scholarly journals Optimization of biogas yield from lignocellulosic materials with different pretreatment methods: a review

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Kehinde Oladoke Olatunji ◽  
Noor A. Ahmed ◽  
Oyetola Ogunkunle

AbstractPopulation increase and industrialization has resulted in high energy demand and consumptions, and presently, fossil fuels are the major source of staple energy, supplying 80% of the entire consumption. This has contributed immensely to the greenhouse gas emission and leading to global warming, and as a result of this, there is a tremendous urgency to investigate and improve fresh and renewable energy sources worldwide. One of such renewable energy sources is biogas that is generated by anaerobic fermentation that uses different wastes such as agricultural residues, animal manure, and other organic wastes. During anaerobic digestion, hydrolysis of substrates is regarded as the most crucial stage in the process of biogas generation. However, this process is not always efficient because of the domineering stableness of substrates to enzymatic or bacteria assaults, but substrates’ pretreatment before biogas production will enhance biogas production. The principal objective of pretreatments is to ease the accessibility of the enzymes to the lignin, cellulose, and hemicellulose which leads to degradation of the substrates. Hence, the use of pretreatment for catalysis of lignocellulose substrates is beneficial for the production of cost-efficient and eco-friendly process. In this review, we discussed different pretreatment technologies of hydrolysis and their restrictions. The review has shown that different pretreatments have varying effects on lignin, cellulose, and hemicellulose degradation and biogas yield of different substrate and the choice of pretreatment technique will devolve on the intending final products of the process.

Author(s):  
Füsun Çelebi Boz ◽  
Turgut Bayramoğlu

Abstract The increase in population and urbanization which emerged together with industrialization have brought the increase in energy demand with them. Carbon emissions rise as a result of the increase in energy demand and lead to climate change. Such changes in climate have negative effects on not only the environment but human life as well. Therefore, countries should implement energy policies with low carbon density in order to reduce greenhouse gas emission. In this context, preferring renewable energy sources can prevent temperature increase by reducing the effects of fossil fuels on the environment. Turkey should attach importance to renewable energy sources and invest in these sources in accordance with the commitments accepted at the Paris Climate Summit in order to reduce carbon emission.


Energies ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2906 ◽  
Author(s):  
George E. Halkos ◽  
Eleni-Christina Gkampoura

The world’s ever-increasing population, combined with economic and technological growth and a new, modern way of life, has led to high energy demand and consumption. Fossil fuels have been the main energy source for many years, but their use has many negative impacts on the environment. This has made the transition to renewable energy sources necessary in order to address climate change and meet the 1.5 °C goal. This paper is a review of the different types of renewables, their potentials and limitations, and their connection to climate change, economic growth, and human health. It also examines consumers’ willingness to pay for renewables in different countries, based on the existing literature. IEA (International Energy Agency) data are analyzed, concerning renewables’ current use, the evolution of their usage, and forecasts about their future usage. Finally, policies and strategies are recommended in order to address climate change and fully integrate renewables as a sustainable energy source.


2021 ◽  
Author(s):  
Janis Millers ◽  
◽  
Irina Pilvere ◽  

With the adoption of the Green Deal in the European Union (EU), the role of biodiversity, basic principles of the circular economy, climate change mitigation, forest protection and renewable energy increased. Since 2007, biogas production in Latvia has increased significantly, as it was possible to receive co-funding from the EU Funds for the construction of biogas plants. In 2021, inputs of agricultural origin are used by 40 biogas plants with an average installed capacity of 1 MW. The emergence of biogas plants on livestock farms is facilitated by the development of a circular economy producing waste from the production process – manure and feed waste. Anaerobic fermentation results in digestate – a nutrient-rich plant fertilizer that reduces the application of chemical fertilizers. Rational use of biogas can reduce the need for fossil fuels. Energy production from biogas should be encouraged, as waste is used efficiently, thereby generating energy and reducing the release of greenhouse gases into the atmosphere. In Latvia, livestock production is one of the key industries of the national economy, which produces manure and feed waste. The present research calculated the amounts of cattle, pig and poultry manure and feed waste in Latvia. The research analysed livestock farms by number of cattle, pigs and poultry, the potential amounts of manure and waste produced and theoretical biogas output. Theoretically, 309 farms analysed can produce 93.5 mln. m3 of biogas from agricultural waste and construct 269 new biogas plants. A policy for supporting the construction of new biogas plants would contribute to the country’s independence from fossil energy sources, as well as increase the proportion of renewable energy sources to 50-70 % in final energy consumption by 2030. Farmers on whose farms a biogas plant could be built need to carefully consider the uses of the biogas produced. The uses could be thermal energy generation for heat supply, cogeneration (thermal and electrical energy) or biomethane production.


Author(s):  
Ümran Şengül ◽  
Sibel Tan ◽  
Şermin Atak ◽  
Ahmet Bilal Şengül

Energy is the ability to do work and life is the source of life. In parallel to the increase of population increase in the production of goods and services are increasingly in demand for energy. Evaluation of all sources of energy that can be produced now it has become very necessary. Widely used in meeting the energy demand of fossil fuels (oil, gas, coal) are limited energy resources and emissions are more harmful emissions. Spread of harmful emissions lessened even the most important problems is that they will end done day. From this perspective, the assessment of renewable energy sources in the world is an important issue. Gökçeada, Turkey is the largest island and the hills and plains lined one after the other, with a rugged structure consists of volcanic mass. Gökçeada consists of 77% mountainous, 12 % hilly and 11% plains and in terms of wind energy, which is the region with the greatest potential in Turkey. However, in terms of Gökçeada development index the least developed regions in the sixth regions, which is located in class. From this perspective, in this study, which will provide an important contribution to the region development of renewable energy sources wind, solar, tidal and renewable, biofuels and Hydraulics energy potential and capacity were investigated. Based on the data obtained, recommendations are made to invest in the renewable energy sector.


Nanoscale ◽  
2021 ◽  
Author(s):  
Woong Choi ◽  
Joon Woo Park ◽  
Woonghyeon Park ◽  
Yousung Jung ◽  
Hyunjoon Song

Electrochemical CO2 reduction reaction (eCO2RR) has been considered one of the potential technologies to store electricity from renewable energy sources into chemical energy. For this aim, designing catalysts with high...


Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 742
Author(s):  
Grzegorz Ślusarz ◽  
Barbara Gołębiewska ◽  
Marek Cierpiał-Wolan ◽  
Jarosław Gołębiewski ◽  
Dariusz Twaróg ◽  
...  

Energy obtained from renewable sources is an important element of the sustainable development strategy of the European Union and its member states. The aim of this research is, therefore, to assess the potential and use of renewable energy sources and their effectiveness from the regional perspective in Poland. The research covered the years 2012 and 2018. The diversification of production and potential of renewable energy sources was defined on the basis of biogas and biomass. Calculations made using the data envelopment analysis (DEA) method showed that, in 2012, only three voivodeships achieved the highest efficiency in terms of the use of biogas and biomass resources; in 2018, this number increased to four. Comparing the effective units in 2012 and 2018, it can be seen that their efficiency frontier moved upwards by 56% in terms of biogas and 21% in terms of to biomass. Despite a large relative increase in the production of heat from biogas by 99% compared to the production of heat from biomass by 38%, the efficiency frontier for biogas did not change considerably. It was found that the resources of solid biomass are used far more intensively than the resources of biogas. However, in the case of biogas, a significant increase in the utilization of the production potential was observed: from 3.3% in 2012 to 6.4% in 2018, whereas in the same years, the utilization of solid biomass production potential remained at the same level (15.3% in 2012, 15.4% in 2018). It was also observed that, at the level of voivodeships, the utilization of biogas and biomass production potential is negatively correlated with the size of this potential. The combined potential of solid biomass and biogas can cover the demand of each of the studied regions in Poland in terms of thermal energy. The coverage ranges from 104% to 1402%. The results show that when comparing biomass and biogas, the production of both electricity and heat was dominated by solid biomass. Its high share occurred especially in voivodeships characterized by a high share of forest area and a low potential for biogas production (Lubuskie Voivodeship, Zachodniopomorskie Voivodeship).


Author(s):  
Bisma Imtiaz ◽  
Imran Zafar ◽  
Cui Yuanhui

Due to the rapid increase in energy demand with depleting conventional sources, the world’s interest is moving towards renewable energy sources. Microgrid provides easy and reliable integration of distributed generation (DG) units based on renewable energy sources to the grid. The DG’s are usually integrated to microgrid through inverters. For a reliable operation of microgrid, it must have to operate in grid connected as well as isolated mode. Due to sudden mode change, performance of the DG inverter system will be compromised. Design and simulation of an optimized microgrid model in MATLAB/Simulink is presented in this work. The goal of the designed model is to integrate the inverter-interfaced DG’s to the microgrid in an efficient manner. The IEEE 13 bus test feeder has been converted to a microgrid by integration of DG’s including diesel engine generator, photovoltaic (PV) block and battery. The main feature of the designed MG model is its optimization in both operated modes to ensure the high reliability. For reliable interconnection of designed MG model to the power grid, a control scheme for DG inverter system based on PI controllers and DQ-PLL (phase-locked loop) has been designed. This designed scheme provides constant voltage in isolated mode and constant currents in grid connected mode. For power quality improvement, the regulation of harmonic current insertion has been performed using LCL filter. The performance of the designed MG model has been evaluated from the simulation results in MATLAB/ Simulink.


Author(s):  
Hanna Irena Jędrzejuk

This chapter describes a general issue of selecting renewable energy sources (RES) and technical systems. To achieve the nearly zero-energy building (nZEB) standard, application of an RES (e.g., solar, wind, geothermal, hydropower, and biomass energy) is necessary. Each type of RES has specific characteristics and can be used to produce electricity and/or heat in certain systems. A short review of various systems using renewable energy sources is presented. To find the required and satisfactory solution that guaranties meeting the nZEB standard, an analysis must be carried out considering a number of aspects: local availability, structure and time-dependence of energy demand, building construction, economic conditions, legal regulations, and specific requirements. Finally, two examples of modernisation towards the nZEB standard are included.


Energies ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 2051 ◽  
Author(s):  
Renato Lemm ◽  
Raphael Haymoz ◽  
Astrid Björnsen Gurung ◽  
Vanessa Burg ◽  
Tom Strebel ◽  
...  

The transition towards a reliable, sustainable, low-carbon energy system is a major challenge of the 21st century. Due to the lower energy density of many renewable energy sources, a future system is expected to be more decentralized, leading to significant changes at the regional scale. This study analyzes the feasibility of the energy transition in the Swiss canton of Aargau as an illustrative example and explores different strategies to satisfy the local demand for electricity, heat, and fuel by 2035. In particular, we assess the potential contribution of biomass. Four scenarios demonstrate what energy demand proportion could be covered by bioenergy if different priorities were given to the provision of heat, electricity, and fuel. The impact of improved conversion technologies is also considered. The results show that the sustainably available renewable energy sources in canton Aargau will probably not be sufficient to cover its forecasted energy demand in 2035, neither with present nor future biomass conversion technologies. At best, 74% of the energy demand could be met by renewables. Biomass can increase the degree of autarky by a maximum of 13%. Depending on the scenario, at least 26–43% (2500–5700 GWh) of total energy demand is lacking, particularly for mobility purposes.


Sign in / Sign up

Export Citation Format

Share Document