scholarly journals Future production of bioethanol from microalgae as a renewable source of energy

2021 ◽  
Vol 922 (1) ◽  
pp. 012010
Author(s):  
Wusnah ◽  
M. D. Supardan ◽  
S. Haryani ◽  
Yunardi

Abstract Fossil fuels that mainly supply the current increasing world’s energy demand originated from non-renewable resources. In addition to the depletion of their resources within the next short time, the combustion of fossil fuels to power industries and transportation also negatively impacts humans and the environment due to the release of various gaseous pollutants. To increase the share of renewables in the primary energy mix, the Government of Indonesia is currently struggling to meet a target of 23% by 2025. Therefore, more significant efforts to search for potential renewable energy sources are the only way to overcome this issue. Bioethanol is an eco-friendly renewable energy source since its combustion emits a low concentration of pollutants. Microalgae have gained significant interest in bioethanol production because of rapid biomass growth and relatively easy pre-treatment steps. It is renewable, carbon-neutral, sustainable and can be grown in wastewater coupling as wastewater treatment. This paper reviews bioethanol production, providing knowledge on the characteristics of microalgae potential for producing biomass to be converted into bioethanol, introducing process for bioethanol production, and presenting the potential challenges of bioethanol as a future renewable energy.

2010 ◽  
Vol 64 (4) ◽  
pp. 283-293 ◽  
Author(s):  
Zlatica Predojevic

The use of renewable energy sources (biofuels), either as a component in the conventional fossil fuels, gasoline and diesel, or as a pure biofuel, contributes to energy saving and decrease of total CO2 emission. The use of bioethanol mixed with gasoline significantly decreases gasoline consumption and contributes to environment protection. One of the problems in the production of bioethanol is the availability of sugar and starch based feedstock used for its production. However, lignocellulosic feedstocks are becoming more significant in the production of bioethanol due to their availability and low cost. The aim of this study is to point out the advantages and shortcomings of pretreatment processes and hydrolyses of lignocellulosic feedstocks that precede their fermentation to bioethanol.


2019 ◽  
Vol 11 (20) ◽  
pp. 5774 ◽  
Author(s):  
Karim ◽  
Karim ◽  
Islam ◽  
Muhammad-Sukki ◽  
Bani ◽  
...  

Bangladesh’s constant growth with an annual 6% plus Gross Domestic Product (GDP) for more than the last two decades and achievements in other socio-economic metrics in recent times is impressive and recognized by various global authoritative bodies. The extent of overwhelming economic ventures in the private sector coupled with the commitments of the government clearly demonstrates the transformation of the country from a primarily agro-based economy to one influenced by the manufacturing and service sectors. Bangladesh is fortunate to have fossil fuel reserves on a limited scale, though these are not enough to run the ongoing massive scale development activities, both in private and public sectors. Thus, the constant and uninterrupted supply of energy at an affordable price remains a serious concern for the successive governments. Therefore, this issue of supply of constant energy has turned to be an important part in the national development agenda. Besides, the country is one of the worst victim nations of the devastating effects of global warming and climate change. As Bangladesh is geographically located in a favorable place in the world map with the availability of plenty of renewable energy sources (RES), the policymakers started to take initiatives leading to exploiting these sources to meet the energy demand of the country. There are both prospects and administrative, legal, technological, socio-cultural and environmental challenges. To address these challenges, it requires comprehensive policy initiatives. A good number of technical and scientific research containing findings and recommendations are available. This paper, which is based on adopting a qualitative research methodology where the contents of secondary sources were analyzed, is an initial attempt to highlight the renewable energy developments in Bangladesh, and subsequently, to evaluate the relevant legal and policy initiatives in the light of international best practices. We advance several recommendations that the stakeholders can consider exploiting RES effectively to attain inclusive, equitable and sustainable development in Bangladesh. These include, inter alia: (1) Enhancing government participation to lead the development of renewable energy (RE); (2) ensuring localization of RE technology; (3) reducing the expenses of energy generation through RES and providing assistance in initial investments; (4) introducing comprehensive legal and regulatory policy for the development of RE industry in Bangladesh; and (5) conducting effective public awareness.


2018 ◽  
Vol 70 ◽  
pp. 01001
Author(s):  
Jacek Biskupski

This paper gives a thorough description of the two different scenarios of retrofit of an existing detached country house (with high primary energy demand) to a net zero energy building (nZEB) or near zero energy (nearZEB) by using energy form on-site RES. Using a designed piece of modelling software author pointed out two possible solutions. First one, based on a bio boiler and small on-site PV generator (on-grid) and the other based on large PV generator and three heat pumps. A 24 months test was performed in order to find out the output of both scenarios. In first period, the bio boiler delivered energy for space heating and DHW, while energy from PV was used to cover all electricity needs of the household during the 12 months testing period. In the later, the energy received from 10 kWp PV of was partly used to cover the current needs of the entire household (switchable on/off-grid system), and surplus was stored in the national electricity grid and regained later in the winter for the space heating (by a GSHP) and ventilation (ASHP) and DHW (dedicated ASHP). In both cases the system proofed the possibility to achieve the nZEB (nearZEB in first scenario) state of the household, as all (in the first near all) energy needs were covered by renewable energy produced on-site.


2020 ◽  
Vol 12 (16) ◽  
pp. 6312
Author(s):  
Rana Pratap Singh ◽  
Hans Peter Nachtnebel ◽  
Nadejda Komendantova

Nepal could rely on its huge renewable energy potentials to meet its energy demand sustainably. Also, renewable energy sources are considered by several national policy makers and international organizations as an engine for socio-economic development of the country, which can provide access to electricity to everybody and stimulate economic activity and economic growth. Several efforts were taken by the national government to stimulate deployment of renewable energy electricity generation capacities. However, the country is still not able to cover its energy needs with renewable energy despite decades of efforts for their deployment. The assumption of this research was that uncertainty in energy policy and planning gaps in Nepal are connected with the dominance of a limited number of discourses and ignorance of other voices which might be helpful. Nowadays, evidence exists that a multi-stakeholder and multi-sector perspective is extremely important for sustainable development. We provide evaluation of various perspectives, including technical, social, economic, environmental, and political. We collect empirical data in frames of a comprehensive stakeholders’ process in Nepal. The stakeholders’ preferences are analyzed through various methods of decision support sciences such as multi criteria decision analysis. To fast track hydropower development, the government has classified them into five categories based on their generation capacity. Assessment of each category and their collective comparison on multiperspectives has never been tried. Hence, such an assessment leading towards their prioritization is the objective of the study. It may help to identify a suitable strategy or policy to maximize national benefits. The study carried within the framework of five alternatives (categories) of hydropower schemes and nine different hydropower perspectives applicable in Nepalese context. The scoring method based is on secondary source evidence is applied for assessment. The study ranks medium schemes (25 to 100 MW) as best in Nepalese context.


2020 ◽  
Vol 172 ◽  
pp. 25004
Author(s):  
Marcin Zygmunt ◽  
Dariusz Gawin

Worldwide policy referring to global warming and air pollution assumes several main guidelines, in which Renewable Energy Sources (RES) usage simultaneously with limitation of fossil fuels in energy production seems to be a major goal. Nowadays, the continuous growth of RES usage within final energy consumption is becoming an obvious part of many country’s development. Adding to that relentless pursuit for improvement of building energy efficiency results in prediction, that in nearest future one should expect the development of advanced city-scale areas constituting an Energy Cluster. The paradigm of Energy Cluster (EC) allows us to define an energy flexibility neighbourhood. This article presents the results of energy analysis of a model neighbourhood of single-family houses with possible usage of RES. The neighbourhood constituting an EC was defined considering the Polish household sector statistical study. The analyzed area consists of representative single-family houses of Poland, characterized by different built periods, building shape and geometry as well as building enclosure parameters. Within the analysis, a detailed examination of a defined EC was performed by means of TEAC – computer tool developed by authors. TEAC is based on the results of energy simulations obtained by means of Energy Plus software and Artificial Neural Network (ANN) usage. Artificial Intelligence (AI) was used for energy demand predictions of buildings. Among possible RES a detailed analysis of solar and wind energy usage was performed. As a result, we obtained an hourly energy demand space- and time distribution, RES outputs, ecological analysis concerning greenhouse gasses emission and profitability analysis of proposed modernizations for the neighbourhood.


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 ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 202
Author(s):  
Mitja Mori ◽  
Manuel Gutiérrez ◽  
Mihael Sekavčnik ◽  
Boštjan Drobnič

Mountain huts are stand-alone micro-grid systems that are not connected to a power grid. However, they impact the environment by generating electricity and through day-to-day operations. The installed generator needs to be flexible to cover fluctuations in the energy demand. Replacing fossil fuels with renewable energy sources presents a challenge when it comes to balancing electricity generation and consumption. This paper presents an integration-and-optimization process for renewable energy sources in a mountain hut’s electricity generation system combined with a lifecycle assessment. A custom computational model was developed, validated with experimental data and integrated into a TRNSYS model. Five different electricity generation topologies were modelled to find the best configuration that matches the dynamics and meets the cumulative electricity demand. A lifecycle assessment methodology was used to evaluate the environmental impacts of all the topologies for one typical operating year. The carbon footprint could be reduced by 34% in the case of the actually implemented system upgrade, and by up to 47% in the case of 100% renewable electricity generation. An investment cost analysis shows that improving the battery charging strategy has a minor effect on the payback time, but it can significantly reduce the environmental impacts.


2019 ◽  
Vol 11 (7) ◽  
pp. 2136 ◽  
Author(s):  
Ceren Erdin ◽  
Gokhan Ozkaya

In Turkey, current energy generations are not sufficient for the existing energy needs and besides, energy demand is expected to increase by 4–6 percent annually until 2023. Therefore, the government aims to increase the ratio of renewable energy resources (RES) in total installed capacity to 30 percent by 2023. By this date, total energy investments are expected to be approximately $110 billion. Turkey is the fastest growing energy market among the OECD countries. Therefore, Turkey is an attractive market for energy companies and investors. At this stage, site selection and deciding appropriate RES are the most important feasibility parameters for investment. In this study, “Site Selection in Turkey” issue for RES (solar, wind, hydroelectric, geothermal, biomass) is evaluated by the ELECTRE which is one of the Multi Criteria Decision Making (MCDM) methods. In addition, the reasons for choosing this method are explained according to the literature. The study emphasizes the importance of energy generation from renewable and sustainable sources and is concerned with improving the position of the country. The Turkish government offers many purchasing guarantees and high incentives, especially in the renewable energy sector. As a result of the analysis, the most suitable energy sources are presented according to the geography and energy potential of the regions. The study aims to inform energy firms and everyone related with RES about Turkey’s RES opportunities.


2018 ◽  
Vol 8 (9) ◽  
pp. 1605 ◽  
Author(s):  
Szymon Firląg ◽  
Michał Piasecki

The main objective of this article is to propose possible requirements for NZEB (nearly zero-energy buildings) renovation definition in heating dominated climate. A survey was carried out on potential approaches and indicators that could be used for the NZEB definition of existing single-family houses in Poland. The process of determining requirements for the NZEB renovation definition was divided into two stages. The cost-optimal U-values of the building’s envelope were initially calculated and, based on them, the energy demand for heating (QH) and the reduction of non-renewable primary energy demand (QP) were estimated. The calculations were made for different energy prices, locations, and two building models. Based on them the requirements for cost-optimal renovation (QH ≤ 60 kWh/(m² year), QP reduction ≥ 75%) and NZEB renovation (QH ≤ 40 kWh/(m² year), QP reduction ≥ 80%) were proposed. In contrast to definitions using only a maximum level of QP, two indicators were used. Such a solution is appropriate for existing buildings because it prevents the situation in which only renewable energy sources (RES) (with a low primary energy factor) will be applied in order to decrease the primary, non-renewable energy demand.


Atmosphere ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1289
Author(s):  
M. Anwar H. Khan ◽  
Sophia Bonifacio ◽  
Joanna Clowes ◽  
Amy Foulds ◽  
Rayne Holland ◽  
...  

An accelerating global energy demand, paired with the harmful environmental effects of fossil fuels, has triggered the search for alternative, renewable energy sources. Biofuels are arguably a potential renewable energy source in the transportation industry as they can be used within current infrastructures and require less technological advances than other renewable alternatives, such as electric vehicles and nuclear power. The literature suggests biofuels can negatively impact food security and production; however, this is dependent on the type of feedstock used in biofuel production. Advanced biofuels, derived from inedible biomass, are heavily favoured but require further research and development to reach their full commercial potential. Replacing fossil fuels by biofuels can substantially reduce particulate matter (PM), carbon monoxide (CO) emissions, but simultaneously increase emissions of nitrogen oxides (NOx), acetaldehyde (CH3CHO) and peroxyacetyl nitrate (PAN), resulting in debates concerning the way biofuels should be implemented. The potential biofuel blends (FT-SPK, HEFA-SPK, ATJ-SPK and HFS-SIP) and their use as an alternative to kerosene-type fuels in the aviation industry have also been assessed. Although these fuels are currently more costly than conventional aviation fuels, possible reduction in production costs has been reported as a potential solution. A preliminary study shows that i-butanol emissions (1.8 Tg/year) as a biofuel can increase ozone levels by up to 6% in the upper troposphere, highlighting a potential climate impact. However, a larger number of studies will be needed to assess the practicalities and associated cost of using the biofuel in existing vehicles, particularly in terms of identifying any modifications to existing engine infrastructure, the impact of biofuel emissions, and their chemistry on the climate and human health, to fully determine their suitability as a potential renewable energy source.


Sign in / Sign up

Export Citation Format

Share Document