• Energy Research
• 2021-2025close
• engineering and technology close
• DE close

Abstract With the rapid advancement in wearable electronics, energy harvesting devices based on triboelectric nanogenerators (TENGs) have been intensively investigated for providing sustainable power supply for them. However, the fabrication of wearable TENGs still remains great challenges, such as flexibility, breathability and washability. Here, a route to develop a new kind of woven-structured triboelectric nanogenerator (WS-TENG) with a facile, low-cost, and scalable electrospinning technique is reported. The WS-TENG is fabricated with commercial stainless-steel yarns wrapped by electrospun polyamide 66 nanofiber and poly(vinylidenefluoride-co-trifluoroethylene) nanofiber, respectively. Triggered by diversified friction materials under a working principle of freestanding mode, the open-circuit voltage, short-circuit current and maximum instantaneous power density from the WS-TENG can reach up to 166 V, 8.5 µA and 93 mW/m2, respectively. By virtue of high flexibility, desirable breathability, washability and excellent durability, the fabricated WS-TENG is demonstrated to be a reliable power textile to light up 58 light-emitting diodes (LED) connected serially, charge commercial capacitors and drive portable electronics. A smart glove with stitched WS-TENGs is made to detect finger motion in different circumstances. The work presents a new approach for self-powered textiles with potential applications in biomechanical energy harvesting, wearable electronics and human motion monitoring.

Bioplastics are alternatives of conventional petroleum-based plastics. Bioplastics are polymers processed from renewable sources and are biodegradable. This study aims at conducting an environmental impact assessment of the bioprocessing of agricultural wastes into bioplastics compared to petro-plastics using an LCA approach. Bioplastics were produced from potato peels in laboratory. In a biochemical reaction under heating, starch was extracted from peels and glycerin, vinegar and water were added with a range of different ratios, which resulted in producing different samples of bio-based plastics. Nevertheless, the environmental impact of the bioplastics production process was evaluated and compared to petro-plastics. A life cycle analysis of bioplastics produced in laboratory and petro-plastics was conducted. The results are presented in the form of global warming potential, and other environmental impacts including acidification potential, eutrophication potential, freshwater ecotoxicity potential, human toxicity potential, and ozone layer depletion of producing bioplastics are compared to petro-plastics. The results show that the greenhouse gases (GHG) emissions, through the different experiments to produce bioplastics, range between 0.354 and 0.623 kg CO2 eq. per kg bioplastic compared to 2.37 kg CO2 eq. per kg polypropylene as a petro-plastic. The results also showed that there are no significant potential effects for the bioplastics produced from potato peels on different environmental impacts in comparison with poly-β-hydroxybutyric acid and polypropylene. Thus, the bioplastics produced from agricultural wastes can be manufactured in industrial scale to reduce the dependence on petroleum-based plastics. This in turn will mitigate GHG emissions and reduce the negative environmental impacts on climate change.

With the recent advancements in power electronics for wind turbines (WTs) and increasing penetration of wind energy, wind power plants (WPP) have become necessary contributors of reactive power support for the bulk power system. Balancing reactive power support with individual WT operating requirements in a cost-effective manner is a challenge for WPP designers. In this paper, we present a methodology to optimize the WPP reactive power capability as seen from the point of common coupling (PCC), accounting for steady-state operating capabilities of the WPP equipment. Thus, the proposed methodology determines the configuration of the tap-changing transformers within the WPP that maximizes the amount of reactive power the WPP can either consume or inject to the network, considering uncertain levels of wind power generation and voltage magnitudes at the PCC. The optimized reactive power capability (ORPC) problem is initially formulated as a mixed-integer nonlinear programming (MINLP) model. Then, a set of efficient linearization techniques are used to obtain a mixed-integer linear programming (MILP) model that can be solved via off-the-shelf mathematical programming solvers. Results demonstrate that the proposed MILP model is a scalable, flexible and accurate method to maximize the reactive power capability of WPP.

This paper contains the results of research on a large assemblage of jumping spiders collected by J.-C. Ledoux from Ivory Coast in 1974–75. In total, 105 species are included. Three new genera are erected Pulcherula gen. nov., Sphericula gen. nov. and Vicirionessa gen. nov. Two generic names are synonymized, Polemus Simon, 1902 with Baryphas Simon, 1902 and Brancus Simon, 1902 with Thyene Simon, 1885. Twenty eight new species are described: Afraflacilla albopunctata sp. nov. (♀), Ansienulina lamottei sp. nov. (♂), Asemonaea pusilla sp. nov. (♀), Detalik cavally sp. nov. (♀), Evarcha zougoussi sp. nov. (♀), Heliophanus (Heliophanus) minimus sp. nov. (♂♀), Hyllus ignotus sp. nov. (♀), Hyllus solus sp. nov. (♀), Hyllus unicolor sp. nov. (♀), Icius bandama sp. nov. (♂♀), Langona recta sp. nov. (♂), Malizna zabkai sp. nov. (♀), Menemerus niangbo sp. nov. (♀), Myrmarachne galea sp. nov. (♀), Phintella brevis sp. nov. (♂), Phintella globosa sp. nov. (♀), Phintella occidentalis sp. nov. (♂), Phintella transversa sp. nov. (♂), Pochytoides mirabilis sp. nov. (♂♀), Pochytoides tonkoui sp. nov. (♀), Pochytoides tournieri sp. nov. (♂), Pulcherula magna gen. et sp. nov. (♂), Rhene ferkensis sp. nov. (♀), Sonoita ledouxi sp. nov. (♂♀), Sphericula globulifera gen. et sp. nov. (♀), Thiratoscirtus silvestris sp. nov. (♂♀), Tusitala bandama sp. nov. (♀) and Tusitala cornuta sp. nov. (♂). Five specific names are synonymized: Polemus chrysochirus Simon, 1902 with Baryphas jullieni Simon, 1902, Viciria mondoni Berland & Millot, 1941with Malloneta guineensis Simon, 1902, Brancus lacrimosus Wesołowska & Edwards 2008 with Vicirionessa fuscimana (Simon, 1903), Viciria monodi Berland & Millot, 1941 and Viciria equestris pallida Berland & Millot, 1941 with Vicirionessa equestris (Simon, 1903). Hyllus natali peckhamorum Berland & Millot, 1941 is removed from synonymy of Hyllus brevitarsis Simon, 1902, revalidated and its rank is raised as Hyllus peckhamorum Berland & Millot, 1941 stat. nov. Also rank of Telamonia aequipes minor Lessert, 1925 is elevated as Phintella minor (Lessert, 1925) stat. nov. Menemerus dubius Berland & Millot, 1941 is removed from nomina dubia. This species is considered valid and is redescribed. A lectotype is designated for it. The male of Mexcala torquata Wesołowska, 2009 and females of Hyllus tuberculatus Wanless & Clark, 1975, Iranattus principalis (Wesołowska, 2000), Myrmarachne eidmanni Roewer, 1942 and Thiratoscirtus tentativus (Szűts & Jocqué, 2001) are described for the first time. Many new combinations are proposed. Twenty ex Brancus are recombined: Hyllus nigeriensis (Wesołowska & Edwards, 2012) comb. nov., Thyene blaisei (Simon, 1902) comb. nov., Thyene calebi (Kanesharatnam & Benjamin, 2018) comb. nov., Thyene mutica (Simon, 1902) comb. nov., Thyene verdieri (Berland & Millot, 1941) comb. nov., Vicirionessa besanconi (Berland & Millot, 1941) gen. et comb. nov., Vicirionessa fuscimana (Simon, 1903) gen. et comb. nov., Vicirionessa mustela (Simon, 1902) gen. et comb. nov., Vicirionessa niveimana (Simon, 1902) gen. et comb. nov., Vicirionessa occidentalis (Wesołowska & Russell-Smith, 2011) gen. et comb. nov., Vicirionessa peckhamorum (Lessert, 1927) gen. et comb. nov., Vicirionessa signata (Dawidowicz & Wesołowska, 2016) gen. et comb. nov. Four ex Viciria are recombined: Vicirionessa chabanaudi (Fage, 1923) gen. et comb. nov., Vicirionessa equestris (Simon, 1903) gen. et comb. nov., Vicirionessa prenanti (Berland & Millot, 1941) gen. et comb. nov., Vicirionessa tergina (Simon, 1903) gen. et comb. nov. and one species ex Hyllus: Vicirionessa albocincta (Thorell, 1899) gen. et comb. nov. Furthermore, the following two new combinations are proposed: Thiratoscirtus tentativus (Szűts & Jocqué, 2001) comb. nov. (ex Bacelarella) and Baryphas galeatus (Simon, 1902) comb. nov. (ex Polemus). For 11 species known so far from single records new data are presented: Heliophanus butemboensis Wesołowska, 1986, Hyllus lwoffi Berland & Millot, 1941, Hyllus tuberculatus Wanless & Clark, 1975, Menemerus dubius Berland & Millot, 1941, Mexcala torquata Wesołowska, 2009, Neaetha maxima Wesołowska & Russell-Smith, 2011, Pachyballus miniscutulus Wesołowska, Azarkina & Wiśniewski 2020, Phintella paludosa Wesołowska & Edwards, 2012, Thiratoscirtus gambari Wesołowska & Russell-Smith, 2011, Tusitala guineensis Berland & Millot, 1941 and Tusitala lutzi Lessert, 1927.

AbstractThermochemical biorefineries for the production of chemicals and materials can play an important role in the bioeconomy. However, their economic viability is often questioned under the premise of the economy of scale. This paper presents a regional, modular biorefinery concept for the production of the platform chemicals hydroxymethylfurfural (HMF), furfural and phenols from the lignocellulosic perennial miscanthus, which can be cultivated on marginal and degraded areas. The paper focuses on the question of the minimum selling price of HMF and the optimal plant size for this purpose, using the region of Baden‐Württemberg, Germany, as an example. Based on small pilot plant results, a scalable process simulation was created via AspenPlus. This allows different scenarios and process combinations of this multi‐output biorefinery concept to be compared with each other. Using this, a minimum sales price for the main product HMF is calculated using methods of dynamic investment cost calculation according to the net present value method. Based on this, the plant capacity was scaled. The scenarios and sensitivity analyses show that, with an accuracy of ±15%, regional biorefineries could already offer platform chemicals at prices of 2.21–2.90 EUR/kg HMF at the current stage of development. This corresponds to three to four times the price of today's comparative fossil base chemicals and is thus a competitive option from the authors’ point of view. The local biomass and the heat prices were identified as the main influencing factors. As a result, the selection of the location will have a decisive influence on the economic viability of such concepts in the case of further development and optimization of the process in first demonstration plants.

This paper aims to fill a research gap in the area of consumer-citizen attitudes to business models for decentralized energy storage, at the level of households and buildings. The study focuses on the interaction of such attitudes and their underlying motivation factors with socio-cultural, contextual factors. Self-determination theory (SDT) is used as a theoretical framework, to connect interpersonal and contextual factors, addressing the question of how contexts influence the motivation to support energy storage. Drawing on SDT, this study examines the role of autarky (independence from the energy system), autonomy (control over energy management) and relatedness (degree of sharing required) in this regard, embedded and interpreted in the socio-cultural local context of two demonstration sites in Sweden and Portugal. A mixed method approach is used. Quantitative survey data provides information on local social and cultural dimensions, followed by stakeholder consultation workshops that elicit participants’ views on different models of decentralized energy storage. The findings raise questions of how to improve autarky and autonomy for prosumers, while keeping the need for time investment low and provide flexibility regarding the required degree of interaction between prosumers. Implications for business models and policy support for citizen-centered sustainable urban energy systems are derived.