Kaya Identity combined with the LMDI (Logarithmic Mean Divisia Index) method to decompose the effects of key drivers of changes in emissions over time in these scenarios. The most important drivers of emissions reductions include final energy intensity of economic activity, the fraction of primary energy delivered by fossil fuels, and emissions from non-CO 2 warming agents. Land-use change and the carbon intensity of fossil energy are also important. The article suggests additional data modelers should release to allow more rapid analysis of results and ways to facilitate cross-study comparisons (such as adopting "best of breed" sectoral models instead of relying solely on in-house expertise for model development). Global change; Climate change; Emissions reduction modeling; Model comparisons; Energy resources; Environmental policy; Environmental technology; Energy Policy. • Detailed decomposition analysis gives visibility into key drivers and model structure. • Key drivers include energy intensity, fossil fuel fraction, and non-CO 2 warming agents. • Analyzing "edge cases" can help suggest superior technology/policy combinations. • Analyzing "edge cases" can help demonstrate the limits of feasible climate mitigation. • "Best of breed" sectoral models are an essential complement to IAMs. [ABSTRACT FROM AUTHOR]

The impact of global warming and an increase in the indoor cooling equipments using energy sources other than conventional energy have become very attractive because they can reduce consumption of fossil fuels as well as harmful emissions in to the environment. The solar energy is one of the readily available forms of renewable energy which can be used to operate the cooling equipments depending on the geographical location of the area where solar cooling system needs to be installed. The effectiveness of solar cooling also needs to be evaluated based on various performance indicating parameters. However, different types of solar collectors also need to be evaluated in order to find out their feasibility for cooling applications. Thus in this article review of different types of solar cooling technologies have been carried out. The study reveals that evacuated tube collectors are best option for solar cooling where as desiccant cooling helps in improving the indoor air quality. Also, thermal energy storage and ejector based solar cooling efficiently improves the performance besides energy saving. [ABSTRACT FROM AUTHOR]

Waste, Energy and Transport are three of the main sectors of the human society. The three sectors have substantially been studied in their individual right and there is a plethora of literature available on them individually and also collectively in varying combinations. For instance, Waste to Energy is a well-established field, and so is the energy usage by the transport sector. However, there is an extreme knowledge gap in connection to energy being generated by incinerating waste in order to propel the means of the transport be it in air/aviation, terrestrial/automobile and locomotives or water/marine vessels. The paper focuses on this knowledge gap, thereby, aiming to create theoretical models of this concept. Therefore, the core nature of this study is conceptual. Relevant secondary data is drawn from the existing literature in the form of numbers and graphs to quantitatively establish the state of each of the three sectors before being joined together into a new nexus called Waste to Energy for Transport and abbreviated as WET Nexus. An account of challenges as well as benefits is outlined regarding the possibility of replacing the consumption of fossil fuel by waste-to-energy i.e. a kind of 'on-board' waste incineration to propel maritime vessels and also supply energy to 'on-board' built environments. Thus, killing two birds (transport and waste) with one stone (energy). The paper also touches upon innovative insights and future research potentials in terms of how maritime transport being driven by energy-from-waste instead of fossil fuels, can improve environmental sustainability; help climate emergency agendas and; also contribute to the Climate Action, which is one of the seventeen SDGs (Sustainable Development Goals) introduced by the UN (United Nations). [Display omitted] • The exponential rise in global population has correspondingly been increasing the waste generation and energy demand, while the transport sector alone is the second largest energy consumer. • The paper introduces an innovative idea in which the three sectors – Waste (W), Energy (E) and Transport (T) – are conceptually amalgamated and abbreviated as WET Nexus. • The nexus – Waste to Energy for (propelling the) Transport – has potential to contribute to decarbonise the transport sector while reducing waste to landfills and reducing reliance on fossil-fuel energy. • The connection of the innovative nexus with the atmosphere /air, hydrosphere /water, and lithosphere /soil or land, is delineated. • Climate change and sustainability are the cross-cutting themes and the SDGs (Sustainable Development Goals) by the United Nations are also briefly, theoretically interwoven with the WET Nexus. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an assessment of global economic energy potentials for all major natural energy resources. This work is based on both an extensive literature review and calculations using natural resource assessment data. Economic potentials are presented in the form of cost-supply curves, in terms of energy flows for renewable energy sources, or fixed amounts for fossil and nuclear resources, with strong emphasis on uncertainty, using a consistent methodology that allow direct comparisons to be made. In order to interpolate through available resource assessment data and associated uncertainty, a theoretical framework and a computational methodology are given based on statistical properties of different types of resources, justified empirically by the data, and used throughout. This work aims to provide a global database for natural energy resources ready to integrate into models of energy systems, enabling to introduce at the same time uncertainty over natural resource assessments. The supplementary material provides theoretical details and tables of data and parameters that enable this extensive database to be adapted to a variety of energy systems modelling frameworks. [Copyright &y& Elsevier]

• A multi-GCM ensemble simulation and optimization approach is developed. • The developed approach can effectively tackle multiple uncertainties. • The impact of climate change on energy-economy-carbon nexus system is investigated. • Renewable energy will gradually replace fossil fuel for mitigating climate change. • There is a tradeoff between carbon dioxide emission and system cost. Climate change mitigation by reducing carbon dioxide emission becomes one of the major challenges for energy systems. In this study, a multi-GCM ensemble simulation and optimization approach is developed for analyzing the impact of climate change on China's energy-economy-carbon nexus system under multiple uncertainties through integrating techniques of multiple global climate models, support-vector-regression, Monte Carlo simulation, and interval chance-constrained programming within a general framework. The developed approach can tackle multiple uncertainties existed in global climate models, random carbon dioxide emission and complex optimization process. Results disclose that (i) the national electricity demand would grow around 58.6% in the next 30 years under climate change; (ii) for climate change mitigation and sustainable development, fossil fuel would be gradually replaced by renewable energy (i.e. the share of fossil fuel to the total energy supply decreasing 22.5% and the share of electricity generated from renewable energy increasing 27.0% by 2050); (iii) compared to the peak value in 2030, carbon dioxide emission would reduce 15.1% by 2050, most reduction from coal-fired power generation; (iv) there is a tradeoff between carbon dioxide emission and system cost as p-level decreases from 0.15 to 0.01 (i.e. carbon dioxide emission can reduce 1.9% with 3.7% of raised system cost). It is desired for China to adjust its current energy supply structure for reducing carbon emission and seeking a low-carbon developmental path. The most effective way is to eliminate some small coal-fired units. A number of wind-power and solar-power projects are expected to be implemented due to their abundant potential markets. [ABSTRACT FROM AUTHOR]