• Energy Research
• 12. Responsible consumption close
• US close
• ES close
• Aurora Universities Network close

Abstract In recent years, distributed energy systems (DESs) have been recognized as a promising option for sustainable development of future energy systems, and their application has increased rapidly with supportive policies and financial incentives. With growing concerns on global warming and depletion of fossil fuels, design optimization of DESs through economic assessments for short-run benefits only is not sufficient, while application of exergy principles can improve the efficiency in energy resource use for long-run sustainability of energy supply. The innovation of this paper is to investigate exergy in DES design to attain rational use of energy resources including renewables by considering energy qualities of supply and demand. By using low-temperature sources for low-quality thermal demand, the waste of high-quality energy can be reduced, and the overall exergy efficiency can be increased. The goal of the design optimization problem is to determine types, numbers and sizes of energy devices in DESs to reduce the total annual cost and increase the overall exergy efficiency. Based on a pre-established DES superstructure with multiple energy devices such as combined heat and power and PV, a multi-objective linear problem is formulated. In modeling of energy devices, the novelty is that the entire available size ranges and the variation of their efficiencies, capital and operation and maintenance costs with sizes are considered. The operation of energy devices is modeled based on previous work on DES operation optimization. By minimizing a weighted sum of the total annual cost and primary exergy input, the problem is solved by branch-and-cut. Numerical results show that the Pareto frontier provides good balancing solutions for planners based on economic and sustainability priorities. The total annual cost and primary exergy input of DESs with optimized configurations are reduced by 21–36% as compared with conventional energy supply systems, where grid power is used for the electricity demand, and gas-fired boilers and electric chillers fed by grid power for thermal demand. A sensitivity analysis is also carried out to analyze the influence of energy prices and energy demand variation on the optimized DES configurations.

The progressive geography of climate change impacts places the African continent among the most vulnerable regions of the world. In line with the prediction of the Intergovernmental Panel on Climate Change in its first report (1990), the involuntary migration of population is already proving to be one of the most serious of such impacts across the region. The overwhelming majority of victims remain within their own countries. Therefore, coupled with conflict, violence and development projects, slow-onset and rapid-onset disasters have currently made Africa home to the largest number of internally displaced people. Determined to tackle this plight, on 23rd October 2009 the African Union adopted its Convention for the Protection and Assistance of Internally Displaced Persons in Africa (Kampala Convention), articulating the need for a holistic response based on a combined framework of international human rights law and international humanitarian law. Five years since the convention entered into force (on 6th December 2012), this paper aims to taking stock of the progress made in its implementation and, in particular, assessing its effectiveness in protecting people environmentally displaced in the context of climate change. To this end, it identifies the existing and ongoing normative, policy and institutional processes on domestication and implementation of the convention and explores the degree to which these processes provide for the protection due to people displaced by environmental disasters, specially those slow-onset (e.g. desertification). The paper finds that, despite the remarkable efforts towards the implementation of the said convention, the concrete impact of its provisions on enhancing the protection of and assistance to environmental IDPs is still unperceiv

A continuous growth of international trade, especially between developing countries, has greatly increased carbon dioxide (CO2) emissions associated with energy consumption over the past two decades. Given the more intensified intraregional cooperation and trade within the Belt and Road Initiative (BRI), this study aims to trace the imbalance of CO2 embodied in trade between nations in BRI and the rest of the world, providing new insights into the drivers of emissions growth by contrasting consumption, production and technological differences-based perspectives. Results indicate that the BRI contributed to over 50% of global carbon footprint and 92% of its increase in 1995–2015. The BRI was a net exporter of trade-embodied emissions, whose technological-adjusted carbon footprint remained remarkably large due to comparatively high carbon intensity. Geographically, carbon leakage has gradually moved from China and India to other BRI countries, especially to Southeast Asia, West Asia and Africa. Technological change was the key driver of emissions reduction, followed by the change in industrial structure. The growth in final demand per capita was the most important driver for the growth of CO2 emissions in BRI. Improving carbon efficiency remains a critical step for BRI nations to slow down not only emissions growth but also carbon leakage. The paper managed to provide novel insights into the carbon leakage in BRI by contrasting the consumption, production and technological differences-based perspectives, thus being able to better inform policymakers on region-specific low-carbon transition and global climate governance.

The development of renewable energy sources has been primarily justified on the ground of environmental policies and energy security, but new jobs opportunities and establishment of new economy sectors may be equally important co-benefits from investments in this sector. The main goal of this paper is to assess the employment benefits of investments in renewable energy in the Czech Republic. We examine the level and rate of the development of the renewable energy sector in the Czech Republic in terms of ('green‘) job creation for the period 2008–2013, in comparison to data from other EU countries, including Germany as a leading early investor in renewables. Whilst the deployment of renewable energy in the Czech Republic has succeeded to create a significant number of jobs (more than 20 000 employees in 2010), our analysis illustrates a strong dependency of job creation on the continuation of financial incentives. We also find that biomass and waste energy processing offer the highest employment per MWh, which benefits employment in (economically fragile) rural areas. We discuss the question of competitiveness of a country that was not amongst the early adopters of renewables, arguing that the technical skills of the labour force in the Czech Republic provide a potential for more sustained investments in the sector.

In the present article, the thermodynamic potential of a sustainable plasma-assisted nitrogen fixation process for co-production of ammonia and hydrogen is investigated. The developed process takes advantage of chemical looping system by using a liquid metal such as gallium to drive nitrogen fixation reaction using three reactors including reactor R1 to produce gallium nitride from gallium and nitrogen, reactor R2 to produce ammonia and hydrogen from gallium nitride, and plasma reactor R3 to convert gallium oxide to pure gallium. The results of the thermodynamic assessments showed that the proposed reactions are spontaneous and feasible to occur in the reactors. Likewise, the first two reactions are exothermic with ΔH=-230[Formula presented] and ΔH=-239[Formula presented] in the reactors R1 and R2, respectively with an equilibrium chemical conversion of 100%. The plasma reactor requires thermal energy to drive an endothermic reaction of gallium oxide dissociation withΔH=+870[Formula presented]. Thermochemical equilibrium analysis showed that the molar ratio of steam to GaN, as well as the operating pressure and temperature of reactor R2 are the main operating parameters identifying the product composition in the reactor such that by increasing the temperature, the molar ratio of hydrogen to ammonia increases. However, by increasing the molar ratio of steam/GaN (φ value) from 0.1 to 1, the hydrogen content of the reactor increases from 45% to 70% at 400 °C. For φ > 1.0, the hydrogen content decreases while more hydrogen participate in the formation of NH3 thereby increasing the mole fraction of ammonia in the reactor. The equilibrium chemical conversion of all three reactors is expected to reach the completion point (χ = 100%) due to the highly negative Gibbs free energy of the liquid metal-based reactions together with a large thermal driving force supported by thermal plasma reactor. Finally, a scalability study points at a possible use of the new disruptive process design at small scale, and possible industrial transformation scenarios for a distributed production at a local site of consumption are depicted.

The development of a sustainable bio-based economy has drawn much attention in recent years, and research to find smart solutions to the many inherent challenges has intensified. In nature, perhaps the best example of an authentic sustainable system is oxygenic photosynthesis. The biochemistry of this intricate process is empowered by solar radiation influx and performed by hierarchically organized complexes composed by photoreceptors, inorganic catalysts, and enzymes which define specific niches for optimizing light-to-energy conversion. The success of this process relies on its capability to exploit the almost inexhaustible reservoirs of sunlight, water, and carbon dioxide to transform photonic energy into chemical energy such as stored in adenosine triphosphate. Oxygenic photosynthesis is responsible for most of the oxygen, fossil fuels, and biomass on our planet. So, even after a few billion years of evolution, this process unceasingly supports life on earth, and probably soon also in outer-space, and inspires the development of enabling technologies for a sustainable global economy and ecosystem. The following review covers some of the major milestones reached in photosynthesis research, each reflecting lasting routes of innovation in agriculture, environmental protection, and clean energy production.

Sustainable Development Goals and the Paris Agreement stand as milestone diplomatic achievements. However, immense discrepancies between political commitments and governmental action remain. Combined national climate commitments fall far short of the Paris Agreement's 1.5/2°C targets. Similar political ambition gaps persist across various areas of sustainable development. Many therefore argue that actions by nonstate actors, such as businesses and investors, cities and regions, and nongovernmental organizations (NGOs), are crucial. These voices have resonated across the United Nations (UN) system, leading to growing recognition, promotion, and mobilization of such actions in ever greater numbers. This article investigates optimistic arguments about nonstate engagement, namely: (a) “the more the better”; (b) “everybody wins”; (c) “everyone does their part”; and (d) “more brings more.” However, these optimistic arguments may not be matched in practice due to governance risks. The current emphasis on quantifiable impacts may lead to the under‐appreciation of variegated social, economic, and environmental impacts. Claims that everybody stands to benefit may easily be contradicted by outcomes that are not in line with priorities and needs in developing countries. Despite the seeming depoliticization of the role of nonstate actors in implementation, actions may still lead to politically contentious outcomes. Finally, nonstate climate and sustainability actions may not be self‐reinforcing but may heavily depend on supporting mechanisms. The article concludes with governance risk‐reduction strategies that can be combined to maximize nonstate potential in sustainable and climate‐resilient transformations.This article is categorized under: Policy and Governance > Multilevel and Transnational Climate Change Governance