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Abstract In the next 25 years an unprecedented number of new marine artificial structures, over 75,000 offshore wind turbines alone, are planned to meet global net zero targets. Structures are required to last for multiple decades in the hostile marine environment; where the largest cost across their whole lifecycle is on operations and maintenance dependent on accessibility in calm seas. However, the role of climate change on accessibility, and thus operational cost, has not been resolved. Here we provide the first study of future accessibility; evaluated from global climate model driven wave modelling, using the high emission scenario (RCP8.5). We found that climate change drives significant regional variation in accessibility, with the northern hemisphere benefiting from a 6% increase in operating windows whilst accessibility in parts of the southern hemisphere is reduced by 6-9%. These findings will help offshore developers and stakeholders incorporate adaptions to climate change as part of strategic planning practices.

This paper presents a comparative study in predicting the monthly average solar radiation for Darwin, Australia (latitude 12.46 deg S longitude 130.84 deg E). The city of Darwin, Northern Territory (NT), has the highest and most consistent sunshine duration among all the other Australian states. This unique climate presents an opportunity for photovoltaic (PV) applications. Reliable and accurate predictions of solar radiation enable potential site locations, which exhibit high solar radiations and sunshine hours, to be identified for PV installation. Three predictive models were investigated in this study—the linear regression (LR), Angstrom–Prescott–Page (APP), and the artificial neural network (ANN) models. The mean global solar radiation coupled with the climate data (mean minimum and maximum temperatures, mean rainfall, mean evaporation, and sunshine fraction) obtained from the Australian Bureau of Meteorology (BoM) formed the basis of the dataset. Using simple and easily obtainable climate data presents an added advantage by reducing model complexity. Predictive results showed the root mean square errors (RMSEs) obtained were 6.72%, 13.29%, and 8.11% for the LR, APP, and ANN models, respectively. The predicted solar exposure from the LR model was then compared with the satellite-derived data to assess the accuracy of the LR method.

A natural holm oak forest was selectively thinned to test thinning as a tool to reduce tree mortality, increase productivity, and reverse the recent regression of the dominant species (Quercus ilex) induced by climate change. Thinning increased aboveground productivity and reduced stem mortality in this Mediterranean forest during four years just after thinning, contributing to the maintenance of forest functioning under changing climatic conditions. Q. ilex was the only species positively affected by the thinning: stem growth increased for all stem sizes, and mortality was significantly lower in thinned plots. On the contrary, mortality rates of Phillyrea latifolia and Arbutus unedo were not significantly lower. Stem growth increased for P. latifolia only in the smallest stem-size class. Our results highlight the suitability of selective thinning for improving the forest productivity and ensuring the conservation of Mediterranean coppices. Other benefits of selective thinning, such as a decrease in the risk of fire dispersion and an increase in the water supply for human populations, are also discussed.

Microalgal lipid recovery for biodiesel production is currently considered suboptimal, but pre-treatment of algal biomass, the use of solvent mixtures and the positioning of transesterification can lead to increased yields. Here, the effect of various reportedly successful pre-treatments and solvent mixtures were directly compared to each other and combined with direct and indirect transesterification methods using the oleaginous microalga Tetraselmis sp. M8. Microwave and thermal pre-treatments were applied and the total lipid and fatty acid methyl ester (FAME) recoveries were investigated. The application of pre-treatments increased FAME recovery through indirect transesterification when a Soxhlet system was used but they had no significant effect for direct transesterification. Gravimetric analyses of total lipids revealed that lipid recovery was highest when utilizing the chloroform-based Bligh and Dyer extraction method; however FAME yield was the highest when applying a Soxhlet system utilizing a solvent mixture of hexane-ethanol (3:1). Total lipid recovery did not necessarily correlate with the recovery of FAMEs. The highest FAME recovery was achieved from thermal or microwave pre-treated biomass followed by indirect transesterification through Soxhlet extraction. FAME recovery could be more than doubled (increase of up to 171%) under these conditions. We conclude that a simple thermal pre-treatment (80°C for 10 min) in combination with solvent mixture extraction through indirect transesterification may present a cost-effective and scalable option for large-scale lipid extraction from microalgae.

The Nigerian government is committed to sustaining rice production to meet national demand. Nevertheless, political tension and climate-induced stressors remain crucial constraints in achieving policy targets. This study examines whether climate change and political instability significantly threaten rice production in Nigeria. First, we employed nonparametric methods to estimate the country's rainfall and temperature trends between 1980Q1 and 2015Q4. Second, we employed the autoregressive distributed lag (ARDL) technique to examine the effects of climate change and political instability on rice production. The results show that while temperature has an increasing pattern, rainfall exhibits no significant trend. The findings from the ARDL estimate reveal that rice production responds negatively to temperature changes but is less sensitive to changes in rainfall. In addition, political instability adversely affects rice production in Nigeria. We argue that Nigeria's slow growth in rice production can be traced back to the impact of climate change and political tension in rice farming areas. As a result, reducing the overall degree of conflict to ensure political stability is critical to boosting the country's self-sufficiency in rice production. We also recommend that farmers be supported and trained to adopt improved rice varieties less prone to extreme climate events while supporting them with irrigation facilities to facilitate rice production.

Abstract Integration of solar photovoltaic (PV) and battery storage systems is an upward trend for residential sector to achieve major targets like minimizing the electricity bill, grid dependency, emission and so forth. In recent years, there has been a rapid deployment of PV and battery installation in residential sector. In this regard, optimal planning of PV-battery systems is a critical issue for the designers, consumers, and network operators due to high number of parameters that can affect the optimization problem. This paper aims to present a comprehensive and critical review on the effective parameters in optimal planning process of solar PV and battery storage system for grid-connected residential sector. The key parameters in process of optimal planning for PV-battery system are recognized and explained. These parameters are economic and technical data, objective functions, energy management systems, design constraints, optimization algorithms, and electricity pricing programs. A timely review on the state-of-the-art studies in PV-battery optimal planning is presented. The challenges, trends and latest developments in the topic are discussed. At the end, scopes for future studies are developed. It is found that new guidelines should be provided for the customers based on various electricity rates and demand response programs. Also, several design considerations like grid dependency and resiliency need further investigation in the optimal planning of PV-battery systems.

La production industrielle d'huile de palme génère simultanément une quantité substantielle de fibres de grappe de fruits vides (EFB) qui pourraient être utilisées comme matière première dans une bioraffinerie à base de lignocellulose. Les sous-produits de la lignine générés par ce processus peuvent offrir des possibilités d'isolation des produits à valeur ajoutée, tels que le p-hydroxybenzoate (pBz), pour aider à compenser les coûts d'exploitation. L'analyse de la lignine EFB par spectroscopie de résonance magnétique nucléaire (RMN) a clairement révélé la présence d'acétate lié et de pBz, la saponification révélant que 1,1 % en poids de l'EFB était du pBz ; avec une teneur en lignine de 22,7 %, 4,8 % de la lignine est du pBz qui peut être obtenu comme composant pur pour être utilisé comme charge chimique. L'analyse de la lignine EFB par RMN et dérivatisation suivie d'un clivage réducteur (DFRC) a montré que le pBz acylate sélectivement le groupe γ-hydroxyle des unités S. Cette sélectivité suggère que le pBz, de manière analogue à l'acétate dans le kénaf, le p-coumarate dans les graminées et le ferrate dans un peuplier transgénique augmenté d'une féruloyl-CoA monolignol transférase (FMT), est incorporé dans la chaîne de lignine en croissance via son conjugué monolignol γ-p-hydroxybenzoylé. L'implication de tels conjugués dans la lignification des palmiers est prouvée par l'observation de nouvelles unités couplées au β-β non résinol p-hydroxybenzoylé dans les lignines. Ensemble, les données impliquent l'existence de p-hydroxybenzoyl-CoA :monolignol transférases qui sont impliquées dans la lignification chez les différents saules (Salix spp.), peupliers et peupliers faux-trembles (Populus spp., famille des Salicacées) et palmiers (famille des Arecacées) qui ont des lignines p-hydroxybenzoylées. Même sans augmenter les niveaux par la sélection ou le génie génétique, les « déchets » actuels de l'EFB d'huile de palme devraient être en mesure de générer un flux important d'acide p-hydroxybenzoïque qui offre des opportunités pour le développement de produits à valeur ajoutée dérivés de l'industrie du palmier à huile. La producción industrial de aceite de palma genera simultáneamente una cantidad sustancial de fibras de racimo de frutas vacías (EFB) que podrían utilizarse como materia prima en una biorrefinería a base de lignocelulosa. Los subproductos de lignina generados por este proceso pueden ofrecer oportunidades para el aislamiento de productos de valor agregado, como el p-hidroxibenzoato (pBz), para ayudar a compensar los costos operativos. El análisis de la lignina EFB por espectroscopía de resonancia magnética nuclear (RMN) reveló claramente la presencia de acetato unido y pBz, y la saponificación reveló que el 1,1% en peso del EFB era pBz; con un contenido de lignina del 22,7 %, el 4,8 % de la lignina es pBz que se puede obtener como un componente puro para su uso como materia prima química. El análisis de la lignina EFB por RMN y la derivatización seguida de escisión reductora (DFRC) mostró que pBz acila selectivamente el grupo γ-hidroxilo de las unidades S. Esta selectividad sugiere que pBz, análogamente con acetato en kenaf, p-cumarato en gramíneas y ferular en un álamo transgénico aumentado con una feruloil-CoA monolignol transferasa (FMT), se incorpora a la cadena de lignina en crecimiento a través de su conjugado de monolignol γ-p-hidroxibenzoilado. La participación de dichos conjugados en la lignificación de la palma se demuestra al observar nuevas unidades no acopladas a β-β-resinol p-hidroxibenzoiladas en las ligninas. Juntos, los datos implican la existencia de p-hidroxibenzoil-CoA:monolignol transferasas que participan en la lignificación en los diversos sauces (Salix spp.), álamos y álamo temblón (Populus spp., familia Salicaceae) y palmeras (familia Arecaceae) que tienen ligninas p-hidroxibenzoiladas. Incluso sin mejorar los niveles mediante mejoramiento o ingeniería genética, los 'desechos' actuales de aceite de palma EFB deberían ser capaces de generar una corriente considerable de ácido p-hidroxibenzoico que ofrezca oportunidades para el desarrollo de productos de valor agregado derivados de la industria de la palma aceitera. The industrial production of palm oil concurrently generates a substantial amount of empty fruit bunch (EFB) fibers that could be used as a feedstock in a lignocellulose-based biorefinery. Lignin byproducts generated by this process may offer opportunities for the isolation of value-added products, such as p-hydroxybenzoate (pBz), to help offset operating costs. Analysis of the EFB lignin by nuclear magnetic resonance (NMR) spectroscopy clearly revealed the presence of bound acetate and pBz, with saponification revealing that 1.1 wt% of the EFB was pBz; with a lignin content of 22.7 %, 4.8 % of the lignin is pBz that can be obtained as a pure component for use as a chemical feedstock. Analysis of EFB lignin by NMR and derivatization followed by reductive cleavage (DFRC) showed that pBz selectively acylates the γ-hydroxyl group of S units. This selectivity suggests that pBz, analogously with acetate in kenaf, p-coumarate in grasses, and ferulate in a transgenic poplar augmented with a feruloyl-CoA monolignol transferase (FMT), is incorporated into the growing lignin chain via its γ-p-hydroxybenzoylated monolignol conjugate. Involvement of such conjugates in palm lignification is proven by the observation of novel p-hydroxybenzoylated non-resinol β–β-coupled units in the lignins. Together, the data implicate the existence of p-hydroxybenzoyl-CoA:monolignol transferases that are involved in lignification in the various willows (Salix spp.), poplars and aspen (Populus spp., family Salicaceae), and palms (family Arecaceae) that have p-hydroxybenzoylated lignins. Even without enhancing the levels by breeding or genetic engineering, current palm oil EFB 'wastes' should be able to generate a sizeable stream of p-hydroxybenzoic acid that offers opportunities for the development of value-added products derived from the oil palm industry. ينتج الإنتاج الصناعي لزيت النخيل في الوقت نفسه كمية كبيرة من ألياف مجموعة الفاكهة الفارغة (EFB) التي يمكن استخدامها كمادة وسيطة في مصفاة حيوية تعتمد على اللجينوسليلوز. قد توفر المنتجات الثانوية لليجنين الناتجة عن هذه العملية فرصًا لعزل المنتجات ذات القيمة المضافة، مثل p - hydroxybenzoate (pBz)، للمساعدة في تعويض تكاليف التشغيل. كشف تحليل اللجنين EFB بواسطة مطياف الرنين المغناطيسي النووي (NMR) بوضوح عن وجود أسيتات مرتبطة و pBz، مع كشف التصبن أن 1.1 ٪ بالوزن من EFB كان pBz ؛ مع محتوى اللجنين بنسبة 22.7 ٪، 4.8 ٪ من اللجنين عبارة عن pBz يمكن الحصول عليه كمكون نقي للاستخدام كمادة وسيطة كيميائية. أظهر تحليل اللجنين EFB بواسطة NMR والاشتقاق متبوعًا بالانقسام الاختزالي (DFRC) أن pBz يعمل بشكل انتقائي على أسيتيل مجموعة γ - hydroxyl من وحدات S. تشير هذه الانتقائية إلى أن pBz، بالتناظر مع الأسيتات في الكناف، و p - comarate في الأعشاب، و ferulate في حور معدّل وراثيًا معززًا بـ feruloyl - CoA monolignol transferase (FMT)، يتم دمجه في سلسلة اللجنين المتنامية عبر γ - p - hydroxybenzoylated monolignol conjugate. ثبت تورط مثل هذه المترافقات في ترصيع النخيل من خلال ملاحظة وحدات p - hydroxybenzoylated غير الراتينول β - β المقترنة في اللجنين. معا، تشير البيانات إلى وجود p - hydroxybenzoyl - CoA: monolignol transferases التي تشارك في تبييض في الصفصاف المختلفة (Salix spp.)، الحور والحور (Populus spp.، عائلة Salicaceae)، والنخيل (عائلة Arecaceae) التي تحتوي على p - hydroxybenzoylated lignins. حتى من دون تعزيز المستويات عن طريق التكاثر أو الهندسة الوراثية، يجب أن تكون "نفايات" زيت النخيل الحالية قادرة على توليد تيار كبير من حمض p - hydroxybenzoic الذي يوفر فرصًا لتطوير منتجات ذات قيمة مضافة مشتقة من صناعة نخيل الزيت.