• Energy Research

Abstract Natural resources are not uniformly distributed over the landscape and, as a consequence, different areas support different social and economic development challenges. In this context, geo-referred information plays a paramount role in the dynamics of economies and their interaction with the environment. Synergic use of geographic information system (GIS), spatial planning (i.e. land use, urban, regional, and environmental planning) and emergy assessment may provide a very meaningful framework toward sustainability. Measuring resources in emergy terms means to quantify their environmental worth to all species in a given area: the integration of emergy and GIS allows the description of the spatial distribution of these resources and consequently the assessment of land's intrinsic environmental value, in support of land use planning policies. Thematic maps showing the distribution and environmental quality of renewable emergy flows (solar radiation, rainfall, wind, and geothermal heat) in Campania Region (Southern Italy) are presented in this work, all converging toward the generation of an annual renewable areal empower density (seJ ha−1 year−1) map. These maps are useful to identify the primary resource flows that are locally available in support of sustainable land use and production patterns. The main results show that natural areas have the highest annual renewable areal empower density (11.30E + 14 seJ ha−1 year−1) among all the different regional land use patterns, much higher than the average value of Campania Region (7.22E + 14 seJ ha−1 year−1). The 59.64% of the total annual renewable emergy converges to natural areas although they are only about 38.15% of the total regional land use. The proposed approach allows to classify regional areas according to their environmental value, thus providing useful policy information oriented toward supporting and conserving environmentally valuable land and natural resources.

Successful market penetration of Fuel Cell (FC) technologies requires increased research and technological efforts towards improved efficiency, durability, costs and environmental performance according to accepted standards. Life Cycle Assessment (LCA) can help understand to what extent FCs are environmentally sound, to what extent they can be improved and what steps and components require attention. A guidance manual for LCA application to FC technologies, processes and systems, compliant with the International Reference Life Cycle Data System (ILCD), was developed within the European Union-funded Fuel Cell-Hydrogen Guide (FC-Hy Guide) Consortium. The purpose was to provide entrepreneurs, consultants and experts with a specific guidance tool for use in policy context and decision-making. This paper presents the application of the FC-Hy Guide scheme to Molten Carbonate Fuel Cells (MCFC), with focus on the following aspects: (1) data quality; (2) information needed; (3) background and foreground data; (4) FC stack and balance of system; (5) improvement potential; (6) sensitivity of results and data uncertainty.

Abstract A comprehensive method of analysis based on energetic, exergetic, emergetic and economic evaluations is proposed in the paper and the application presented. The method is applied to selected energy conversion processes (hydroelectric and thermoelectric ones and bioethanol production). Results are presented and compared while general considerations about the effectiveness of the different approaches are suggested. Emissions to the environment are also evaluated. Suitable performance indicators developed within the proposed methodological framework are defined and discussed accordingly. The method proposed here is addressed to policy makers, operators and designers working in the field of energy supply and conversion. In the authors' opinion, by jointly applying and comparing all of the methods suggested in the paper, valuable information about plant performance and possible areas of improvement are obtained. This can be helpful in the decision-making process.

Abstract Although photovoltaic (PV) technology has been projected as one of the most promising candidates to replace conventional fossil based power generation, claims about the potential disadvantages of the PV panels end-of-life (EoL) deserve careful attention in order to fully establish a feasibility and viability baseline and support technological and implementation policies. The current challenge concerning PV technology resides in making them efficient and competitive in comparison with traditional power generation systems, without disregarding the appraisal of EoL impacts. The emergy analysis method proved to be a reliable approach for the evaluation of the efficiency, effectiveness and environmental friendliness of technological processes under a global scale perspective and may likely be applied to the EoL PV investigation as a complement of conventional energy and economic assessments. Therefore, this method was used in this study to evaluate the sustainability of a PV panel recycling process. In addition, this paper aims to explore the implications of methodological assumptions when Emergy Accounting (EMA) tackles waste management systems, in order to address the shortcomings in this field. Results show that the PV panel treatment can generate large environmental benefits not only at the local scale of the process, but also at the larger scale of the industrial manufacture and material recovery, as well as at the even larger scale of the biosphere where resources come from and pollution is released. The comparison between the emergy invested for electricity production via PV and fossil energy sources also including EoL resource and environmental costs, highlights that PV technology is competitive under both energy and environmental points of view. This comparison reveals that the solar technologies imply remarkable emergy savings (1.45E+12 sej/kWh for fossil sources versus 3.57E+11 sej/kWh for crystalline silicon photovoltaic down to 2.31E+11 sej/kWh for cadmium telluride photovoltaic). Results clearly show that PV solar power can be considered a mature technology and can favorably compete with other renewable and non-renewable options for electricity generation. However, efficiency improvements of PV panels thermal recovery are still possible and may lead to further decrease of still too large emergy costs of the treatment process, not to talk of potential recovery alternatives such as chemical treatment for silicon cells and better upstream industrial design.

Abstract This paper provides a reference set of indices based on emergy, for the evaluation of ecotechnological processes and whole economies. Indices of emergy yield ratio (EYR), environmental loading ratio (ELR), and emergy investment ratio (EIR), among others, are stressed, and a new index the emergy sustainability index (ESI) is defined. The emergy indices for a given system are shown to be functions of renewable, nonrenewable and purchased emergy inflows. Indices are given for several ecological engineering activities including oil spill restoration, land reclamation and wastewater recycle through wetlands, several production systems, and several national economies to demonstrate their usefulness. Ecological engineering involves both natural and engineered systems and the flows of renewable and nonrenewable energy, the appropriate amounts of which are important to determine if they are to result in sustainable use of resources. The sustainability index can be used to evaluate appropriate nonrenewable investments in eco-technology to maximize their performance. Sustainability of economies is shown to be a function of the net yield of the economy and its `load' on the environment. The trends of these indices can be monitored over time and provide useful information about the dynamics of economic systems within the carrying capacity of the environment in which they develop. When a particular sector or production process is focused on, instead of a national economy, emergy based indices can provide insights into the thermodynamic efficiency of the process, the quality of its output, and the interaction between the process and its surrounding environment.

The Belt and Road Initiative (BRI) is a central policy within China's regional development and foreign trade strategy. Traditional trade has typically depended on economic valuation of resources, while the embedded environmental value is rarely considered. This situation exists in most BRI trade evaluations. To address BRI environmental sustainability issues, we consider the role of pivotal Chinese provinces and their key trade partners (ASEAN countries) as an illustration for the environmental value of resource exchanges. Emergy accounting is used as the valuation tool for a sample period of seventeen years. Key results include: (1) Emergy valuations show sustainability of sample provinces decreased over time; (2) ASEAN countries such as Indonesia, Malaysia, Singapore, Thailand, and Vietnam play significant resource roles for provincial economic systems; (3) Diverse trends in trade between pivotal provinces and ASEAN countries resulted in an unbalanced trade structure from trade. Policy implications are proposed to promote a more globally sustainable and fair trade using BRI as an established trade policy.

Abstract Industrial parks have been adopted as one way to promote industrial development in China since the early 1980s. However, most of current performance evaluation indicators highlight the maximization of industrial yield, leading to both ecological degradation and environmental pollution due to intensive industrial activities. Therefore, it is critical to develop appropriate evaluation indicators so that industrial parks can move toward sustainable development. This paper aims to fill such a research gap by developing innovative emergy indicators. Kaya formula and index decomposition analysis (IDA) were integrated together in order to quantify the key factors influencing the sustainability of an industrial park. Tianjin Economic Development area (TEDA), the largest industrial park in terms of its economic scale in China, was chosen as one case study area for testing the related methods. The results show that during the period of 2006–2010 the sustainability of TEDA experienced a declining trend. From the Kaya formula and IDA analysis, indicators on economic efficiency of process, economic return on investment, renewable empower density and nonrenewable empower density were calculated. Such research findings provide valuable policy insights to the industrial park managers so that they can prepare appropriate development strategies for achieving sustainable development of their industrial parks by considering the local realities.

Green hydrogen (GH2) is expected to play an important role in future energy systems in their fight against climate change. This study, after briefly recalling how GH2 is produced and the main steps throughout its life cycle, analyses its current development, environmental and social impacts, and a series of case studies from selected literature showing its main applications as fuel in transportation and electricity sectors, as a heat producer in high energy intensive industries and residential and commercial buildings, and as an industrial feedstock for the production of other chemical products. The results show that the use of GH2 in the three main areas of application has the potential of contributing to the decarbonization goals, although its generation of non-negligible impacts in other environmental categories requires attention. However, the integration of circular economy (CE) principles is important for the mitigation of these impacts. In social terms, the complexity of the value chain of GH2 generates social impacts well beyond countries where GH2 is produced and used. This aspect makes the GH2 value chain complex and difficult to trace, somewhat undermining its renewability claims as well as its expected localness that the CE model is centred around.

Agriculture is expected to provide food in a sustainable manner while also partially contributing to the energy problem as well as to bio-material supply. Moreover, fossil fuels scarcity calls for an increase of energy efficiency in agricultural processes. This study evaluates patterns, trends, driving factors and trade-offs of energy use in selected agricultural systems and aims at grouping them into clusters with similar energy and social performances. Results show that in 2010 the highest power densities and energy intensities of production are found by crop sector of cluster 5 (China: 59.19 GJ/ha, 15.29 MJ/kg dm) and cluster 3 (Japan: 50.11 GJ/ha, 12.32 MJ/kg dm) as well as by livestock sector of cluster 3 (Japan: 328.47 GJ/ha, 103.08 MJ/kg dm), while the lowest values in clusters 2 and 4, including selected developing countries and USA. Cluster 3 (Japan) also shows the lowest energy intensity of economic value of crops (2.75 MJ/$), while cluster 5 (China) the highest one (23.96 MJ/$). Cluster analysis also sheds light on trends, identifying two groups: cluster 1*, gathering most European countries, USA and Japan, characterized by a decreasing trend of all energy indicators; and cluster 2*, including developing countries, the Netherlands and Spain, characterized by an increasing trend of indicators. Results highlight the importance of an integrated framework for evaluating energy use as well as of a multi-criteria approach to understand the trade-offs and interplay of performance indicators.