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The depletion of fossil fuel and the ozone layer has been a global concern for decades. The International Organization for Standardization has published earth-moving machine sustainability standards for the industry to provide information to satisfy their customers' interests in their construction projects. Furthermore, steeply rising energy prices and the collapse of financial institutions in recent years have sparked demand for ways to improve individual energy efficiency. Original equipment manufacturers of earth-moving machines must address sustainability requirements, as well as remaining competitive and they aim to do this by improving machine efficiency, adopting advanced fleet management systems, providing operator training courses etc. Clearly high fuel efficiency is important to reduce depletion of fossil fuels and damage to the environment. However, the objectives of achieving the highest possible productivity (m3/h) and improving fuel efficiency (kg/l) are often considered separately. Many equations have been formulated to measure a machine's highest possible productivity level, yet there is a lack of consensus between academia and industry sources on the terms which should be considered within such equations. Perhaps more importantly, none have explicitly considered the relationship between fuel efficiency and productivity, and only scant consideration is given to the role of operators in achieving optimum productivity for fuel efficiency. Therefore, this paper presents an eco-approach to enable operators to achieve optimal productivity for fuel efficiency of a hydraulic excavator. Hydraulic excavators are primarily designed for excavating with a bucket. Their ease of use, versatility and high productivity have won them major segments of the construction equipment market, therefore the focus on hydraulic exactors in this paper is justifiable. The research presented in this paper has adopted an applied research methodology to collect measurable, empirical evidence through scientific experiments in order to test several hypotheses that focus on the reduction of GHG produced by construction machines. The research has examined two variables, engine speed and bucket cut depth, to determine their effects on productivity and fuel efficiency of a hydraulic excavator. The experimental results show that the combinations of various engine speed settings and bucket cut depths can increase productivity by 30% and cut greenhouse gas emissions by 24%, consequentially moving 62% more spoil every hour for every litre of fuel consumed. The results also suggest that identifying the correct bucket cut depth is the key to significant improvements in productivity and reduction in greenhouse gas emissions. The paper therefore concludes that adoption of an appropriate construction machine operation style can help reduce the greenhouse gas emissions associated with hydraulic excavators. Hence, educating operators to select the right engine speed and bucket cut depth is a cost effective approach to lowering the operational costs and carbon emissions through lower fuel consumption and greater machine longevity.

Composite materials made of glass and carbon fibres have revolutionised many industries. Demand for\ud composites is experiencing rapid growth and global demand is expected to double. As demand for\ud composites grows it is clear that waste management will become an important issue for businesses.\ud Technically composite materials evoke difficult recycling challenges due to the heterogeneity of their\ud composition. As current waste management practices in composites are dominated by landfilling, governments\ud and businesses themselves foresee that this will need to change in the future. The recycling of\ud composites will play a vital role in the future especially for the aerospace, automotive, construction and\ud marine sectors. These industries will require different recycling options for their products based on\ud compliance with current legislation, the business model as well as cost effectiveness. In order to be able\ud to evaluate waste management strategies for composites, a review of recycling technologies has been\ud conducted based on technology readiness levels and waste management hierarchy. This paper analyses\ud 56 research projects to identify growing trends in composite recycling technologies with pyrolysis,\ud solvolysis and mechanical grinding as the most prominent technologies. These recycling technologies\ud attained high scores on the waste management hierarchy (either recycling or reuse applications) suggesting\ud potential development as future viable alternatives to composite landfilling. The research\ud concluded that recycling as a waste management strategy is most popular exploration area. It was found\ud mechanical grinding to be most mature for glass fibre applications while pyrolysis has been most mature\ud in the context of carbon fibre. The paper also highlights the need to understand the use of reclaimed\ud material as important assessment element of recycling efforts. This paper contributes to the widening\ud and systematising knowledge on maturity and understanding composites recycling technologies.

In a future fossil-free circular economy, the petroleum-based plastics industry must be converted to non-fossil feedstock. A known alternative is bio-based plastics, but a relatively unexplored option is deriving the key plastic building blocks, hydrogen and carbon, from electricity through electrolytic processes combined with carbon capture and utilization technology. In this paper the future demand for electricity and carbon dioxide is calculated under the assumption that all plastic production is electricity-based in the EU by 2050. The two most important input chemicals are ethylene and propylene and the key finding of this paper is that the electricity demand to produce these are estimated to 20 MWh/ton ethylene and 38 MWh/ton propylene, and that they both could require about 3 tons of carbon dioxide/ton product. With constant production levels, this implies an annual demand of about 800 TWh of electricity and 90 Mton of carbon dioxide by 2050 in the EU. If scaled to the total production of plastics, including all input hydrocarbons in the EU, the annual demand is estimated to 1600 TWh of electricity and 180 Mton of carbon dioxide. This suggests that a complete shift to electricity-based plastics is possible from a resource and technology point of view, but production costs may be 2 to 3 times higher than today. However, the long time frame of this paper creates uncertainties regarding the results and how technical, economic and social development may influence them. The conclusion of this paper is that electricity-based plastics, integrated with bio-based production, can be an important option in 2050 since biomass resources are scarce, but electricity from renewable sources is abundant.

The mining industry needs community and regional governmental support to maintain its current activities and, more importantly, to develop future projects. The failure to manage environmental risks in an acceptable manner during mine operation, closing and post-closing periods is a critical factor. The mining industry must regain its reputation that has been lost over decades and centuries of environmental degradation. Several environmental management tools (e.g., life cycle assessment, multi-criteria decision analysis, etc.) are widely applied during mine development, operation and closure periods. Nevertheless, due to uncertainties associated with the post-closure phase and the end of economic activity (implying no more revenues for stakeholders in the form of workers’ salaries and municipality taxes), it is crucial to adopt sound management practices during this period to achieve sustainability in the mining sector. As operational methodologies that can be used as a reference are lacking, the management of environmental risks during and after underground coal mine closures is, in many cases, limited or is developed without specific guidance. This statement is supported by the fact that the European Commission, through the Research Fund for Coal and Steel, encouraged research, pilot and demonstration projects and accompanying measures within the coal sector via the coal programme priority of recent years (2012–2014), namely, the “Management of environmental risks during or after mine closure”. The aim of this paper is to provide mine operators with an organized informational framework that could be applied during future underground coal mine closures independent of the major environmental problems faced and directly connected to the types and characteristics of coal and the exploitation methods used. The investigation was conducted using a literature review and interviews with experts from European universities, research institutions and coal mining companies from Poland and Spain.

Consumption of ready-made meals is growing rapidly and yet little is known about their economic and environmental impacts. This paper focuses on the economic aspects to estimate the life cycle costs, value added and consumer costs of ready-made meals, in comparison with the equivalent meals prepared at home. Their life cycle environmental impacts are also considered. A typical roast dinner is considered, consisting of chicken, vegetables and tomato sauce. Different production and consumption choices are evaluated, including sourcing of ingredients, chilled or frozen supply chains and types of appliance used by the consumer to prepare the meal. The estimated life cycle costs of the ready-made meal range from £0.61–£0.92 per meal and for the home-made from £0.68–£1.12. The lowest life cycle costs are found for the chilled ready-made meal heated in a microwave, 11% below the costs of the best home-made option. The life cycle costs of the frozen meal are similar to the best home-made option. The chilled ready-made meal has the highest value added (£2.01) compared to the frozen (£1.22) and the home-made meal (£0.44). However, from the consumer perspective, the cheapest option is the home-made meal (£1.17) while the chilled ready-made option is most expensive (£2.61). If the meal options are compared on both the life cycle costs and environmental impacts, the home-made meal is the best option overall. These findings can be used to inform both producers and consumers on how their choices influence costs and environmental impacts of food. The authors are grateful to BECAS Chile and UK Engineering and Physical Sciences Research Council, EPSRC (grant no. EP/K011820) for funding this research.

This review concerns the methodological challenges that industrial ecology faces in integrating natural and social sciences. Network analysis can be seen as the most promising method to mediate between industrial ecology's overall systems approach and the complex structures found in society. It is a well established method across scientific disciplines, including the social sciences. It has been successfully applied in industrial ecology, in which localized phenomena of industrial symbiosis have been a key focus, and where metrics from both the social and natural sciences are used to understand socio-metabolic structures. In this paper we classify such studies as Social-Material Network Analyses and we discuss the body of work, drawing on network analyses from various disciplines. A challenge is the hierarchical nature of industrial networks and how it can be addressed socially. We discuss the opportunities and limitations of metric-driven network analysis and offer a review of methodological options for Social-Material Network Analyses. © 2014 The Authors.