Acacia dealbata Link. Aboveground Biomass Assessment: Sustainability of Control and Eradication Actions to Reduce Rural Fires Risk

Invasive species are an environmental problem affecting worldwide ecosystems. In the case of Acacia dealbata Link., the negative impacts affect the productivity of the forests due to the competition established with native species while contributing to a significant increment in the available fuel load, increasing the risk of fire. In Portugal, chemical and mechanical methods are mostly used in the control of these species. However, the costs are often unsustainable in the medium term, being abandoned before completing the tasks, allowing the recovery of the invasive species. The establishment of value chains for the biomass resulting from these actions was pointed out by several authors as a solution for the sustainability of the control process, as it contributes to reducing costs. However, the problems in quantifying the biomass availability make it challenging to organize and optimize these actions. This work, which started from a dendrometrical analysis carried out in stands of A. dealbata, created a model to assess woody biomass availability. The model proved to be statistically significant for stands with trees younger than 20 years old. However, the amount of data collected and the configuration of the settlements analyzed do not allow extrapolation of the model presented to older settlements.

Estimation of Biomass Availability in Panglao Island Using SENTINEL-2 MSI

Remote Sensing (RS) technology using SENTINEL-2 Multispectral Instrument (MSI) imagery was used in the estimation of residual biomass’ available energy potential. The estimation was done in Panglao Island, within the province of Bohol, Philippines. Estimation of biomass availability was processed using Geographical Information System (GIS) software incorporating the calculation of Normalized Difference Vegetation Index (NDVI) to extract information on land resources and its spatial distribution. It was found that the majority of vegetation cover on the island is in the form of perennial woody plants and coconut trees. Coconut production on the island of Panglao contributed 1.26% of the total cultivation area for the province based on processed captures of Sentinel-2 imagery. The residue concentration amounted to 2,865 tons of coconut residues based on the RPR method. This amount of residues can be translated to 52.92 TJ of theoretical energy potential. The result of this study may serve as a baseline for the locality to consider the utilization of agricultural residues such as coming from coconut trees to support the use of indigenous resources for energy generation.

The current status, challenges and prospects of using biomass energy in Ethiopia

Despite enormous challenges in accessing sustainable energy supplies and advanced energy technologies, Ethiopia has one of the world's fastest growing economies. The development of renewable energy technology and the building of a green legacy in the country are being prioritized. The total installed capacity for electricity generation in Ethiopia is 4324.3 MW as on October, 2018. Renewable energy accounts for 96.5% of total generation; however, despite the county's enormous biomass energy potential, only 0.58% of power is generated using biomass. Ethiopia has surplus woody biomass, crop residue and animal dung resources which comprise about 141.8 million metric tons of biomass availability per year. At present the exploited potential is about 71.9 million metric tons per year. This review paper provides an in-depth assessment of Ethiopia's biomass energy availability, potential, challenges, and prospects. The findings show that, despite Ethiopia's vast biomass resource potential, the current use of modern energy from biomass is still limited. As a result, this study supports the use of biomass-based alternative energy sources without having a negative impact on the socioeconomic system or jeopardizing food security or the environment. This finding also shows the challenges, opportunities and possible solutions to tackle the problem to expand alternative energy sources. The most effective techniques for producing and utilizing alternate energy sources were also explored. Moreover, some perspectives are given based on the challenges of using efficient energy production and sustainable uses of biomass energy in Ethiopia as it could be also implemented in other developing countries. We believe that the information in this review will shed light on the current and future prospects of biomass energy deployment in Ethiopia.

A Study into the Availability, Costs and GHG Reduction in Drop-In Biofuels for Shipping under Different Regimes between 2020 and 2050

In this study, various scenarios were developed that correspond to estimations of future biomass availability and biofuel demand from the maritime industry. These marine biofuel demand scenarios were based on the Greenhouse Gas (GHG) reduction targets of the Renewable Energy Directive II (RED II) and the International Maritime Organization (IMO). A multi-objective Mixed Integer Linear Programming (MILP) model was developed which is used to optimize the Well-to-Tank (WtT) phases of each studied scenario. This resulted in an overview of the most feasible use of feedstocks, deployment of new conversion technologies and trade flows between regions. Additionally, the results provided insight into the costs and emission reduction potential of marine biofuels. By analyzing the results from this study, improved insight into the potential of drop-in biofuels for reaching the proposed emission reduction targets for the maritime sector was developed. A trade-off between costs and emissions was found to result in potential GHG reductions between 68–95% compared to Heavy Fuel Oil (HFO) for 800–2300 EUR/ton. More specifically, 80% GHG reduction compared to HFO can be achieved at fuel costs of between 900–1050 EUR/ton over the studied time period.

Analysis of the EU Secondary Biomass Availability and Conversion Processes to Produce Advanced Biofuels: Use of Existing Databases for Assessing a Metric Evaluation for the 2025 Perspective

Nowadays in Europe, the production of advanced biofuels represents a very important objective, given the strong interest in increasing sustainability throughout the transport sector. Production and availability of advanced biofuels are cited as a relevant issue in the most important international actions, such as the Sustainable Development Goals in UN Agenda 2030, EU RED II, and EU Mission Innovation 4, to cite a few of them. However, an important aspect to be considered is the prediction of feedstocks availability to produce advanced biofuel. The first aim of this paper is to assess the availability of European agricultural residues, forestry residues, and biogenic wastes in 2025. The data were collected through a deep review on open FAOSTAT and EUROSTAT databases and then elaborated by the authors. The analysis focuses on the fraction of feedstocks that can be used for advanced biofuels production, i.e., incorporating specific information on sustainable management practices, competitive uses, and environmental risks to preserve soil quality. An autoregressive model is developed to predict future availability, while also considering corrections due to the current pandemic. The results suggest that several European countries could produce enough sustainable advanced feedstocks to meet the European binding target. In particular, France, Germany, and Romania will have high production of agricultural feedstocks; while Austria, Finland, and Sweden will be rich of forestry residues; finally, Italy, France, and United Kingdom will have the highest availability of wastes. To complete the picture, a proper metric is introduced, aiming at generating a technology ranking of the examined alternative fuels, in terms of several relevant parameters such as biomass availability, Technology Readiness Level (TRL), quality of the biofuel, and costs. This analysis allows us to compare advanced biofuels and first-generation biofuels, whose utilization can impact the food market, while also contributing to the increase in the indirect land use change (ILUC). Although the first-generation biofuels remain the most common choice, the renewable (or green) diesel, pyrolysis bio-oil, green jet fuel, and the second-generation bioethanol are promising for different applications in the transport sector. Hydrotreated Vegetable Oils (HVO), Hydroprocessed Esters and Fatty Acids (HEFA), Anaerobic Digestion (AD), and transesterification from vegetable oil represent the most widespread and mature technologies. Thus, it seems mandatory that the transport sector will rely more and more on such fuels in the future. For such reason, a specific support for advanced biomass collection, as well as specific programs for conversion technologies development, are strongly suggested.

Eucalyptus globulus Coppices in Portugal: Influence of Site and Percentage of Residues Collected for Energy

Studies that quantify forest bioenergy potentials hardly address the questions of site quality, proportion and type of residues removed from the stands, and environmental impacts of those removals. However, those factors are important for energy-potential results and forest sustainability. This study compares, in terms of residual biomass availability for energy production and of sustainability, different locations, site indices, and forest management strategies in Eucalyptus globulus stands for pulp and paper in northern and central Portugal. A growth and production simulator was used to calculate the availability of residues and the area needed to supply a biomass-fired power plant under a variety of scenarios. Regions with more rainfall generate more residues, but site index and quantity and type of residues harvested are the most important factors. Under the different scenarios analyzed, the amount of residues potentially harvested range from 0.7 to 4.3 Mg ha−1 a−1, the upper bound corresponding to a scenario where stumps are valorized. The maximization of residue removal maximizes the bioenergy produced but has to be considered prudently. Studies indicate that stump removal has limited effect on Eucalyptus globulus stand productivity, diversity, and system sustainability, but impacts of residue removals increase with a decrease in site index.

Design of profitable networks of biogas plants in Chile

Locations for profitable biogas plant networks for the generation of electric power were investigated. A population-based location algorithm was developed. Using information regarding biogas power and plants cost found in the literature, together with data on the location and number of dairy cows of 572 farms in southern Chile, economic analises were made. Each farm was evaluated as a potencial location for a biogas plant, both alone and as part of different combinations. The algorithm starts with a population of one-plant combinations and generates new iterations by inserting additional biogas plants as long as the NPV increases. In each iteration, only a diverse subset of the combinations is selected. This approach is compared to the application of the ArcGIS Network Analyst (NA) function for the set cover problem, usually employed in the literature for biogas plant network location problems. Using the technical parameters for the operation of biogas plants found in the literature, we show that the proposed algorithm gives better results than the NA algorithm in terms of profit. Biogas plant networks were obtained for different scenarios of biomass availability (40–80%), energy sale prices (90–100 USD/MWh) and transport costs (0.3–0.4 USD/tkm). The results indicate that 18 of the 572 farms would be good candidates to site a biogas plant in at least one of the scenarios. A maximum of eight farms appear in a scenario with 80% of biomass availability and a transport cost of 0.3 USD/tkm. This solution reaches a NPV of USD 3,538,394, which exceeds by more than 70% the USD 2,075,057 obtained with the solution retrieved by the NA function. As the algorithm presented obtained better results than the ArcGIS network analyst, it can be used as an appropriate design tool for biogas plant networks.

A review on sustainability and quality of biochar production from oil palm biomass in Malaysia using thermal conversion technology

Oil palm empty fruit bunch (EFB), mesocarp fiber (MF), palm kernel shell (PKS), oil palm trunk (OPT) and oil palm frond (OPF) are the common solid lignocellulosic biomass generated from oil palm industries. A palm oil plantation was estimated to generate 36.5 ton of dry biomass in each hectare every year which suggesting the abundancy of these wastes. Feedstock feasibility and common properties as a carbon-rich material, have initiated an interest to utilize these biomass for biochar production. This paper provides a review on the developed thermal conversion technologies to synthesize biochar from oil palm biomass and includes the respective product quality such as carbon contents, yield and other physicochemical properties. The sustainability of oil palm biomass as the feedstock for biochar production in Malaysia were also described by providing the overview on biomass availability, biomass industry value chain and respective characteristics. Determining appropriate type of biomass and applying effective type of thermal conversion technologies produce biochar with good physicochemical qualities. This review observed that lignin in biomass contributes significantly to biochar production and slow pyrolysis technique is a promising technology to yield a good quality of biochar.