• Energy Research

Abstract The automotive industry is facing on-going challenges to improve the sustainability of its manufacturing processes and vehicle emissions due to economic, environmental, marketability and policy concerns. This review aims to evaluate steps that could be taken by automotive manufacturers to further reduce energy consumed during manufacturing processes, particularly focusing on thermal management of low-temperature heat sources that are extensively present in the whole plant and in the paint shop. Through an extensive literature review on the subject, this article presents vehicle production processes, the past and future drivers, and strategies towards sustainability. Firstly, the whole vehicle manufacturing process is explained focusing on the energy sources and their use in the plant. Then, the paint shop is described as being responsible for the highest energy consumption in the production process, focusing on components, paints and energy utilisation. After presenting the practice performed by automotive manufacturers to reduce the energy consumption of their production process in terms of energy efficiency and thermal management, the article is closed by future steps that could be undertaken by the automotive industry towards the realisation of a low-carbon sector. It is concluded that unexploited potential for heat recovery in the paint shop is present in the low-temperature range and this waste heat could be effectively exploited by liquid desiccant technology for energy consumption reduction and could increase paint quality of the painting process due to more efficient moisture control.

Polyethylene furandicarboxylate (PEF) is considered as a renewable-based solution to its fossil-based counterpart polyethylene terephthalate (PET). However, due to its lengthy and energy-intensive production process, PEF has not been established at a commercial scale. Here we present a new study on PEF produced from industrial carbon dioxide (CO2) emissions and non-food-derived biomass to provide an alternative for PET. We assess PEF production from an energy consumption, environmental impacts and production cost point of view at an industrial scale using mass and energy balance, life-cycle assessment and payback period. The results show that emissions and energy consumption can be reduced up to 40.5% compared with PET. Abiotic depletion (fossil) (6.90 × 104 MJ), global-warming potential (3.75 × 103 kg CO2-equivalent) and human toxicity potential (2.18 × 103 kg 1,4-dichlorobenzene equivalent) are the three most substantial impacts in producing one tonne of PEF. By applying optimal design and mature technology, PEF produced from industrial CO2 and biowastes could be a feasible and competitive substitute for PET and other materials. The renewable polyethylene furandicarboxylate (PEF) has potential to replace the fossil-based polyethylene terephthalate, but the energy-intensive production hinders wider adoption. This study shows that PEF from industrial CO2 emissions and non-food biomass can save 40.5% emissions and energy use.

Abstract The automotive industry is facing on-going challenges to improve the sustainability of its manufacturing processes and vehicle emission. Policies are one of the main drivers towards low-carbon manufacturing. In this work, the UK regulations in terms of environment, energy-efficiency and resources management and the ISO Standards concerning the automotive sector have been identified and described. The environmental benefits obtained in terms of energy consumption, waste production, water consumption, and air quality by a more efficient vehicle production for the UK manufacturers are presented. Current thermal energy management practice and strategies to increase the energy efficiency of the automotive manufacturing process are described. It is concluded that manufacturing processes and plants are both in need of modifications to achieve low-carbon manufacturing and produce low or zero emission vehicles.

AbstractFollowing the enforcement of MARPOL Annex VI Regulations for the Prevention of Air Pollution from Ships, retrofitting conventional power plants with emerging technologies is seen as a means to promote sustainability of marine transport and comply with more stringent emissions legislation. However, a knowledge gap exists as the environmental performance of retrofit power plant solutions incorporating emerging technologies has not been examined using an integrated system approach based on Life Cycle Assessment. The purpose of this research was to investigate if integrating selected emerging technologies i.e. photovoltaic systems, lithium-ion batteries, cold ironing and power-take-off/power-take-in systems supplemented by frequency converters and variable frequency drives into an existing power plant would be to the advantage of a chosen ship type i.e. Roll-on/Roll-off cargo ships, from the perspectives of resource consumption and environmental burden. Using the power plant of an existing vessel as a case study, it was found that cast iron, steel, copper and aluminium were the four materials most commonly consumed during manufacturing phase i.e. 2.9×105kg, 1.9×105kg, 5.3×104kg and 2.9×104kg respectively. By burning 2.9×107kg of heavy fuel oil and 2.3×108kg of marine diesel oil during operation, 8.2×108kg of carbon dioxide, 1.7×107kg of nitrogen oxides, 6.1×106kg of sulphur dioxide, 7.6×105kg of carbon monoxide, 6.5×105kg of hydrocarbon and 4.7×105kg of particulate matter would be released. Over a projected 30-year period, emissions released to air and freshwater were found to be significant. Based on 3 characterisation methodologies, ecotoxicity potential, with 7–10 orders of magnitude, was identified as the most significant environmental burden. Consuming and storing resources had the least impact, operating diesel engines and auxiliary generators had a moderate impact, and disposing metallic waste had the highest impact. The research concluded that the environmental burden caused by a marine power plant was significant but retrofitting existing power plant with suitable emerging technologies could reduce a number of impacts by 4–7 orders of magnitude, as verified via scenario analysis. However, the system should be designed and managed with due care as the environmental benefits, such as lower fuel consumption, emission reduction and performance improvement in some environmental measures are always achieved at the expense of an increase in other detrimental impacts.

The installed capacity, electricity generation from wind, and the curtailment of wind power in the UK between 2011 and 2021 showed that penetration levels of wind energy and the amount of energy that is curtailed in future would continue to rise whereas the curtailed energy could be utilised to produce green hydrogen. In this study, data were collected, technologies were chosen, systems were designed, and simulation models were developed to determine technical requirements and levelised costs of hydrogen produced and transported through different pathways. The analysis of capital and operating costs of the main components used for onshore and offshore green hydrogen production using offshore wind, including alternative strategies for hydrogen storage and transport and hydrogen carriers, showed that a significant reduction in cost could be achieved by 2030, enabling the production of green hydrogen from offshore wind at a competitive cost compared to grey and blue hydrogen. Among all scenarios investigated in this study, compressed hydrogen produced offshore is the most cost-effective scenario for projects starting in 2025, although the economic feasibility of this scenario is strongly affected by the storage period and the distance to the shore of the offshore wind farm. Alternative scenarios for hydrogen storage and transport, such as liquefied hydrogen and methylcyclohexane, could become more cost-effective for projects starting in 2050, when the levelised cost of hydrogen could reach values of about £2 per kilogram of hydrogen or lower.

The environmental impacts of producing biofuels from algae include not only climate change but also other impacts. Throughout the whole life cycle, neglecting any significant impacts and shifting any environmental burdens from one impact to another must be avoided. This chapter presents life cycle assessment as a tool for the purpose and existing literature on biofuels produced from algae, relevant LCA, and biofuel production facilities. It indicates that a far greater evidence base, methodological harmonization, and greater use of industrial data are required to allow LCA to become a truly valuable tool for the development of algae biofuels.