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The article investigates the feasibility of district heating in a small town adjacent to a Kraft pulp mill in eastern Canada. A detailed heat demand analysis is performed for all buildings using a geographical information system and archived data provided by the municipality. The study shows that the entire space heating requirement of the town can be supplied by steam from the mill, even during exceptional peak demands. A screening test based on load density indicators, however reveals that a district heating serving the entire town would probably not be economically viable. An economic analysis of partial districts show that a district covering about half of the town can be economically viable with a proper balance between the price of the steam sold by the mill to the district opera- tor and the cost of the energy sold to customers. [ABSTRACT FROM AUTHOR]

Due to the increased use of variable renewable energy sources, more capacity for reserves is required. Non-generating resources such as large industrial consumers can arbitrage energy prices and provide reserve capacity by exploiting the inherent flexibility in selected industrial processes. A large enough industrial consumer can capitalize on this flexibility through optimized bidding in electricity markets. In this work, the day-ahead cost minimization of a risk-averse pulp and paper mill is formulated as a two-stage stochastic problem, considering thermodynamic and electrical constraints. The bids in the energy and reserve markets are jointly optimized subject to price uncertainty as well as uncertainty of frequency realization. The results of a case study in Sweden display a significant economic benefit in exploiting the flexibility of integrated pulp and paper mills with electric boilers. The expected cost of the pulp and paper mill resulting from different strategies are compared and the risk-aversion of the pulp and paper mill is investigated. Reserve offers are mainly facilitated by fast-acting electric boilers and supported by flexibility in the steam network. We show that reserve offers can significantly improve the profitability of the pulp and paper mill. • Pulp and paper mills with electric boilers can supply primary frequency reserves. • Electric boilers can provide up to 50 MW flexibility of 100 MW rating. • An algorithm is developed to optimize the energy & reserve bids of the mill. • Expected cost savings range between 7.4% in summer and 2.3% in winter. [ABSTRACT FROM AUTHOR]

Abstract Background Pulp refining is an energy consuming, but integral part of paper production with the aim to increase tensile strength and smoothness of paper sheets. Commercial enzyme formulations are used to lower the energy requirements by pre-treatment of pulp before refining. However, a high number of different commercial enzyme products are available on the market containing enzymes of varying origin and composition, which complicates the prediction of their behavior, especially using different pulp types. Results Endoglucanase-rich enzyme formulations were characterized regarding enzyme activity at different temperatures, resulting in a significant decrease of activity above 70 °C. Some enzyme preparations additionally contained arabinosidase, xylanase and β-glucosidase activity consequently resulting in a release of xylose and glucose from pulp as determined by high-performance liquid chromatography. Interestingly, one enzyme formulation even showed lytic polysaccharide monooxygenase (LPMO) activity of 3.05 nkat mg−1. A correlation between enzyme activity using the endoglucanase specific derivatized cellopentaose (CellG5) substrate and enzyme performance in laboratory PFI (Papirindustriens forskningsinstitut) refining trials was observed on softwood pulp resulting in a maximum increase in the degree of refining values from 27.7°SR to 32.7°SR. When added to a purified endoglucanase enzyme (31.6°SR), synergistic effects were found for cellobiohydrolase II (34.7°SR) or β-glucosidase enzymes (35.7°SR) in laboratory refining. Comparison with previously obtained laboratory refining results on hardwood pulp allowed differences in enzyme performance based on varying pulp types to be elucidated. Conclusions Interestingly, the individual enzymes indeed showed different refining effects on softwood and hardwood pulp. This difference could be predicted after development of an adapted enzyme activity assay by combination of the derivatized cellopentaose CellG5 substrate with either softwood or hardwood sulfate pulp.

Waste paper as a kind of biomass contains a great quantity of cellulose which is a renewable energy resource. However, complex cellulose supramolecular structure restricts the conversion of waste paper in near-critical water. This study aimed to investigate the change characteristics of cellulose supramolecular structure (hydrogen bond models and crystallinity) during hydrolysis and its effects on 5-HMF yield. Waste paper has been treated in near-critical water at 375 °C and 22.5 MPa for a reaction time (160–240 s) and correlation between 5-HMF yield and the supramolecular structure of cellulose residues has been built up. The 5-HMF yield was increased with the increase of intermolecular hydrogen bonds content in cellulose residues and was increased first and then decreased with the increase of crystallinity of cellulose residues. The rate of decrystallization was out of sync with that of depolymerization, which also influenced 5-HMF yield. Reaction time can be a macro method to adjust the supramolecular structure of cellulose during the conversion of waste paper to obtain more 5-HMF. It showed that 5-HMF yield reached maximum 9.41% ± 0.47% when the intermolecular hydrogen bonds content of cellulose in residue was 67.77% and the crystallinity of cellulose in residue was 57.14% at 200 s. [ABSTRACT FROM AUTHOR]

The development of renewable energy sources minimizes the burning of fossil fuels for clean and green environment. Electrochemical energy storage/conversion device pays a way towards sustainable development that concludes an emerging field in the trends of the research community. Prominently, the functional materials with suitable structure and property determine the performance and durability of the devices. In recent times, graphene with its tremendous properties play a major role in electrochemical energy device applications. Meanwhile, the graphene-based electrodes were fabricated by various coating techniques on existing electrodes that utilized for energy device fabrication. Apart from these, it is also fabricated in a paper like a form (self-supported or free-standing) with its remarkable high conductivity, flexibility, robustness and electrochemical behavior which have been nominated for fabrication of flexible energy devices. Paper-like electrodes become an emerging field to fabricate a light-weight and flexible electronic devices for future prospects. Thus, we have summarized a synthetic strategy of graphene paper and its properties that potentially focused on flexible device fabrication in both the energy storage and conversion system. Hence, this review boosts up the forthcoming researchers to enhance the device performance with interrelating free-standing graphene and other host material. Number of publications from 2009 to 2018 based on free-standing graphene-paper in energy device applications gathered from Web of Science database search engine. Image 10612 [ABSTRACT FROM AUTHOR]

Copyright of Universitas Scientiarum is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pulp and paper industry is one of the most polluting, energy and water intensive industries in the world. Produced pulp and paper mill sludge (PPMS) faces a major problem for handling and its management. An anaerobic digestion has become an alternative source. This review provides a detailed summary of anaerobic digestion of PPMS – An overview of the developments and improvement opportunities. This paper explores the different pretreatment methods to enhance biogas production from the PPMS. First, the paper gives an overview of PPMS production, and then it reviews PPMS as a substrate for anaerobic digestion with or without pretreatment. Finally, it discuss the optimal condition and concentration of organic and inorganic compounds required for the anaerobic metabolic activity. Future research should focus on the combination of different pretreatment technologies, relationship between sludge composition, reactor design and its operation, and microbial community dynamics. [ABSTRACT FROM AUTHOR]

This paper addresses the assessment of woody biomass resources in Russia and the Baikal region. The analysis of the literature demonstrates that the Baikal region has considerable amounts of waste from the logging, timber processing, and pulp and paper industries (up to 220 PJ). A review of utilization technologies for woody biomass demonstrates that the existing technologies based on biomass gasification are promising for energy purposes. The gasification of biomass for small-capacity power plants has some advantages compared to its combustion. This paper considers an autonomous power system that consists of photovoltaic converters, wind turbines, storage batteries, a biomass gasification power plant, and a diesel power plant. A mathematical model used to optimize the system's structure finds the minimum of the total discounted costs for the creation and operation of the system with some constraints met. Based on mathematical modeling, the cost-effectiveness of such a power supply system is assessed for different climatic zones of the Baikal region and the coastal area of Lake Baikal. The findings indicate that the optimal solution is the integration of various renewable energy sources in hybrid power systems. The proportion of energy sources of different types in the installed capacities is found. The study demonstrates that the optimal structure of the power system can provide significant savings (the total discounted costs are reduced by almost 2.5 times compared to the option using a diesel power plant alone). [ABSTRACT FROM AUTHOR]

In recent years, the domain of renewable energy communities has experienced dynamic growth, spurred by European Union (EU) legislation that became law for all 27 Member States in June 2021. This legislative framework intensified research efforts aimed at discovering new methods for sustainable energy sources through the development of individual and collective energy communities. Each EU country has implemented distinct frameworks for renewable energy communities, leading to varied legislative approaches. This has spurred exponential investment, facilitating the deployment of photovoltaic and battery energy storage systems, offering significant economic and environmental benefits to community members. Against this backdrop, the purpose of this analysis is to investigate academic publications related to renewable energy communities. Using a dataset extracted from the ISI Web of Science database, this study employs a bibliometric approach to identify the main authors, affiliations, and journals and analyze collaboration networks, as well as discern key topics and the countries involved. The analysis reveals an annual growth rate of 42.82%. Through thematic maps, WordClouds, three-field plots, and a review of the top 10 globally cited documents, this study provides a comprehensive perspective on the evolving domain of renewable energy communities. [ABSTRACT FROM AUTHOR]

The distribution grid experiences node voltage fluctuations due to the growing uncertainty of large-scale renewable energy sources A practical solution is establishing a chance-constrained optimal model to deal with the uncertainties. However, using this method needs to know the accurate probability distribution of node power injections, which has limitations in application. Therefore, this paper proposes a distributionally robust chanceconstrained optimization method for power grid operation based on the ambiguity set of probability distributions. Firstly, considering voltage security constraints, this paper establishes a chance-constrained model to minimize the cost of active power regulation. Besides, based on the Wasserstein ambiguity set, a linearized method is proposed to convexify the objective function. Moreover, the conditional risk value (CVaR) is applied to convert the uncertain model into a deterministic model. The effectiveness of the proposed method is validated through optimization results obtained for the modified PG&E69-bus distribution grid. [ABSTRACT FROM AUTHOR]

The accuracy of short‐term photovoltaic (PV) power prediction is crucial for maintaining power system stability and grid scheduling. Here, a short‐term PV power prediction framework is proposed considering combined weather similarity day screening, signal decomposition noise reduction and hybrid deep learning to realize PV power prediction. First, a combined meteorological similar day screening model is constructed to screen out historical days similar to the day, which reduces the number of training sets; Second, Synchrosqueezing Wavelet Transform is utilized to eliminate data noise. Third, a Convolution Neural Network‐Gate Recurrent Unit (CNN‐GRU) network is constructed to extract periodic and nonlinear features in the PV power generation data series and to capture the relationship features between PV power generation and meteorological factors to improve the prediction accuracy. Fourth, the Sparrow Search Algorithm is introduced to perform hyper‐parameter optimization of the CNN‐GRU network to accelerate the model convergence and improve the model training efficiency. Finally, this paper conducts simulation experiments and the experimental results show that the prediction method proposed in this paper can effectively improve the prediction accuracy of short‐term PV power compared to the baseline model, and the method proposed in this paper is superior to other conventional methods. [ABSTRACT FROM AUTHOR]

This document is a guest editorial from the journal IET Generation, Transmission & Distribution. It discusses the use of artificial intelligence (AI) in reliable forecasting for energy sectors. The editorial highlights the challenges of integrating renewable energy sources and fluctuating electricity demand, and emphasizes the importance of accurate forecasting for system operators. The document also provides summaries of several papers included in a special issue on AI-empowered forecasting in energy sectors, covering topics such as load forecasting, wind power prediction, and control parameter optimization. The editorial concludes by recommending further research and practical implementations of AI approaches in the energy sectors. [Extracted from the article]

One-third of all greenhouse gas emissions come from the world's building stock while accounting for 40% of global energy use. There is no way to combat global warming or attain energy independence without addressing the inefficiency of the building sector. This sector is the second consumer of electricity after the industrial sector in Morocco and is ranked third emitter after the energy sector and transportation sector. Using Ifrane as a case study, this paper examines and reviews the city's energy use and the initiatives taken to improve building efficiency. The findings showed that, during the analyzed period, i.e., from 2014 to 2022, Ifrane's annual electricity consumption climbed steadily from 35 to 43 GWh. The government of Morocco has implemented effective laws, guidelines and regulations, as well as publicized ways to reduce energy consumption and increase energy efficiency. However, gathered data and survey results revealed opportunities and challenges for enhancing Ifrane's efficient energy use. The study also evaluates government programs, codes/standards and related actions for the improvement of household energy efficiency. As part of the review, the available literature was analyzed to assess the effectiveness of energy behavior and awareness, the impact of an economical and sustainable building envelope, the impact of building retrofitting programs, the importance of energy-performing devices and appliances, the adoption of smart home energy management systems, the integration of renewable energies for on-site clean energy generation and the role of policies and governance in the building sector in Ifrane. A benchmark evaluation and potential ideas are offered to guide energy policies and improve energy efficiency in Ifrane and other cities within the same climate zone.

Power grids in the 21st century face unprecedented challenges, including the urgent need to combat pollution, mitigate climate change, manage dwindling fossil fuel reserves, integrate renewable energy sources, and meet greater energy demand due to higher living standards. These challenges create heightened uncertainty, driven by the intermittent nature of renewables and surges in energy consumption, necessitating adaptable demand response (DR) strategies. This study addresses this urgent situation based on a statistical analysis of recent scientific research papers. It evaluates the current trends and DR practices in buildings, recognizing their pivotal role in achieving energy supply–demand equilibrium. The study analysis provides insight into building types, sample sizes, DR modeling approaches, and management strategies. The paper reveals specific research gaps, particularly the need for more detailed investigations encompassing building types and leveraging larger datasets. It underscores the potential benefits of adopting a multifaceted approach by combining multiple DR management strategies to optimize demand-side management. The findings presented in this paper can provide information to and guide future studies, policymaking, and decision-making processes to assess the practical potential of demand response in buildings and ultimately contribute to more resilient and sustainable energy systems. [ABSTRACT FROM AUTHOR]

Although a significant amount of brewery wastewater (BW) is generated during beer production, the nutrients in the BW could be reused as a potential bio-resource for biohydrogen production. Therefore, improvements in photofermentative biohydrogen production due to a combination of BW and pulp and paper mill effluent (PPME) as a mixed production medium were investigated comprehensively in this study. The experimental results showed that both the biohydrogen yield and the chemical oxygen demand removal were improved through the combination of BW and PPME. The best biohydrogen yield of 0.69 mol H/L medium was obtained using the combination of 10 % BW + 90 % PPME (10B90P), while the reuse of the wastewater alone (100 % BW and 100 % PPME) resulted in 42.3 and 44.0 % less biohydrogen yields than the highest yield, respectively. The greatest light efficiency was 1.97 % and was also achieved using the combination of both wastewaters at 10B90P. This study revealed the potential of reusing and combining two different effluents together, in which the combination of BW and PPME improved the nutrients and light penetration into the mixed production medium. [ABSTRACT FROM AUTHOR]

An enormous gap exists between Africa's current electrification rate and the 2030 UN goal to ensure universal access to modern energy. A study by Sanoh et al. published in Renewable Energy in 2014 [1] is a rare example of finding a cost minimal solution for the Africa-wide generation and transmission network. Unfortunately, however, the paper exhibits a number of relatively serious flaws that demand attention given the alarming paucity of such research on Africa. Five issues of the study by Sanoh et al. are identified and discussed in this commentary paper. Specifically, the study does not account for capacity factors when deriving required capacity additions, misses transmission losses when sizing generation capacity, models country-level import constraints incorrectly, introduces a supply option redundancy, and reports optimisation results that can be shown to be mathematically sub-optimal. As a result of some of these issues, the Sanoh et al. significantly underreport the required capacity to meet additional African demand in 2025. In addition to discussing these flaws, this paper provides potential approaches to avoid each of the five issues. [ABSTRACT FROM AUTHOR]

This article discusses the role of power electronic converters in smart grids and electric vehicle applications. The authors highlight the technical connection between renewable energy, smart grids, energy storage, and electric vehicles. The special issue includes twelve accepted papers that cover topics such as high gain DC-DC converters, power converters for electric vehicle and motor drive applications, and power system applications. The papers present various novel topologies and control techniques, indicating the rapid growth and future potential of power converters in these fields. The authors express their appreciation to the contributing authors and anonymous reviewers for their valuable contributions to this special issue. [Extracted from the article]

Renewable energy resources can potentially solve global warming issues that arise from the large amounts of CO2 emissions from currently used energy resources. Microbial fuel cells (MFC) can produce electrical energy from the environment, making them attractive for energy harvesting. The structures and mechanisms of MFC have been studied for a few decades, and the performance of MFC has constantly been improved using new materials in the devices or by interacting microbial species on the anode chamber of MFC. However, the ecological phenomena, especially inter‐species interactions, within the microbial community in MFC are still largely unknown. Analysis and control of the microbial community have high potential to improve the MFC performance. In this idea paper, I have provided ways to analyze the species interactions in the microbial communities of MFC: (a) empirical dynamic modeling for detecting species interactions in MFC, and (b) network analysis to explore the core microbe species in the MFC. The interaction analyses of the microbial communities in MFC devices can potentially contribute to improving the performance of MFC. [ABSTRACT FROM AUTHOR]

The rapid growth of environment pressures and fast depletion of fossil fuels compel public to pay more attention on developing affordable and efficient catalysts for renewable energy production. Metal (Co, Fe, Ni, etc.) phosphide nanoparticles uniformly encapsulated in porous N,P-codoped nanofibrous carbon coated on carbon paper (MeP@NPC/CP) are prepared through one-pot carbonization-phosphorization strategy, which are potential for effective electrocatalytic water reduction/oxidation reactions. The well-designed self-supported structure and the abundant accessible active centers together contribute to the high electrocatalytic performance for hydrogen and oxygen evolution. Remarkably, an alkaline electrolyzer assembled from CoP@NPC/CP as cathode and anode can afford the current density of 10 mA cm −2 at the voltage of 1.67 V for overall water splitting in alkaline media with excellent stability. The easily prepared route with suitable structural and textural properties endows this self-supported materials with versatile function as abundant metal catalysts for realistic energy conversion and storage systems. [ABSTRACT FROM AUTHOR]

Large-scale growth of low-cost, efficient, and durable non-noble metal-based electrocatalysts for water splitting is crucial for future renewable energy systems. Atomic layer deposition (ALD) provides a promising route for depositing uniform thin coatings of electrocatalysts, which are useful in many technologies, including the splitting of water. In this communication, we report the growth of a NiO/Ni catalyst directly on carbon fiber paper by atomic layer deposition and report subsequent reduction and oxidation annealing treatments. The 10-20 nm NiO/Ni nanoparticle catalysts can reach a current density of 10 mA·cm-2 at an overpotential of 189 mV for hydrogen evolution reactions and 257 mV for oxygen evolution reactions with high stability. We further successfully achieved a water splitting current density of 10 mA·cm-2 at 1.78 V using a typical NiO/Ni coated carbon fiber paper two-electrode setup. The results suggest that nanoparticulate NiO/Ni is an active, stable, and noble-metal-free electrocatalyst, which facilitates a method for future water splitting applications. [ABSTRACT FROM AUTHOR]

This work reports an innovative simulation method for effectively utilizing paper-mill sludge based on the co-gasification approach for energy-enriched renewable fuel production. An Aspen plus-based co-gasification model was developed to simulate and examine the synergetic effects of biomass and paper-mill sludge co-gasification. Initially, the model was validated using experimental data from the reported literature and found good agreement regarding gasification and co-gasification approaches. Sensitivity analysis of biomass gasification revealed that the maximum H 2 content of 29.6% and CO (36.0%), LHV (7.8 MJ/Nm3), 72.2% (CCE) was obtained at optimal (850 °C: temperature; 1 bar: pressure; 0.2: ER) conditions. Further, the H 2 proportion enhanced, and CO declined to 38.8 and 30.7% at the same operating conditions, respectively, with a co-gasification ratio of 50% compared to 0% (H 2 : 29.6% and CO: 36.0%). However, with increasing the co-gasification ratio beyond 20%, the CO content started to follow upward trends; at the same CGR, the H 2 , LHV, and CCE observed were 36.0%, 7.76 MJ/Nm3, and 65.2%, respectively. Hence, the developed co-gasification model can provide vital information for large-scale gasifier design, operating decisions, and optimization using different biomass blends. • Biomass and PMS utilization to produce renewable fuel. • Co-gasification parametric effects evaluation on product yield. • Increasing the proportion of PMS in feedstock mixture increases H 2 content. • 20% PMS co-gasification provided consistency with reported literature. [ABSTRACT FROM AUTHOR]

Copyright of Hacettepe University Journal of Economics & Administrative Sciences / Hacettepe Üniversitesi Iktisadi ve Idari Bilimler Fakültesi Dergisi is the property of Hacettepe University, Faculty of Economic & Administrative Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The demand for more environmentally friendly alternative renewable fuels is growing as fossil fuel resources are depleting significantly. Consequently, bioethanol has attracted interest as a potentially viable fuel. The key steps in second-generation bioethanol production include pretreatment, saccharification, and fermentation. The present study employed simultaneous saccharification and fermentation (SSF) of cellulose through bacterial pathways to generate second-generation bioethanol utilizing corncobs and paper waste as lignocellulosic biomass. Mechanical and chemical pretreatments were applied to both biomasses. Then, two bacterial strains, Bacillus sp. and Norcadiopsis sp., hydrolysed the pretreated biomass and fermented it along with Achromobacter sp., which was isolated and characterized from a previous study. Bioethanol production followed by 72 h of biomass hydrolysis employing Bacillus sp. and Norcadiopsis sp., and then 72 h of fermentation using Achromobacter sp. Using solid phase micro extraction combined with GCMS the ethanol content was quantified. SSF of alkaline pretreated paper waste hydrolysed by Bacillus sp. following the fermentation by Achromobacter sp. showed the maximum ethanol percentage of 0.734±0.154. Alkaline pretreated corncobs hydrolyzed by Norcadiopsis sp. yielded the lowest ethanol percentage of 0.155±0.154. The results of the study revealed that paper waste is the preferred feedstock for generating second-generation bioethanol. To study the possible use of ethanol-diesel blends as an alternative biofuel E2, E5, E7, and E10 blend emulsions were prepared mixing commercially available diesel with ethanol. The evaluated physico-chemical characteristics of the ethanol-diesel emulsions fulfilled the Ceypetco requirements except for the flashpoint revealing that the lower ethanol-diesel blends are a promising alternative to transport fuels. As a result, the current study suggests that second generation bioethanol could be used as a renewable energy source to help alleviate the energy crisis..

This paper investigates the impact of combining CO2 capture and storage with alternative systems for biomass-based combined heat and power production (CHP) in Kraft pulp and paper mills. We compare heat, power, and CO2 balances of systems with alternative configurations of the CHP and CO2-capture systems. Because the captured CO2 comes from renewable biomass, the studied systems yield negative CO2 emissions. It is shown that pulp mills and integrated pulp and paper mills have the potential to become net exporters of biomass-based electricity while at the same time removing CO2 from the atmosphere on a net basis. The study shows that that the overall best CO2 abatement is achieved when CO2 capture is carried out within a biomass integrated gasifier with combined cycle where the syngas undergoes a CO-shift reaction. This configuration combines efficient energy conversion with a high CO2 capture efficiency. Furthermore, cost curves are constructed, which show how the cost of CO2 capture and storage in pulp and paper mills depends on system configuration and the CO2 transportation distance. [Copyright &y& Elsevier]

Lignocellulosic biomass (LB) is widely used in the field of renewable energy production because of its low price and easy availability. Many kinds of fuels from LB have been developed and are being used in our daily lives. The LB energy has become an indispensable part in the energy mix on account of its steady and sustainable supply. However, there are some neglected issues and misconceptions regarding its development and utilization, although it has numerous advantages over other energy sources. Firstly, its development and utilization can change the living environment of organisms and decrease biodiversity to some extent, relative to using other sources of energy. Secondly, it is not a completely carbon-neutralized fuel as has been claimed in some literature. Finally, its excessive exploitation can seriously damage the environment and biosystems. This editorial will give a brief discussion on some neglected issues and misconceptions during its development and utilization for its suitable exploitation. [ABSTRACT FROM AUTHOR]

Discusses the challenges facing the European paper industry and managing director Teresa Presas of the Confederation of European Paper Industries (CEPI). Reorganization of the CEPI to accommodate expansion of the European Union; Chemical legislation; Recycling targets; Future wood availability; Sustainability; Renewable energy sources; Emission trading directive.