Pathways for sustainable energy transition

Abstract

Energy transitions are ongoing processes all over the world. While sustainable solutions are envisioned for the future, many societies are still under high-carbon and high-pollution energy regime borne by fossil fuels. How to design pathways towards sustainable energy transition has attracted worldwide concerns. Understanding the possible transition pathways of the energy system requires the integration of new energy technologies, environmental sciences, economics and management. This Special Issue of Journal of Cleaner Production targets to collect the latest research results on sustainable energy systems, discover innovative avenues and inspiring models and share knowledge on energy system modelling and management. In this paper, we identify 4 themes on sustainable energy transition pathways including: (1) Sustainable energy economics and management; (2) Renewable energy generation and consumption; (3) Environmental impacts of energy systems; and (4) Electric vehicle and energy storage. Theories, technologies, innovative models, and successful experiences are discussed accordingly. It is suggested that creative, robust and audacious strategies in governance, management and education are needed to boost sustainable energy transition across various scales and sectors.

Introduction

Energy is critical to economic development and human's welfare, and is also inextricably linked to the challenges of sustainable development (Mundaca et al., 2018). With growing concerns on energy security and climate change, sustainable energy transition has attracted worldwide attentions. The history of energy transitions has been traced in the last ten years (Smil, 2010), those in European countries (Gales et al., 2007, Allen, 2009, Kander et al., 2013) and the U.S. (Jones, 2014). Although empirical studies and conceptual frameworks have advanced our knowledge of how the transformation of energy systems takes place, the global energy transition is still underway, from traditional biomass energy to modern commercial energy (such as electricity) and new renewable energy (such as wind and solar energy). The energy transition is pushing the frontiers in energy modelling, not only with new technologies, but also towards frameworks capable of representing the interdependencies between policy making, energy infrastructure expansion, market behavior, environmental impact and supply security (del Granado et al., 2018). The sustainable energy transition is not just a shifting to a new and high-efficiency energy system, but also a challenge in terms of making sure the environmental and social costs, risks and benefits of that shift are well managed in a way that can be considered sustainable (Sareen and Haarstad, 2018).

Exploring possible pathways for sustainable energy transition requires interdisciplinary knowledge concerning advanced technologies that drive the transition (Child et al., 2018), e.g., renewable energy, energy storage, waste to energy, electric vehicles, and energy efficient technologies. Of the emerging technologies, renewable energy, energy storage and battery, and electric vehicles are the most popular and representative ones that are closely related to our daily life. Renewable electricity generation (excluding hydro) was estimated to account for 8.4% of global electricity generation in 2017 (BP, 2018). Renewables do play a significant role in the growth of electricity, contributing almost 50% of the growth in global power generation. Many researchers suggested using renewable energy as an alternative for fossil fuels. Yang and Chen (2013) concluded that wind power is an economically feasible alternative for fossil fuel-based power generation. The penetration of wind power can bring substantial environmental emission alleviation co-benefits in the whole power generation sector (Yang et al., 2017). Comello et al. (2018) also suggested that solar power is positioned to constitute a significant and growing share of the energy mix. With more and more attentions focused on renewable energy materials and technologies (such as Jaouen et al., 2011, Mishra and Baeuerle, 2012) and renewable energy policies (e.g., Zhao et al., 2014, Kilinc-Ata, 2016; Cullen, 2017), a realizable renewable energy future pointed by Turner (1999) is coming true gradually. Electric vehicle, a basic unit of sustainable transport system, has been widely used to limit greenhouse-gas emissions and reduce petroleum use. Considerable efforts have been made to reduce vehicle and battery costs and improve operation performance. For example, Xiong et al., 2018a, Xiong et al., 2018b, Xiong et al., 2018c, Xiong et al., 2018d did a series of work towards a smarter battery management system used in electric vehicles. Zhang et al. (2018a) proposed a new technology to predict the remaining useful life of lithium-ion batteries to assess the battery reliability and mitigate battery risk. Hiermann et al. (2019) introduced a hybrid genetic algorithm to optimize the vehicle routing. However, there are still remaining challenges that preclude the large-scale application of renewable energy power and electric vehicle. For example, wind and solar energy are intermittent and depend on local meteorological conditions and power transmission, which cannot be used for steady power supply (Notton et al., 2018, Zhou et al., 2018). The operation and maintenance of renewable energy generation equipment is another challenge as its design life is usually shorter than the service life (Li and Chen, 2013, Zhang et al., 2018c). In terms of electric vehicle, the relatively limited capacity of batteries considerably reduces the operational range of electric vehicles (Hiermann et al., 2019). To overcome these technological barriers, cutting-edge technologies are urgently needed to promote the prosperity of new energy technologies.

Energy, resource and environmental impacts are interlinked. The focus of energy transition should not be limited to assessing certain technologies, or studying isolated components and factors of the energy system (del Granado et al., 2018). With the growing concerns on energy related environmental pollution and ecosystem degradation, the research and development of eco-environmental governance should be addressed to provide clean and sustainable transition solutions at each level of the concerned systems (Chen, 2015, Chen, 2016, Chen and Lu, 2015). Many studies have investigated the carbon emission, water consumption, and environmental impacts related to energy systems using different assessment and modelling tools such as exergetic analysis (Chen et al., 2014), life cycle assessment (Yang and Chen, 2014), input-output analysis (Fang and Chen, 2018), and data envelopment analysis (Wang C. et al., 2018). As environmental accounting and evaluation of energy systems are the basis for the design and optimization of sustainable energy system from both micro and macro level, tools for environmental modelling should be improved to increase the accuracy and robustness. Deepening environmental modelling studies may unveil a broader picture of the energy-environment nexus system, which can foster collaborative management to achieve both the targets of energy saving and emission reduction.

Without a managerial framework and a well-designed energy market to tackle the energy question, numerous new technologies for energy efficiency improvement and renewable integration will not gain the momentum required. There are two main perspectives of energy-economic nexus: the energy-income perspective and the energy-economic growth perspective. The former is represented by the environmental Kuznets curve approach. Suri and Chapman (1998) examined the EKC hypothesis considering commercial energy use and environmental consequences. Soytas et al. (2007) investigated the Granger causality relationship between income, energy consumption, and carbon emissions. However, Stern (2004) stated that the EKC results have a very flimsy statistical foundation. The true relations between income and the environmental issues should be disentangled using new decomposition and efficient frontier models. As summarized by Ozturk (2010), the energy-economic growth perspective focused on bidirectional causality between energy consumption and economic growth in both the short- and long-run. The empirical studies conducted mainly focus on testing the role of energy in stimulating economic growth or examining the direction of causality between these two variables (Apergis and Payne, 2011, Apergis and Payne, 2012, Fullerton and Walke, 2019, Murad et al., 2019). However, there is no consensus neither on the existence nor on the direction of causality between energy consumption and economic growth. New approaches and perspectives at different intervals of time should be developed (Ozcan and Ozturk, 2019). The effect of the most commonly used economic instruments for energy system regulation, such as loan (Gholz et al., 2017, Tonn and Berry, 1986, Zhao et al., 2012), energy taxation (Freire-González and Puig-Ventosa, 2019, Wolfson and Koopmans, 1996) and subsidy (Barkhordar et al., 2018, Pani and Perroni, 2018) have been extensively assessed. There also emerge models for designing possible pathways for sustainable energy transition from a macro perspective, such as computable general equilibrium model (Sue Wing, 2006), the Integrated MARKAL-EFOM3 System (Böhringer and Rutherford, 2008), granger causality (Kraft and Kraft, 1978, Wolde-Rufael, 2004), cointegration (Ang, 2008, Lise and Van Montfort, 2007), multivariate VAR model (Stern, 1993), error correction model (Altinay and Karagol, 2004), and autoregressive distributed lag model (Odhiambo, 2009). Enriching energy-economic nexus modelling frameworks may allow to better investigate added-value insights from modelling the interactions between the main layers, sectors, and components of the energy-economic system and shed light on economically sound energy policies (del Granado et al., 2018).

The aim of this Special Issue is to present a problem-oriented forum transcending disciplinary boundaries and explore advanced technologies and new methodologies for an integrated vision of sustainable energy transition pathways. Totally 25 papers are collected in this issue to address a variety of energy science and technological issues and environmental policy implications as well, including (1) Sustainable energy economics and management; (2) Renewable energy generation and consumption; (3) Environmental impacts of energy systems; and (4) Electric vehicle and energy storage.