Analysis of the recent evolution of commercial air traffic CO2 emissions and fleet utilization in the six largest national markets of the European Union

This paper presents the results of a study performed to analyze the evolution of commercial air traffic and CO₂ emissions in the European Union, from 2010 to 2013. Data sources are the European Commission's Eurostat Air Transport Statistics (Eurostat) and EUROCONTROL flight plans database. The changes in the fuel efficiency are analyzed and the potential reasons for those changes investigated. The evolution in the airline fleet composition during the last decade is presented as one of the reasons for the improvement in fuel efficiency, measured in burnt fuel per total Revenue Tonne Kilometre (RTK), as well as the different parameters depending on the airline business model (network carriers, low cost companies, etc.) and the aircraft type.Results show a slight reduction in the traffic, both for passengers and cargo (about −0.8%), and a more important reduction in CO₂ emissions (−4.3%), thanks to an improvement in the fuel efficiency parameter (−3.5%) for the three years period. There has been a relevant change in the fleet composition in the last ten years, with the replacement of older models for more efficient ones, and a shift to larger aircraft, particularly in the regional segment. Traffic has decreased in shorter distances (internal EU traffic), but increased in more efficient long range flights (extra-EU traffic), resulting also in an improvement of the efficiency parameter as average aircraft size and stage length increases.     

The atmospheric carbon resilience problem: A theoretical analysis

We study a dynamic carbon pollution model where carbon accumulates both inside a nonrenewable and a renewable reservoir with a constant regeneration rate. Two primary energy sources are available: a cheap exhaustible fossil fuel (coal) and an expensive clean energy alternative (solar). To avoid catastrophic climate events, the global carbon concentration has to remain below some critical mandated ceiling. We show that there exists an upper bound on the coal endowment that can be consumed, which distinguishes two main cases: coal is initially abundant or scarce. If the energy sector has to provide a constant aggregate energy flow to the final users, cost-effectiveness requires that the global ceiling should be attained only when solar energy is introduced. Then the economy stays forever at the ceiling and coal use is progressively replaced by solar energy use. In the abundant coal case, this energy sources substitution process lasts for an infinite duration while in the scarce coal case, coal exploitation ends in finite time. Under a welfare maximization criterion, if coal is abundant, we show that the economy may follow a sequence of phases at the ceiling and below the ceiling before the final transition towards clean energy.     

Fuel hedging and airline operating costs

Fuel hedging is a common risk management tool used in the airline industry. But past studies have not addressed the question of whether fuel hedging creates any benefit to airline operations. This study is the first work that empirically examines the role of fuel hedging in reducing airlines’ operating costs. Using US airlines data from 2000 through 2012, we find that, after accounting for the presence of cost inefficiency, fuel-hedging airlines had about 9–12% lower operating costs, but this effect is statistically insignificant. Irrespective of the hedging status, US airlines could reduce operating costs by an average of 12–14% per year without reducing output.     

Climate change and the transition to a low carbon economy – Carbon targets and the carbon budget

Carbon intensive fuels generate a significant negative externality which is quite relevant for climate change mitigation policy. We propose a dynamic growth model where output is produced using two types of energy sources: fossil fuel and renewable energy. Fossil fuel discovery, extraction, and associated costs are incorporated in our model together with the dynamics of greenhouse gas emissions and consequent damages. Consistent with the empirical facts, our numerical solutions suggest that fossil fuels, especially coal, should not be exploited to depletion. Furthermore, renewable energy should be gradually phased in to meet targets consistent with the Paris 2015 agreement. We show that adopting those policies should slow down the growth rate of cumulative emissions; but the outcome is contingent upon the carbon emission targets set for advanced countries, as distinct from those assigned to developing countries.     

Evaluating new CO2 reduction technologies in Japan up to 2030

A mathematical model was developed for evaluating CO₂-reduction technologies in power generation, residential, commercial and road transport sectors in Japan. The existing and new power generation technologies evaluated included 34 centralized and 8 dispersed power generation technologies in the residential and commercial energy demand sectors. To take into account the varieties of useful energy and of its demand duration patterns among entities in the demand sectors, the hourly mean power and heating and cooling demand–supply balances in one residential and four commercial representative entities were considered for each month. The road transport sector addressed five types of automotive use. The useful-energy demands are exogenously given; the model calculates the technology installations that satisfy the demands to minimize the total systems cost for each year up to 2030. The availability of the new technologies, i.e., the first years they are installable, is derived from research and development (R&D) process analyses on the basis of surveys to experts. As a result of the model calculation, dispersed molten carbonate and solid oxide fuel cells and onboard gasoline reforming-type fuel cell vehicle (FCV) technologies are expected to have the largest economic values, approximately 60–120 billion constant 1998 yen [460–920 million U.S. dollars (USD)] among the evaluated new CO₂-reduction technologies. One of the implications from our calculations is that extending electric power corporations' commercial coverage to dispersed power generation, in addition to centralized power generation, is desirable to help lower overall costs in society, as well as to secure industry profits.     

燃料视角下青海可持续发展分析

青海省的牧区和农村普遍存在以牛粪作为燃料的现象。牛粪燃料虽然给人们的生活带来了方便，但是影响社会的可持续发展。因此，应充分利用当地日照充足的优势，发展“阳光能源”作为牛粪燃料的替代品。为了使燃料置换的可能性变为现实，还需要构建一套包括政府宏观调控、产业结构调整、生态意识培养、社会保障在内的机制。     

基于熵权的乏燃料公路运输选线模型

由于核电站的特殊性，乏燃料的运输在核电供应体系中占据重要地位。核电站乏燃料具有辐射性，运输过程中对工作人员、沿途公众和环境等可能会产生危害，又属于公路超限货包运输，所以对公路运输线路要求非常高。本文在利用层次分析法构造乏燃料公路运输线路优选系统的综合评价指标体系的基础上，结合熵权和模糊数学理论，构造基于熵权的乏燃料公路运输选线模糊层次分析模型，为确保核电供应链中乏燃料物流的安全、降低其对环境的影响提供决策依据，以达到安全、可靠和经济合理地完成核电站乏燃料运输的目的。     

Carbon dioxide emissions and inland container transport in Taiwan

The aim of this study is to estimate the carbon dioxide (CO₂) emissions from inland container transport during the time period of 1998-2008 and predicts the trend of these emissions. The analyses show that the CO₂ emission from inland container transport in 1992 reached 1.03 million tonnes, and the figure drastically increased by 89.3% to 1.95 million tonnes in 2008. Using a multiple regression model, gross domestic product (GDP) and oil price are found to be the key drivers for CO₂ emission. The CO₂ mitigation strategies are discussed in the policy suggestions given that Taiwan is warming at twice global average rate.     

日本核电力资源开发的特点及问题

电力资源供应是否充沛已成为目前制约世界经济稳定增长的主要因素,由于核发电优势明显,利用核动力开发电力资源业已成为一些国家保障经济发展的重要选择。日本是利用核能开发电力资源的大国,长期以来在"国策民营"体制下建立起来的核发电业有效地保障了经济的发展。但另一方面,日本在核发电业的发展过程中也表现出一些问题,这些问题对于意欲大规模发展核能的国家来说不仅具有参考价值,而且在国际合作开发与利用核电非常盛行的今天也具有十分重要的现实意义。