scholarly journals Energy Production from Forest Biomass: An Overview

Author(s):  
Ana Cristina Gonçalves ◽  
Isabel Malico ◽  
Adélia M.O. Sousa

As long as care is taken regarding stand and forest sustainability, forest biomass is an interesting alternative to fossil fuels because of its historical use as an energy source, its relative abundance and availability worldwide, and the fact that it is carbon-neutral. This study encompasses the revision of the state of the sources of forest biomass for energy and their estimation, the impacts on forests of biomass removal, the current demand and use of forest biomass for energy, and the most used energy conversion technologies. Forests can provide large amounts of biomass that can be used for energy. However, as the resources are limited, the increasing demand for biomass brings about management challenges. Stand structure is determinant for the amount of residues produced. Biomass can be estimated with high accuracy using both forest inventory and remote sensing. Yet, remote sensing enables biomass estimation and monitoring in shorter time periods. Different bioenergy uses and conversion technologies are characterized by different efficiencies, which should be a factor to consider in the choice of the best suited technology. Carefully analyzing the different options in terms of available conversion technologies, end-uses, costs, environmental benefits, and alternative energy vectors is of utmost importance.

2018 ◽  
Vol 11 (2) ◽  
pp. 66 ◽  
Author(s):  
Widdy Andya Fanny ◽  
S Subagjo ◽  
Tirto Prakoso

The Improvement of Calcium Oxide Catalyst for Biodiesel Synthesis The development of industrial’s sector resulted in increasing demand for fuel. Fuel used is obtained from fossil fuel which is limited, and it produces several harmful gases to environment. To overcome these obstacles, the research on alternative energy resources has begun. Biodiesel has become more attractive because of its environmental benefits and it is made from renewable resources. Biodiesel is produced from vegetable oil by transesterification reaction. The aim of this research is development of CaO become super base CaO as heterogeneous for biodiesel synthesis by transesterification. The activities of both catalysts were tested by transesterification reaction in batch reactor at 60–65 oC for 4 hours. Both of those catalysts were characterized; include crystallinity by XRD, strength of base and surface area by BET method. Those solids have the basic strength about 10–11, crystalline structures, and the surface area of super base CaO about 7.7 m2/g and CaO about 9.6 m2/g. The content of methyl ester in biodiesel produced reaches 98.8%. According to SNI (minimal 96.5 %-wt) and ASTM, biodiesel of this reaction can be used as renewable energy source. Keywords: CaO, super base CaO, transesterification, biodiesel Abstrak Berkembangnya industri di dunia mengakibatkan meningkatnya kebutuhan akan bahan bakar. Selama ini bahan bakar yang digunakan diperoleh dari bahan bakar fosil yang jumlahnya terbatas, terlebih lagi hasil pembakaran bahan bakar fosil cenderung tidak ramah lingkungan. Untuk mengatasi berbagai kendala yang ditimbulkan dari penggunaan bahan bakar fosil, penelitian terhadap sumber energi alternatif mulai dilakukan. Biodiesel menarik perhatian dunia karena hasil pembakarannya lebih ramah lingkungan dan berasal dari sumber yang terbarukan. Biodiesel dihasilkan dari minyak nabati melalui reaksi transesterifikasi.Penelitian ini mengembangkan katalis CaO menjadi katalis CaO super basa untuk reaksi transesterifikasi pembentukan biodiesel. Aktivitas katalis CaO dan katalis CaO super basa tersebut diuji melalui reaksi transesterifikasi di dalam reaktor partaian pada suhu 60–65 oC selama 4 jam. Karakterisasi padatan meliputi uji kristalinitas dengan metode XRD, uji kekuatan basa, dan uji luas permukaan dengan metode BET. Hasil penelitian menunjukkan bahwa padatan memiliki kekuatan basa berkisar 10–11, bersifat kristalin, dan memiliki luas permukaan sebesar 7,7 m2/g untuk CaO super basa dan 9,6 m2/g untuk CaO. Kadar metil ester biodiesel yang dihasilkan mencapai 98,8%. Kadar metil ester menurut SNI (minimal 96,5 %-b) dan ASTM, biodiesel dari reaksi ini dapat digunakan sebagai sumber energi terbarukan. Kata Kunci: CaO, CaO super basa, transesterifikasi, biodiesel


2018 ◽  
Vol 34 (1) ◽  
pp. 5-10 ◽  
Author(s):  
Han-Sup Han ◽  
Arne Jacobson ◽  
E.M. (Ted) Bilek ◽  
John Sessions

The Waste to Wisdom project was part of the Biomass Research and Development Initiative (BRDI) and funded by the Department of Energy (DE-EE0006297) at an amount of $5.8 million. Our interdisciplinary research team, consisting of academics, business professionals, and land managers, worked together for about four years (September 2013 to December 2017) to: 1) conduct field-based experiments to develop innovative tools and systems that improve the economics, accessibility, and production of quality feedstocks from forest residues, 2) develop and test stand-alone in-woods or near-the-forest biomass conversion technologies (BCTs) for the production of biochar, torrefied wood, and briquettes, and 3) perform analyses to evaluate the economic feasibility of commercial deployment of BCTs and to quantify the life cycle economic and environmental benefits of utilizing forest residues with BCTs for the production of bioenergy and bioproducts. The research papers presented in this Special Issue cover key aspects of the research efforts and findings made by the project team. We encourage the audience to visit the project web site (http://wastetowisdom.com/) to learn more about the team’s research on feedstock development, biomass conversion technologies, and the financial and environmental benefits of utilizing forest residues for production of bioenergy and biobased products. Keywords: Air quality, Biomass conversion technology, Forest harvesting, Woody biomass.


2015 ◽  
Vol 2 (1) ◽  
Author(s):  
Dominic van der Waals

AbstractRecent years have seen an increasing demand for fossil-fuels and consequent mounting damage to the environment. With this increasing demand the need for a renewable alternative source of energy is required. Hydrogen has been highlighted as an interesting alternative energy carrier showing both practical and economic advantages, particularly when used in conjunction with a hydrogen fuel cell [1]. Whilst there has been much progression in the clean and renewable production of hydrogen through; biomass gasification, photoelectrolysis and also electrolysis using energy derived from renewable sources [2,3], a challenge remains for the storage and delivery of hydrogen for small and mobile applications. This mini-review discusses a range of viable C1 hydrogen storage materials and focuses on the key publications, as well as recent additions to the literature, related to the ruthenium catalysed release of hydrogen as this is one of most intensively researched areas of the field. Current progress in the homogeneous ruthenium catalysed reduction of CO2 is also discussed.


2021 ◽  
Vol 45 ◽  
Author(s):  
Helena Cristina Carvalho Soares ◽  
Álvaro Nogueira de Souza ◽  
Edvaldo Pereira Santos Júnior ◽  
Anna Manuella Melo Nunes ◽  
Maísa Santos Joaquim ◽  
...  

ABSTRACT Faced with the transition in the global energy structure with the shift in consumption of fossil fuels to renewable and clean sources, there has been an increase in the demand for forest biomass for energy purposes, especially wood pellets, and imports have grown in recent years. Therefore, this study analyzed the world concentration of pellet imports from 2012 to 2018. Data on pellet imports were obtained from the Food and Agriculture Organization of the United Nations (FAO), and the following indicators were used to measure the concentration: Concentration Ratio [CR(k)], Hirschman-Herfindal Index (HHI), Theil Entropy Index (E), Gini Inequality Coefficient (G) and the Hall-Tideman Index (HTI). The results showed a growth of 16.67% p.a. of global pellet imports, from 8.76 million tons (t) in 2012 to 22.15 million tons in 2018. The CR(k) indicated very high concentration for countries and high in the subcontinents. The HHI showed a high concentration for continents and subcontinents and a moderate concentration for countries. Entropy and HTI corroborated the analyzes found in the HHI. The G pointed out strong inequality for all territorial levels and showed trends towards a reduction in inequality as of 2015. The reduction in the concentration in the final years of study is related to the expansion and technological diffusion of energy conversion of the densified biomass, which makes this fuel more affordable.


Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6209
Author(s):  
Behdad Shadidi ◽  
Gholamhassan Najafi ◽  
Talal Yusaf

The demand for fossil fuels is increasing because of globalization and rising energy demands. As a result, many nations are exploring alternative energy sources, and hydrogen is an efficient and practical alternative fuel. In the transportation industry, the development of hydrogen-powered cars aims to maximize fuel efficiency and significantly reduce exhaust gas emission and concentration. The impact of using hydrogen as a supplementary fuel for spark ignition (SI) and compression ignition (CI) engines on engine performance and gas emissions was investigated in this study. By adding hydrogen as a fuel in internal combustion engines, the torque, power, and brake thermal efficiency of the engines decrease, while their brake-specific fuel consumption increase. This study suggests that using hydrogen will reduce the emissions of CO, UHC, CO2, and soot; however, NOx emission is expected to increase. Due to the reduction of environmental pollutants for most engines and the related environmental benefits, hydrogen fuel is a clean and sustainable energy source, and its use should be expanded.


2020 ◽  
Vol 13 (1) ◽  
pp. 65
Author(s):  
Jingtao Li ◽  
Yonglin Shen ◽  
Chao Yang

Due to the increasing demand for the monitoring of crop conditions and food production, it is a challenging and meaningful task to identify crops from remote sensing images. The state-of the-art crop classification models are mostly built on supervised classification models such as support vector machines (SVM), convolutional neural networks (CNN), and long- and short-term memory neural networks (LSTM). Meanwhile, as an unsupervised generative model, the adversarial generative network (GAN) is rarely used to complete classification tasks for agricultural applications. In this work, we propose a new method that combines GAN, CNN, and LSTM models to classify crops of corn and soybeans from remote sensing time-series images, in which GAN’s discriminator was used as the final classifier. The method is feasible on the condition that the training samples are small, and it fully takes advantage of spectral, spatial, and phenology features of crops from satellite data. The classification experiments were conducted on crops of corn, soybeans, and others. To verify the effectiveness of the proposed method, comparisons with models of SVM, SegNet, CNN, LSTM, and different combinations were also conducted. The results show that our method achieved the best classification results, with the Kappa coefficient of 0.7933 and overall accuracy of 0.86. Experiments in other study areas also demonstrate the extensibility of the proposed method.


Author(s):  
Bikash Ranjan Parida ◽  
Somnath Bar ◽  
Nilendu Singh ◽  
Bakimchandra Oinam ◽  
Arvind Chandra Pandey ◽  
...  

To curb the spread of novel coronavirus (COVID-19), confinement measures were undertaken, which altered the pattern of energy consumption and India’s anthropogenic CO2 emissions during the effective lockdowns periods (January to June 2020). Such changes are being analyzed using data of energy generated from coal and renewable sources and fossil-based daily CO2 emissions. Results revealed that coal-fired (fossil-based) energy generation fell by –13% in March, –29% in April, and –20% in May, and –16.6% in mid-June 2020 as compared with the same period in 2018–2019. Conversely, the renewable energy generation increased by 19% in March, 12% in April, 17% in May, and 7% in June 2020. The share of fossil-based energy fell by –6.55% in 2020 compared with mean levels, which was further offset by increases of renewable energy. India’s daily fossil-based CO2 emissions fell by –11.6% (–5 to –25.7%) by mid-June 2020 compared with mean levels of 2017–2019 with total change in fossil-based CO2 emission by –139 (–62 to –230) MtCO2, with the largest reduction in the industry (–41%), transport (–28.5%), and power (–21%) followed by the public (–5.4%), and aviation (–4%) sectors. If some levels of lockdown persist until December 2020, both energy consumption and CO2 emissions patterns would be below the 2019 level. The nationwide lockdown has led to a reduction in anthropogenic CO2 emissions and, subsequently, improved air quality and global environment and has also helped in reducing atmospheric CO2 concentrations at the local level but not on the global level. With suitable government policies, switching to a cleaner mode of energy generation other than fossil fuels could be a viable option to minimize CO2 emissions under increasing demand for energy.


2012 ◽  
Vol 9 (8) ◽  
pp. 3381-3403 ◽  
Author(s):  
T. R. Feldpausch ◽  
J. Lloyd ◽  
S. L. Lewis ◽  
R. J. W. Brienen ◽  
M. Gloor ◽  
...  

Abstract. Aboveground tropical tree biomass and carbon storage estimates commonly ignore tree height (H). We estimate the effect of incorporating H on tropics-wide forest biomass estimates in 327 plots across four continents using 42 656 H and diameter measurements and harvested trees from 20 sites to answer the following questions: 1. What is the best H-model form and geographic unit to include in biomass models to minimise site-level uncertainty in estimates of destructive biomass? 2. To what extent does including H estimates derived in (1) reduce uncertainty in biomass estimates across all 327 plots? 3. What effect does accounting for H have on plot- and continental-scale forest biomass estimates? The mean relative error in biomass estimates of destructively harvested trees when including H (mean 0.06), was half that when excluding H (mean 0.13). Power- and Weibull-H models provided the greatest reduction in uncertainty, with regional Weibull-H models preferred because they reduce uncertainty in smaller-diameter classes (≤40 cm D) that store about one-third of biomass per hectare in most forests. Propagating the relationships from destructively harvested tree biomass to each of the 327 plots from across the tropics shows that including H reduces errors from 41.8 Mg ha−1 (range 6.6 to 112.4) to 8.0 Mg ha−1 (−2.5 to 23.0). For all plots, aboveground live biomass was −52.2 Mg ha−1 (−82.0 to −20.3 bootstrapped 95% CI), or 13%, lower when including H estimates, with the greatest relative reductions in estimated biomass in forests of the Brazilian Shield, east Africa, and Australia, and relatively little change in the Guiana Shield, central Africa and southeast Asia. Appreciably different stand structure was observed among regions across the tropical continents, with some storing significantly more biomass in small diameter stems, which affects selection of the best height models to reduce uncertainty and biomass reductions due to H. After accounting for variation in H, total biomass per hectare is greatest in Australia, the Guiana Shield, Asia, central and east Africa, and lowest in east-central Amazonia, W. Africa, W. Amazonia, and the Brazilian Shield (descending order). Thus, if tropical forests span 1668 million km2 and store 285 Pg C (estimate including H), then applying our regional relationships implies that carbon storage is overestimated by 35 Pg C (31–39 bootstrapped 95% CI) if H is ignored, assuming that the sampled plots are an unbiased statistical representation of all tropical forest in terms of biomass and height factors. Our results show that tree H is an important allometric factor that needs to be included in future forest biomass estimates to reduce error in estimates of tropical carbon stocks and emissions due to deforestation.


2011 ◽  
Vol 37 (6) ◽  
pp. 596-611 ◽  
Author(s):  
Hans-Erik Andersen ◽  
Jacob Strunk ◽  
Hailemariam Temesgen ◽  
Donald Atwood ◽  
Ken Winterberger

Author(s):  
Kau-Fui Vincent Wong ◽  
Guillermo Amador

As society continues advancing into the future, more energy is required to supply the increasing population and energy demands. Unfortunately, traditional forms of energy production through the burning of carbon-based fuels are dumping harmful pollutants into the environment, resulting in detrimental, and possibly irreversible, effects on our planet. The burning of coal and fossil fuels provides energy at the least monetary cost for countries like the US, but the price being paid through their negative impact of our atmosphere is difficult to quantify. A rapid shift to clean, alternative energy sources is critical in order to reduce the amount of greenhouse gas emissions. For alternative energy sources to replace traditional energy sources that produce greenhouse gases, they must be capable of providing energy at equal or greater rates and efficiencies, while still functioning at competitive prices. The main factors hindering the pursuit of alternative sources are their high initial costs and, for some, intermittency. The creation of electrical energy from natural sources like wind, water, and solar is very desirable since it produces no greenhouse gases and makes use of renewable sources—unlike fossil fuels. However, the planning and technology required to tap into these sources and transfer energy at the rate and consistency needed to supply our society comes at a higher price than traditional methods. These high costs are a result of the large-scale implementation of the state-of-the-art technologies behind the devices required for energy cultivation and delivery from these unorthodox sources. On the other hand, as fossil fuel sources become scarcer, the rising fuel costs drive overall costs up and make traditional methods less cost effective. The growing scarcity of fossil fuels and resulting pollutants stimulate the necessity to transition away from traditional energy production methods. Currently, the most common alternative energy technologies are solar photovoltaics (PVs), concentrated solar power (CSP), wind, hydroelectric, geothermal, tidal, wave, and nuclear. Because of government intervention in countries like the US and the absence of the need to restructure the electricity transmission system (due to the similarity in geographical requirements and consistency in power outputs for nuclear and traditional plants), nuclear energy is the most cost competitive energy technology that does not produce greenhouse gases. Through the proper use of nuclear fission electricity at high efficiencies could be produced without polluting our atmosphere. However, the initial capital required to erect nuclear plants dictates a higher cost over traditional methods. Therefore, the government is providing help with the high initial costs through loan guarantees, in order to stimulate the growth of low-emission energy production. This paper analyzes the proposal for the use of nuclear power as an intermediate step before an eventual transition to greater dependence on energy from wind, water, and solar (WWS) sources. Complete dependence on WWS cannot be achieved in the near future, within 20 years, because of the unavoidable variability of these sources and the required overhaul of the electricity transmission system. Therefore, we look to nuclear power in the time being to help provide predictable power as a means to reduce carbon emissions, while the other technologies are refined and gradually implemented in order to meet energy demand on a consistent basis.


Sign in / Sign up

Export Citation Format

Share Document