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Abstract Railways are a rather efficient transport mean, and yet there is increasing interest in reducing their energy consumption and making them more sustainable in the current context of climate change. Many studies try to model, analyse and optimise the energy consumed by railways, and there is a wide diversity of methods, techniques and approaches regarding how to formulate and solve this problem. This paper aims to provide insight into this topic by reviewing up to 52 papers related to railways energy consumption. Two main areas are analysed: modelling techniques used to simulate train(s) movement and energy consumption, and optimisation methods used to achieve more efficient train circulations in railway networks. The most used methods in each case are briefly described and the main trends found are analysed. Furthermore, a statistical study has been carried out to recognise relationships between methods and optimisation variables. It was found that deterministic models based on the Davis equation are by far (85% of the papers reviewed) the most common in terms of modelling. As for optimisation, meta-heuristic methods are the preferred choice (57.8%), particularly Genetic Algorithms. Highlights • Modelling and optimisation methods for railways energy efficiency are reviewed. • Modelling methods provide reliable simulations of the trains' energy consumption. • Optimisation methods help obtaining the most efficient solutions for train traffic. • Most used modelling methods are deterministic, based on Davis equation. • Most used optimisation methods are meta-heuristics, mainly genetic algorithms. [ABSTRACT FROM AUTHOR]

Abstract Energy efficiency improvement is usually regarded as an effective way to decrease energy consumption and to fight climate change, but it also booms energy consumption through rebound effects. But the improvement of energy efficiency also has rebound effects, which increases energy consumption and emission. So this paper arms to capture the rebound effects of efficiency improvement by considering zero-cost breakthrough of energy efficiency and price jump of energy purchase. First, energy efficiency improvement, measured by zero-cost breakthrough of energy efficiency, stimulates energy consumption, but it may reduce the total emission. Second, both the direct and indirect rebound effects of energy efficiency improvement on energy consumption and environment are captured. Interestingly, jumping energy price decreases both the direct and indirect rebound effect. Finally, the result of the paper shows that restriction of individuals' entry or competition restriction moderates the rebound effects of energy efficiency improvement. Highlights • Effect of competition on energy efficiency rebound effects is developed in theory. • Rebound effects of energy efficiency are captured under zero-cost breakthrough. • Moderate monopoly is proofed to be helpful for reducing energy efficiency rebound effects. • Improvement of energy efficiency has both direct and indirect rebound effects. • Energy price jump has offset effects on rebound effects of efficiency promotion. [ABSTRACT FROM AUTHOR]

Policies targeting energy efficiency and renewable energy are sometimes viewed as more politically feasible than carbon pricing in pursuit of emission reduction goals. This paper assesses underlying drivers of energy policy development. These factors include economic, social, environmental, and institutional variables. The between estimator for panel data is an appropriate method for our focus on some exogenous variables that vary more across countries than over time. We find that larger oil reserves per capita have a negative relationship with renewable energy policy development. Education and political globalisation have strong positive relationships with both energy-efficiency and renewable-energy policy development. These results suggest that greater participation in global political groups can be an indirect approach toward energy policy development, in cases where direct and immediate policies are hard to implement. OECD countries have higher policy scores by 33 and 25 points in energy efficiency and renewable energy respectively. Blinder-Oaxaca decomposition analysis shows that these higher scores are primarily due to social and political institution predictors rather than economics and physical endowments. • Large-n cross country international sample on continuous policy score measurement. • Political globalisation is positively linked with renewables and energy efficiency policies. • Education is positively linked to energy policy development, especially for efficiency. • Higher OECD countries' policy scores are primarily due to social and political predictors. • Higher incomes are unlikely to lead to automatic improvements in energy policies. [ABSTRACT FROM AUTHOR]

The building sector is considered as the biggest single contributor to world energy consumption and greenhouse gas emissions. Therefore, a good understanding of the nature and structure of energy use in buildings is crucial for establishing the adequate future energy and climate change policies. Availability of the updated data is becoming increasingly important in order to allow a rigorous analysis. In this paper, recent data on the world energy consumption in both residential and commercial buildings are reported. Past situation, current status and future trends are discussed and analyzed for selected countries. A breakdown of buildings energy consumption is realized in order to determine the influencing key parameters. A whole section of this paper is dedicated to give an overview of measures and policies adopted by different countries, allowing the monitoring, management and reduction of the energy consumption in buildings. Critical aspects of these policies are discussed based on the feedback of the early adopters. [ABSTRACT FROM AUTHOR]

Over the recent decades, there has been an increasing focus on energy-efficient operation of vessels. It has become part of the political agenda, where regulation is the main driver, but the maritime industry itself has also been driven towards more energy-efficient operation of the vessels, due to increasing fuel costs. Improving the energy efficiency on board vessels is not only a technical issue - factors such as awareness of the problem, knowledge skills and motivation are also important parameters that must be considered. The paper shows how training in energy-efficient operation and awareness can affect the energy consumption of vessels. The study is based on navigational, full-mission simulator tests conducted at the International Maritime Academy SIMAC. A full-mission simulator is an image of the world allowing the students to obtain skills through learning-by-doing in a safe environment. Human factors and technical issues were included and the test sessions consisted of a combination of practical simulator exercises and reflection workshops. The result of the simulator tests showed that a combination of installing technical equipment and raising awareness - making room for reflections-on and in-action - has a positive effect on energy consumption. The participants, on average, saved approximately 10% in fuel. [ABSTRACT FROM AUTHOR]

The mitigation of climate change is the main issue for environmental policymakers. A large number of authors analysed the impact of various factors on greenhouse gas (GHG) emissions. In this paper, we proposed a multiplicative approach to use 2- and 3-way interactions simultaneously in order to analyse the effects of energy efficiency, renewable energy and sector mix as the moderators that shape the economic activity – environmental degradation nexus. The results encompassing global panel data show that the turning point increased from 1990 to 1995 to 2002–2007 and decreased afterwards. Considering the analysis of moderators, a high share of agriculture and industry sectors make the curve flat with a positive slope and a high level of economic activity was associated with more GHG emissions with no turning point. The marginal effect of energy efficiency to reduce the negative impact of agriculture and industry sectors was growing. Meanwhile, the marginal effect of renewables to reduce the negative impact of agriculture and industry sectors was diminishing. Service sector and energy efficiency, service sector and renewables worked as the substituting forces reducing GHG emissions with a diminishing marginal rate of substitution. Therefore, this study confirms that the economic activity – environmental degradation relationship is very complex and further studies should consider the role of the moderators of this nexus. [Display omitted] • Technique, composition effects should be considered as moderators of HGH emissions. • The multiplicative approach was applied to model interactions of GHG factors. • Agriculture, industry sectors made the economic activity GHG emissions curve flat. • Marginal effect of renewables to reduce GHG emissions was diminishing. • Service sector and renewables worked as substituting forces reducing emissions. [ABSTRACT FROM AUTHOR]