Effects of habitat factors on the plant diversity on naturally-restored wind farm slopes.

This study investigated naturally-restored plant communities on wind farm slopes and analyzed the effects of various habitat factors on the plant diversity. The findings provide a technical support for the ecological restoration of mountainous slopes.Twenty-one slopes on five wind farms were selected and the characteristics of the habitat, including slope position, slope aspect, slope gradient, altitude, years since restoration, and plant communities, were recorded. The species richness of the plant communities and the vegetation diversity indexes of these wind farms were measured and calculated, including the Shannon-Wiener diversity index (H'), Pielou's species evenness index (J), and Margalef's richness index (R). The key factors influencing plant diversity were identified using a stepwise regression analysis. A total of 36 families, 54 genera, and 57 species of plants were identified in this study with the Gramineae, Compositae, Rosaceae, Liliaceae, and Juglandaceae families the mostly predominant. Cynodon dactylon, Rubus lambertianus Ser., and Lindera glauca were the dominant species of herbs, shrubs, and trees, respectively. The highest number of species were found on lower slopes, slopes with semi-sunny aspects, slopes with gradients 30-50°, elevation below 500 m, and on slopes with at least five years since restoration. The plant diversity H' and R tended to be higher on lower slopes than on upper slopes, and higher on slopes with semi-shady aspects than on slopes with semi-sunny aspects (P < 0.05). Vegetation diversity increased with the years since restoration. Slope position and slope aspect were identified as the primary influencing factors, and the H' and R indexes were major indicators of changes in plant diversity on mountainous slopes.

Bioengineering of biowaste to recover bioproducts and bioenergy: A circular economy approach towards sustainable zero-waste environment.

The inevitable need for waste valorisation and management has revolutionized the way in which the waste is visualised as a potential biorefinery for various product development rather than offensive trash. Biowaste has emerged as a potential feedstock to produce several value-added products. Bioenergy generation is one of the potential applications originating from the valorisation of biowaste. Bioenergy production requires analysis and optimization of various parameters such as biowaste composition and conversion potential to develop innovative and sustainable technologies for most effective utilization of biowaste with enhanced bioenergy production. In this context, feedstocks, such as food, agriculture, beverage, and municipal solid waste act as promising resources to produce renewable energy. Similarly, the concept of microbial fuel cells employing biowaste has clearly gained research focus in the past few decades. Despite of these potential benefits, the area of bioenergy generation still is in infancy and requires more interdisciplinary research to be sustainable alternatives. This review is aimed at analysing the bioconversion potential of biowaste to renewable energy. The possibility of valorising underutilized biowaste substrates is elaborately presented. In addition, the application and efficiency of microbial fuel cells in utilizing biowaste are described in detail taking into consideration of its great scope. Furthermore, the review addresses the significance bioreactor development for energy production along with major challenges and future prospects in bioenergy production. Based on this review it can be concluded that bioenergy production utilizing biowaste can clearly open new avenues in the field of waste valorisation and energy research. Systematic and strategic developments considering the techno economic feasibilities of this excellent energy generation process will make them a true sustainable alternative for conventional energy sources.

Spatial integration framework of solar, wind, and hydropower energy potential in Southeast Asia.

Amid its massive increase in energy demand, Southeast Asia has pledged to increase its use of renewable energy by up to 23% by 2025. Geospatial technology approaches that integrate statistical data, spatial models, earth observation satellite data, and climate modeling can be used to conduct strategic analyses for understanding the potential and efficiency of renewable energy development. This study aims to create the first spatial model of its kind in Southeast Asia to develop multi-renewable energy from solar, wind, and hydropower, further broken down into residential and agricultural areas. The novelty of this study is the development of a new priority model for renewable energy development resulting from the integration of area suitability analysis and the estimation of the amount of potential energy. Areas with high potential power estimations for the combination of the three types of energy are mostly located in northern Southeast Asia. Areas close to the equator, have a lower potential than the northern countries, except for southern regions. Solar photovoltaic (PV) plant construction is the most area-intensive type of energy generation among the considered energy sources, requiring 143,901,600 ha (61.71%), followed by wind (39,618,300 ha; 16.98%); a combination of solar PV and wind (37,302,500 ha; 16%); hydro (7,665,200 ha; 3.28%); a combination of hydro and solar PV (3,792,500 ha; 1.62%); and a combination of hydro and wind (582,700 ha; 0.25%). This study is timely and important because it will inform policies and regional strategies for transitioning to renewable energy, with consideration of the different characteristics present in Southeast Asia.

Green or not? Environmental challenges from photovoltaic technology.

The booming demands for energy and the drive towards low-carbon energy sources have prompted a worldwide emerging constructions of photovoltaic (PV) solar energy facilities. Compared with fossil-based electrical power system, PV solar energy has significantly lower pollutants and greenhouse gases (GHG) emissions. However, PV solar technology are not free of adverse environmental consequences such as biodiversity and habitat loss, climatic effects, resource consumption, and disposal of massive end-of-life PV panels. This review highlights the benefits and potential environmental impacts of implementing PV technologies. To the end, some proposals are recommended to improve this new technology's sustainability.

Challenges, strategies and opportunities for wind farm incorporated power systems: a review with bibliographic coupling analysis.

Wind power is a rapidly developing energy source. Many nations use wind power to meet a considerable amount of their energy needs. Moreover, the technology of wind power has evolved over the period of time. As a result, the wind farm-incorporated power system has received more attention for its outstanding contributions. The purpose of this study is to review the research works published on four key topics within the theme of wind farm-incorporated power systems. We survey the research papers that are featured in the Web of Science database. We employ an approach called Methodi Ordinatio to filter the papers. The publication of papers related to wind farm-incorporated power system has increased significantly, especially between 2018 and 2022. Therefore, we conduct a database search during this period and select important papers. Then we review and describe the technical challenges and solutions of these papers. Furthermore, a bibliographic coupling analysis is presented. The analysis shows that the journals such as Energy, Energies, and Renewable Energy are the leading journals publishing papers on all four key topics. The analysis further demonstrates that the focus of the researchers is on wind power forecasting, followed by energy storage systems, and wind farm layout optimization. The least focus is on optimal power flow.

Increased food availability at offshore wind farms affects trophic ecology of plaice Pleuronectes platessa.

Offshore wind farms (OWFs) and their associated cables, foundations and scour protection are often constructed in soft-sediment environments. This introduction of hard substrate has been shown to have similar effects as artificial reefs by providing food resources and offering increased habitat complexity, thereby aggregating fish around the turbines and foundations. However, as most studies have focused their efforts on fish species that are typically associated with reef structures, knowledge on how soft sediment species are affected by OWFs is still largely lacking. In this study, we analysed the trophic ecology and condition of plaice, a flatfish species of commercial interest, in relation to a Belgian OWF. The combination of a stomach and intestine content analysis with the use of biomarkers (i.e. fatty acids and stable isotopes) identified a clear shift in diet with increased occurrences of typical hard-substrate prey species for fish in the vicinity of the foundations and this both on the short and the long term. Despite some condition indices suggesting that the hard substrate provides increased food availability, no clear increases of overall plaice condition or fecundity were found. Samples from within the wind farm, however, contained larger fish and had a higher abundance of females compared to control areas, potentially indicating a refuge effect caused by the cessation of fisheries activities within the OWF. These results suggest that soft-sediment species can potentially benefit from the presence of an OWF, which could lead to fish production. However, more research is still needed to further elucidate the behavioral ecology of plaice within OWFs to make inferences on how they can impact fish populations on a larger spatial scale.

Using Alternative Sources of Energy for Decarbonization: A Piece of Cake, but How to Cook This Cake?

Few analytical or research works claim that the negative impact of improper use of ASEs may be comparable with that of hydrocarbons and sometimes even greater. It has become a common view that "green" energy (ASE) is clean, safe and environmentally friendly (eco-friendly) in contrast with "black" energy (hydrocarbons). We analyzed 144 works on systemic and/or comparative research of the modern and prospective ASE: biofuels, hydrogen, hydropower, nuclear power, wind power, solar power, geothermal power, oceanic thermal power, tidal power, wind wave power and nuclear fusion power. We performed our analysis within the Spaceship Earth paradigm. We conclude that there is no perfect ASE that is always eco-friendly. All ASEs may be dangerous to the planet considered as a closed and isolated unit ("spaceship") if they are used in an inconsistent manner. This is not in the least a reason to deny them as prospective sources of energy. Using all ASEs in different proportions in various regions of the planet, where their harm to the planet and humanity can be minimized and, on the contrary, their efficiency maximized, would give humanity the opportunity to decarbonize the Earth, and make the energy transition in the most effective way.

Impacts of accelerating deployment of offshore windfarms on near-surface climate.

The European Union has set the ambitious goal of becoming climate neutral by 2050, which has stimulated renewable energy production and accelerated the deployment of offshore wind energy in the North Sea. Here, a high-resolution regional climate model was used to investigate the impact on the sea surface climate of large-scale offshore wind farms that are proposed for the North Sea. The results show a significant reduction in the air-sea heat fluxes and a local, annual mean net cooling of the lower atmosphere in the wind farm areas down to more than 2.0 Wm-2, due to a decrease in 10 m wind speed and turbulent kinetic energy and an increase in low-level clouds. Mean surface winds decreased by approximately 1 ms-1 downstream of wind farms. Furthermore, an increase of approximately 5% in mean precipitation was found over the wind farm areas. At a seasonal timescale, these differences are higher during winter and autumn than in other seasons. Although the offshore wind farms reduce the heat transport from the ocean to the atmosphere in the region of large wind farms, the atmospheric layers below the hub height show an increase in temperature, which is on the order of up to 10% of the climate change signal at the end of the century, but it is much smaller than the interannual climate variability. In contrast, wind speed changes are larger than projected mean wind speed changes due to climate change. Our results suggest that the impacts of large clustered offshore wind farms should be considered in climate change impact studies. Moreover, the identified offshore windfarm impacts on the sea surface climate and the introduced spatial pattern in atmospheric conditions, in particular the modeled wind speed changes, suggest potential impacts on local ocean dynamics and the structure of the marine ecosystem. This should be considered in future scenarios for the North Sea marine environment and taken into account as a structuring influence in the offshore environment.

Biohydrogen in a circular bioeconomy: A critical review.

Hydrogen produced from biomass feedstocks is considered an effective solution in moving toward a decarbonized economy. Biohydrogen is a clean energy source that has gained global attention for adoption as it promises to mitigate climate change and human environmental damage. Through the circular economy framework, sustainable biohydrogen production with other bioproducts while addressing issues such as waste management is possible. This study presents a comprehensive review of the various biomass feedstocks and processing technologies associated with biohydrogen generation, as well as the possible integration of existing industries into a circular bioeconomy framework. The currently standing challenges and future perspectives are also discussed.

LSTM input timestep optimization using simulated annealing for wind power predictions.

Wind energy is one of the renewable energy sources like solar energy, and accurate wind power prediction can help countries deploy wind farms at particular locations yielding more electricity. For any prediction problem, determining the optimal time step (lookback) information is of primary importance, and using information from previous timesteps can improve the prediction scores. This article uses simulated annealing to find an optimal time step for wind power prediction. Finding an optimal timestep is computationally expensive and may require brute-forcing to evaluate the deep learning model at each time. This article uses simulated annealing to find an optimal time step for wind power prediction. The computation time was reduced from 166 hours to 3 hours to find an optimal time step for wind power prediction with a simulated annealing-based approach. We tested the proposed approach on three different wind farms with a training set of 50%, a validation set of 25%, and a test set of 25%, yielding MSE of 0.0059, 0.0074, and 0.010 for each wind farm. The article presents the results in detail, not just the mean square root error.

Pile driving repeatedly impacts the giant scallop (Placopecten magellanicus).

Large-scale offshore wind farms are a critical component of the worldwide climate strategy. However, their developments have been opposed by the fishing industry because of concerns regarding the impacts of pile driving vibrations during constructions on commercially important marine invertebrates, including bivalves. Using field-based daily exposure, we showed that pile driving induced repeated valve closures in different scallop life stages, with particularly stronger effects for juveniles. Scallops showed no acclimatization to repetitive pile driving across and within days, yet quickly returned to their initial behavioral baselines after vibration-cessation. While vibration sensitivity was consistent, daily pile driving did not disrupt scallop circadian rhythm, but suggests serious impacts at night when valve openings are greater. Overall, our results show distance and temporal patterns can support future mitigation strategies but also highlight concerns regarding the larger impact ranges of impending widespread offshore wind farm constructions on scallop populations.

Mapping county-level vulnerability to the energy transition in US fossil fuel communities.

The energy transition toward lower-carbon energy sources will inevitably result in socioeconomic impacts on certain communities, particularly those that have historically produced fossil fuel resources and electricity generation using fossil fuels. Such communities stand to lose jobs, tax revenues, and support for public services. Which communities are most likely to be affected, which are more susceptible to being harmed, and how to target adaptive capacity programs-such as economic development and workforce training-accordingly are pressing scholarly and policy questions. In this study, we apply a vulnerability framework to calculate, rank, and map exposure and sensitivity scores for fossil fuel producing regions in the US. We find that, while counties in most regions of the United States will be affected by the transition away from fossil fuels, counties in Appalachia, Texas and the Gulf Coast region, and the Intermountain West are likely to experience the most significant impacts, and some regions experience overlapping and significant incidence of vulnerability. These results can be used to target future adaptive capacity programs.

Recent Advancements and Challenges in Lignin Valorization: Green Routes towards Sustainable Bioproducts.

The aromatic hetero-polymer lignin is industrially processed in the paper/pulp and lignocellulose biorefinery, acting as a major energy source. It has been proven to be a natural resource for useful bioproducts; however, its depolymerization and conversion into high-value-added chemicals is the major challenge due to the complicated structure and heterogeneity. Conversely, the various pre-treatments techniques and valorization strategies offers a potential solution for developing a biomass-based biorefinery. Thus, the current review focus on the new isolation techniques for lignin, various pre-treatment approaches and biocatalytic methods for the synthesis of sustainable value-added products. Meanwhile, the challenges and prospective for the green synthesis of various biomolecules via utilizing the complicated hetero-polymer lignin are also discussed.

Considerations on environmental, economic, and energy impacts of wind energy generation: Projections towards sustainability initiatives.

The energy sector contributes significantly to the emission of greenhouse gases (GHGs) due to the use of fossil fuels which leads to climate change problems. Worldwide, there is a shift from fossil fuel-based energy to cleaner energy sources such as solar, wind, geothermal, and biomass. Wind energy is one of the promising cleaner energy sources as it is feasible and cost-effective. However, the development of wind farms causes impacts on sustainability aspects. This article aims to review the impacts of wind energy generation on environmental, economic, and social aspects of sustainability and their mitigation strategies. The aim was achieved by reviewing recent research papers on different aspects of wind energy sustainability. The environmental impacts reviewed include the effects on avian life, noise pollution, visual impacts, microclimate and vegetation. Apart from environmental impacts, wind energy generation faces issues in energy and financial sustainability, such as the wind power fluctuation, technology lagging and use of fixed feed-in tariff contracts that do not consider wind energy advancement and end-of-life management. We discussed that turbine deterrents, automatic curtailment, low gloss blades and sustainable siting of wind farms as some of the effective ways to combat wind energy environmental impacts. In addition, we discussed that energy storage systems, setting up microgrids, combination of solar, wind and energy storage, and renewable energies policies are some of the ways to combat wind energy's economic and energy impacts. Lastly, the recommendations, and future perspectives on wind energy generation sustainability are discussed.

Active power control strategy for wind farms based on power prediction errors distribution considering regional data.

One of the renewable energy resources, wind energy is widely used due to its wide distribution, large reserves, green and clean energy, and it is also an important part of large-scale grid integration. However, wind power has strong randomness, volatility, anti-peaking characteristics, and the problem of low wind power prediction accuracy, which brings serious challenges to the power system. Based on the difference of power prediction error and confidence interval between different new energy power stations, an optimal control strategy for active power of wind farms was proposed. Therefore, we focus on solving the problem of wind power forecasting and improving the accuracy of wind power prediction. Due to the prediction error of wind power generation, the power control cannot meet the control target. An optimal control strategy for active power of wind farms is proposed based on the difference in power prediction error and confidence interval between different new energy power stations. The strategy used historical data to evaluate the prediction error distribution and confidence interval of wind power. We use confidence interval constraints to create a wind power active optimization model that realize active power distribution and complementary prediction errors among wind farms with asymmetric error distribution. Combined with the actual data of a domestic (Cox's Bazar, Bangladesh) wind power base, a simulation example is designed to verify the rationality and effectiveness of the proposed strategy.

Behavioral and financial coping strategies among energy-insecure households.

When households struggle to pay their energy bills and avoid being disconnected from the grid, they may accrue debt, forgo expenses on food, and use space heaters or ovens to warm their homes. These coping strategies can introduce significant physical and financial risks. In this study, we analyze an original survey with a representative sample of low-income households during the first year of the COVID-19 pandemic, from June 2020 to May 2021. We evaluate the prevalence of a wide range of coping strategies and empirically estimate the determinants of these strategies. We find that more than half of all low-income households engage in at least one coping strategy, and many use multiple strategies. Households with vulnerable members, including young children or those who rely on electronic medical devices, and households that live in deficient housing conditions, are more likely to use a range of coping strategies, and many at once. Our findings have direct implications for public policy improvements, including modifications to the US Weatherization Assistance Program, the Low-Income Home Energy Assistance Program, and state utility disconnection protections.

The need for new metrics in the Anthropocene era.

A limitation in the discussion concerning climate change is the large degree of separation between scientific, economic, and technological approaches to tackle the crisis. This issue is most noticeable when considering the lack of metrics to measure the impact of different productive sectors on both the environment and the health of the population. The best-known attempt to measure these repercussions has been the introduction of the Environmental, Social and Governance (ESG) ratings for bonds. However, this rating system suffers from a lack of transparency and standardization. Moreover, it does not offer insights on the health impact and the regenerative effort of the evaluated bonds. Thus, we think it is necessary to introduce new metrics, focusing on at least four dimensions: circularity, climate change, biodiversity and health (including well-being). A sector that needs a special consideration is that of energy. To better compare different energy sources, we propose to adjust metrics such as the Energy Return on Investment (EROI) or the energy intensity metrics to include the negative health effects and the environmental degradation associated with producing energy. A similar index of return on investment corrected for health impacts may be considered to evaluate food production as well. Hyper-analytical and extremely focused approaches have dominated the discussion around the environmental crisis. We believe that a more inclusive approach is now needed, to highlight the potential co-benefits of different strategies, especially those that promote regeneration and a truly circular economy.