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One of the alternatives for effective storage of irregularly produced renewable energy is hydrogen energy. In order to realize a hydrogen-based society, not only environmentally friendly production of hydrogen but also effective storage is very important. Underground hydrogen storage technology is a technology that has evolved from the technology for storing natural gas underground, and includes waste gas fields, salt domes, aquifers, and rock cavities. When stored underground, hydrogen is converted into high-pressure gaseous hydrogen, liquefied hydrogen, and ammonia. Liquefied hydrogen requires extremely low storage temperatures, and ammonia is a toxic substance that requires separate handling, and energy loss occurs during the conversion process. To compensate for this, research on liquefied hydrogen, such as multilayer insulation technology, is being conducted. Ammonia has successfully extracted high-purity hydrogen by developing a membrane reactor. Ammonia toxicity can be prevented by strengthening leak detection and blocking facilities. Among these, ammonia was found to be the most suitable for underground storage in terms of economic feasibility, environment, and commercialization.

Natural hydrogen is green hydrogen that is naturally produced on Earth, that is, an energy source that does not emit carbon without using additional energy for production. Since carbon is emitted from the existing gray hydrogen and blue hydrogen, green hydrogen with perfect eco-friendliness has been required. Natural hydrogen is produced through four mechanisms: serpentinization, radioactive decomposition, magma gas removal, and rock destruction and can exist in the dissolved ․ content of fluid mammals. Representative sites discovered to date include Mali, Africa, Brazil, and Australia, and each topography has different characteristics. Although reserves are estimated using geochemical and geophysical exploration technologies, the reliability is not high because the deep hydrogen flow in various geological environments is not considered. Based on this, this study drew the following conclusions. 1) Hydrogen can realize carbon neutrality with high energy content and independence, but 2) economic feasibility cannot be evaluated due to the uncertainty of the reserves and current reserves of natural hydrogen. Therefore, 3) for commercial use, leakage detection technology is required along with an understanding of the mechanism for generating natural hydrogen.

Offshore wind power generation is recognized as an environmentally friendly and sustainable energy source, rapidly advancing with governmental support in many countries such as Denmark, China, Germany, and across Europe due to its high energy stability, potential, and economic benefits. South Korea has set a target of 17.7GW for wind power generation through its Renewable Energy 3020 Implementation Plan, aiming to supply 12GW of offshore wind power by 2030. However, Korea faces slower development compared to overseas counterparts due to various obstacles including lack of community acceptance, low business feasibility, complex approval processes, and insufficient supply chain. This study identifies fundamental reasons behind Korea's sluggish growth in offshore wind power generation and proposes the following solutions through comparison with leading international cases. 1) Strengthening positive communication with residents by clearly articulating the value and benefits of offshore wind power projects to address community acceptance issues. 2) Resolving low business feasibility issues through the establishment of government-led incentive programs and support measures. 3) Streamlining approval processes to mitigate delays and cancellations in project implementation. 4) Expanding domestic market size and enhancing efficient power interconnection to address supply chain deficiencies.

Pyrolysis is a technology that can produce pyrolysis oil by decomposing waste plastic, and has the advantage of being able to process contaminated waste plastic that is impossible to process with other technologies. In Korea, where the amount of waste plastic is increasing and natural resources such as fossil fuels are lacking, pyrolysis technology is attracting attention under the keyword ‘urban oil field’. The Ministry of Environment of the Republic of Korea announced a ‘plan to revitalize waste plastic pyrolysis’ to increase the proportion of waste plastic pyrolysis treatment from 0.1% in 2021 to 10% in 2030. The products of pyrolysis are both fuel and plastic raw materials, but the processing consumes significant energy. Therefore, as criticism continues that the marketability and economic feasibility of pyrolysis technology is poor, questions are being raised about its environmental friendliness. Against this background, this study investigated international trends in pyrolysis technology and performed a detailed comparative analysis with other technologies from an environmental perspective. According to the results of this study, currently environmentally advanced countries are very negative about using pyrolysis oil as fuel, and the following policy directions are suggested. 1) In order to comply with the mandatory use ratio of plastic recycled raw materials and at the same time achieve eco-friendliness, it is recommended to use pyrolysis technology as a plastic recycled raw material production technology rather than fuel conversion. 2) Since pyrolysis emits more greenhouse gases than physical recycling, pyrolysis technology is used as a complementary method to physical recycling to process waste plastics that are difficult to physically recycle. 3) Since physical recycling is very important in the resource circulation of waste plastic, the development of separation and sorting technology is promoted nationally.

Environmental issues are the biggest issues in modern society. Among them, the development of technologies to solve the chain of environmental problems caused by excessive waste and depletion of resources due to overconsumption of energy is continuously taking place. Accordingly, technologies that can produce and utilize alternative fuel oil using raw materials such as waste and biomass are attracting a lot of attention as a solution. Crude oil extraction technology is a technology currently under development along with gasification technology, and is a technology that is attracting attention because it can obtain energy resources from waste or other raw materials. In this study, the raw materials used for crude oil extraction were analyzed, and the definitions, characteristics, principles, and processes of four crude oil extraction technologies were examined. In addition, the current trends of each technology were identified and organized, and the environmental impact and performance strengths compared to existing fuels were identified as the evaluation of each technology. Finally, based on the analysis of the surveyed contents, a comprehensive evaluation of the current crude oil extraction technology was conducted, and the prospects of crude oil extraction technology in the long and short term were discussed.

This paper focuses on the crucial role of solar power generation in addressing global warming. It examines South Korea's solar technology, which demonstrates high proficiency at approximately 90% (EU standard) and outperforms the EU in system operation and maintenance. Despite China's lower technological score (87.5%), its competitive pricing has led to an increase in the market share of Chinese products, eroding South Korea's competitiveness. The research identifies cost issues compared to coal and explores avenues for improvement, particularly in direct and indirect cost aspects. In the direct cost domain, proposals include establishing solar cell production facilities in countries with low labor costs and favorable tax incentives to reduce equipment costs. In the indirect cost domain, suggestions involve leveraging building-integrated solar and unused land to cut permit and financial expenses. The paper highlights reasons for the inadequate adoption of building-integrated solar in South Korea, such as mortgage issues, pricing constraints due to the System Marginal Price (SMP) system, and the limited deployment of microgrids. Emphasis is placed on the activation of microgrids, introducing new transaction methods and promoting efficient power transactions through infrastructure. These efforts are expected to lead to the sustained growth of the solar power generation industry in the future.

Alternative meat is a protein food produced by cultivating animal cells, processing insects, and extracting vegetable raw materials, rather than slaughtering animals, and has been suggested as an alternative to conventional meat to solve the current factory farming and animal rights problems. The global alternative meat market is expected to reach $29 billion by 2035 from $1.78 billion in 2025. Alternative meat has significantly lower water and land use and greenhouse gas emissions compared to conventional meat production methods and is free from the emerging animal ethics problem. However, with the current technology, there is a limit to reproducing the taste, texture, and nutritional content of actual meat, so continuous technology development is needed. The negative perception of some consumers and the absence of alternative meat-related systems are also challenges to be solved. This paper deals with the types, characteristics, market status, and the latest technology trends of alternative meat. In addition, we aim to contribute to the development and establishment of alternative meat by looking at alternative meat from the perspective of consumption and investigating the challenges that the alternative meat industry must solve to establish itself as a future food source.

Just as fast food is produced and consumed quickly, fast fashion, which mass produces and sells clothing by quickly chasing the latest trends targeting the global market, forms an axis of the clothing industry. However, in the fast fashion ecosystem, clothing is mass-produced and easily discarded, and the resulting environmental problems are becoming a social concern. Recently, consumers' environmental awareness has been increasing, and as ESG management that focuses on the environment has emerged, the clothing industry is also responding strategically to the changed environment, including eco-friendly production methods, use of eco-friendly materials, and recycling of inventory. In this way, this review analyzed the current status and problems of fast fashion and social responses to it, and suggested measures that society should pursue for an eco-friendly clothing industry in the future.

As environmental problems such as climate and resource depletion are seriously occurring worldwide, the climate crisis and environmental problems are drawing attention throughout society. Reflecting this reality, an increasing number of ESG management companies are promoting environmentally friendly products and conducting eco-friendly marketing to secure corporate competitiveness. Unfortunately, however, greenwashing marketing by companies that exploit society's preference for eco-friendly companies is also rapidly increasing. Greenwashing refers to camouflage environmentalism that is not actually environmentally friendly but appears to be environmentally friendly. Through this review, we will find out the beginning and meaning of greenwashing and try to explain the seriousness of greenwashing through cases of greenwashing that occurred in the aspects of the country, companies, and consumers. The trend of global regulation on greenwashing was examined, and through this, policy measures to suppress greenwashing were presented.

In the process of implementing and trying various measures to achieve carbon neutrality around the world, Korea is also presenting various policies to advance to a low-carbon economy. Energy prosumer is a consumer who produces electricity directly and sells surplus electricity after consumption through an electric power company. Currently, advanced countries such as the U.S. and Germany are developing various business models beyond the initial energy prosumer model. However, in Korea, it is difficult for individuals to directly participate in the electricity market and buy and sell electricity due to policy limitations and complex reasons. In addition to these problems, low electricity bills and relatively high solar power prices are factors that hinder energy prosumers. Basically, in order for energy prosumers to be activated, the unit price of solar power must be lower than the unit price of electricity bill. In addition, an electricity market must be formed in which individuals can freely trade, and policies and legislation must be prepared to support them. If such a step is prepared to revitalize energy prosumers, energy self-sufficiency will be possible and a new energy industry will be established. Ultimately, decentralized resource systems such as smart grids are activated, enabling carbon neutrality. As the unit price of solar power in Korea has fallen and electricity bills are on the rise, energy prosumer’s prospects are positive. If the electricity bill system is implemented first through restructuring of the electricity industry, it will be possible to establish the energy prosumer system in Korea while trying to develop various energy prosumer business models and transaction methods.

The modern society is developing rapidly, and humanity is facing unprecedented environmental pollution, global warming, climate change and various environmental problems. As a result, companies, a key social organization in modern capitalist society, are increasingly taking environmental and social responsibility. ESG management is an enterprise management that emphasizes non-financial factors (environment, society and corporate government). Recently, ESG considerations have become increasingly important in corporate management and investment. In preparation for this situation, companies are continuously releasing sustainability report to improve internal systems and build systems. As society is paying keen attention to ESG management, the number of actual management cases is increasing. However, in proportion to this interest, cases of greenwashing, which can be called fake eco-friendly marketing, have also been discovered, such as eco-friendly products or exaggerated carbon emission reductions. Accordingly, the comprehensive review examined cases of environmental factors in ESG management for overseas evaluation agencies that provide ESG management and related standards. In addition, a plan was proposed to establish sustainable corporate management using comprehensive domestic evaluation criteria.

Products introduced as vegan are recognized by consumers as ethical consumption that protects animals and the environment, so they are becoming a trend in recent marketing strategies. However, consumers are confused by the claim that veganism consumption is not environmentally friendly, contrary to consumers' perception of animal protection and environmental protection. Vegan leather, which appeared as an alternative to natural leather, emits harmful substances during the manufacturing and disposal process, is less durable than natural leather, and has a shorter lifespan, resulting in a problem of fast fashion. Substitute meat is emerging as a food of the future due to environmental problems caused by raising livestock. However, considerable carbon is generated during the production of substitute meat, and there is a problem in verifying the safety of fiber materials such as various additives used during the production process. In the case of vegan cosmetics, they use only eco-friendly ingredients derived from nature instead of animal ingredients and do not test on animals, so the impact on the environment is minimal. Overall, bigonomics products generate relatively less environmental pollutants and cause less environmental pollution, but there are still limitations to be overcome. It is thought that the limitations of bigonomics can be overcome through social collective practice such as education and investment in parallel with individual practice in daily life. Furthermore, I think that if there is a correct understanding of vegannomics and communication about its value, the vegan industry will be able to take its place as a major industry in society. In this review, the current status of bigonomics in the food, cosmetics, and fashion industries, which are being developed by consumers' ethical consumption, is reviewed and prospects are presented. This review will help set the direction in each industry pursuing vigenomics.

As sales of electric vehicles rapidly increase, the amount of waste batteries is also rapidly increasing. Accordingly, social interest in the recycling and reuse of waste batteries is rapidly increasing. Waste battery recycling refers to the process of reprocessing waste batteries and extracting valuable water for reuse. Reuse of waste batteries refers to the process of using them again for the same purpose after undergoing a slight conversion process. Currently, related technology development is required, and related policies are insufficient. Looking at the global trend, a waste battery collection system is being established through the labeling system and producer responsibility recycling system, battery performance and safety evaluation standards are being established, and efficient and safe transportation systems are being established. Since it is not clear who is responsible for each stage of the problem in the disposal of waste batteries, a history management system is needed. It is important to efficiently extract and recycle waste battery resources, but it is also necessary to develop battery technology free from resource scarcity. In this review, recycling and reuse-related technologies of waste batteries, battery-related policies, and rare metal replacement technologies were explored, and directions for future waste battery policies were presented.

Recently, there has been an increasing national interest in air pollutants including fine dust due to worsening air quality. As more people become interested in the environment, policies that consider the environment are being implemented in various fields as regulations also change. It can be seen that regulations are being strengthened as the MARPOL standards for air pollutants such as sulfur oxides, nitrogen oxides, carbon dioxide, EEDI are being lowered. According to the United Nations Conference on Trade and Development, 80% of goods trade is transported by ships and the amount of air pollutants emitted by ships cannot be overlooked. Therefore, there is a growing need to transition from traditional fossil fuel-powered mechanical ships to eco-friendly ships. In this review, we analyze one type of eco-friendly ship, the electric ship. We compare the economic viability of electric ships with traditional mechanical ships and investigate the current status and commercialization cases of electric ships. We also provide insights into the future prospects of electric ships.

Nuclear power generation, which began in the Soviet Union in June 1954, has now become a main source of electrical energy in 33 countries around the world. However, radioactive waste and its safety have always been at the center of controversy, and even after 70 years, there is no official regulation on the disposal of radioactive waste under international law. In this review, the policies and current status of radioactive waste disposal in major countries around the world, including Korea, are investigated. Based on this, the direction for radioactive waste management in Korea was presented. Currently, radioactive waste is disposed of in two ways. Finland, Sweden, and France are conducting deep permanent disposal according to the recommendation of the International Atomic Energy Agency, and Japan, the United Kingdom, and India are promoting reprocessing of spent nuclear fuel to reduce waste and the volume of the repository. Korea has been temporarily storing radioactive waste at the site of the power plant since the completion of Kori Unit 1 in 1978, but it is expected that the capacity of the temporary storage facility will reach its limit in 2031. Accordingly, the securing of a permanent disposal site and the development of reprocessing technology are being studied together, but no tangible results have been achieved so far. Korea's radioactive waste disposal has problems such as a small land area, institutional difficulties in developing reprocessing technology, frequent policy changes, ignorance and indifference, and lack of smooth communication. Although public concern about nuclear power generation has increased due to the Fukushima disaster, not many people are interested in spent nuclear fuel. Within the framework of reprocessing and permanent disposal, Korea should refrain from frequent policy changes that can confuse public opinion and research and development, and come up with a long-term realistic policy.

The world is gripped with a sense of crisis over the disasters caused by rapid climate change. Various policy and technical attempts are being made to reduce carbon emissions around the world. Since the issue of RE100 was raised in the last presidential debate, interest in RE100 has been increasing. RE100 is a voluntary campaign to cover corporate power with 100% renewable electricity, and is attracting more attention in line with the company's sustainable management policy. In this review, the reality of RE100 and related policies were investigated. Based on this, the institutional direction for the realization of RE100 was presented.

Korea consumes a large amount of energy. Korea is vulnerable to energy security due to its high dependence on energy imports. The amount of waste generated in South Korea is increasing every year. Recycling accounted for the highest proportion of waste disposal methods at 86.6%, but this was calculated based on the amount brought into recycling facilities. In fact, large amounts of waste are landfilled or incinerated. Landfilling and incineration of waste causes various environmental pollution problems. We need innovative and practical technologies that convert waste into energy and have less impact on the environment. Waste gasification technology is currently attracting attention because it emits less pollutants and can produce energy using waste as a raw material. In this review, we briefly summarized the principles and characteristics of the gasification process, and discussed the current status and limitations of waste gasification process equipment in Japan and overseas, and the direction that should be taken from the technical and institutional aspects.

Globally, interest in renewable energy and related industries are rapidly increasing in recent years. In solar power generation, almost unlimited energy resources can be supplied as long as the sun does not disappear, and carbon dioxide is not generated when looking at the power generation process itself. However, photovoltaic power generation faces several fundamental problems such as low economic feasibility, disposal of waste panels, environmental destruction due to installation, and generation of harmful substances in the production process. In this review, the current status of photovoltaic power generation is reviewed and, based on this, the direction for Korea's photovoltaic policy is suggested. 1) In order to overcome low economic feasibility, large-scale power generation projects should be promoted to achieve economies of scale. 2) Existing buildings or spaces must be utilized to prevent forest damage from photovoltaic power generation. 3) Active support and investment from the state and companies are needed to develop eco-friendly technologies for reducing hazardous substances and recycling waste panels. 4) An institutional system for information disclosure and management of harmful substances for solar energy projects should be established.

As climate change progresses rapidly, unprecedented weather and natural changes are occurring. After carbon dioxide was identified as the main culprit of global warming and climate change, at the UN General Assembly in 2015, 195 countries signed the Paris Agreement to set greenhouse gas emission reduction targets. However, some countries are either withdrawing from the Paris Agreement or failing to implement it due to their own economic reasons. Reducing the use of fossil fuels increases energy costs. In this context, carbon capture and storage technology (CCS) is emerging as an alternative. In this review, the outline of CCS technology is explained, and the advantages and disadvantages of each technology, the status of CCS technology, and commercialization cases are investigated and analyzed. In addition, for an in-depth analysis of the CCS technology itself, the following issues were analyzed in depth during the research and analysis process: 1) Efficiency of CCS technology, 2) Comparison of carbon capture and storage capacity between CCS technology and vegetation, 3) Stability of carbon storage through CCS technology. Finally, the policy for carbon capture and storage technology and the development direction of this technology were presented.

As the COVID-19 pandemic and interest in the virtual world rapidly increase, the data usage in the current society is rapidly increasing to an unprecedented level, and the need for expansion of data centers to handle it is also rapidly increasing. Data centers operate continuously and consume a lot of power in operation. As electricity consumption increases, the increase in greenhouse gas emissions adversely affects the environment, so the increase in data centers inevitably affects the climate environment. Typical technologies that can reduce power consumption in data centers are waste heat energy utilization and outdoor air conditioning. By analyzing the cases of major countries for the two technologies, the technological direction beneficial to Korea was reviewed. As Korea's outdoor air conditioning standards are relaxed, the number of outdoor air conditioning facilities in Korea is increasing. However, the Korean government's practical support for waste heat energy utilization is extremely limited. By analyzing policy cases for waste heat energy utilization in data centers in other countries, policies for revitalizing waste heat energy utilization in Korean data centers were proposed. Furthermore, several ways to reduce the amount of power in the data center were explored and proposed.

A sediment microbial fuel cell (SMFC) is a system in which MFC is applied to a sediment layer of an aqueous system for water purification. SMFCs can remove contaminants from sediments and decompose organic matter while simultaneously producing electrical energy. SMFC is installed in the form of installing an anode in the sediment at the bottom of the water system and a cathode in the water layer above the sediment, and connecting the two electrodes through an external circuit. Early SMFCs were developed to be used as power sources in hard-to-reach deep water areas or remote areas. However, recently, it has attracted a lot of attention as a technology for biologically purifying pollutants through its own power supply. Furthermore, it is being developed as a means of monitoring the environmental condition of the installed area. Despite the importance of SMFC, no comprehensive review has yet been published to the Korean readers on the trends and prospects of SMFC research. Therefore, in this review paper, the mechanism of SMFC, their mechanism of removal of organic, inorganic, and heavy metals, and the current state of SMFC technology are discussed, and future prospects are presented.

Currently, gray hydrogen and blue hydrogen are widely recognized as renewable energy, but in reality, they are made from fossil fuels. The most important task to achieve the hydrogen-based society is the development of economic green hydrogen production technology. Microbial electrolysis cell (MEC) is a next-generation energy-producing wastewater treatment technology that treats renewable organic wastewater and simultaneously produces the ultimate green hydrogen. For hydrogen production in MFC, it is necessary to input electrical energy into MEC. However, that energy is all covered by the energy produced by the MEC. Therefore, hydrogen production in MEC can be defined as the ultimate green hydrogen. This review contains an in-depth summary and analysis of the principles and feasibility of MEC technology, the composition and shape of MEC, electrode materials, and practical application cases in various types of wastewaters. Furthermore, compatibility and scalability with other environmental systems were reviewed at the pilot scale. Based on this, the technical limitations of MEC were diagnosed and future research directions for the practical application of MEC technology were suggested.

Objectives:Cement Kiln Dust (CKD), a cement industrial by-product, was used in this study to improve the effectiveness of CO2 removal and increase the production of precipitate calcium carbonate (PCC) in the accelerated mineral carbonation process, differentiating injection flow rate of alkaline agent into the process. Further, CKD, slag, waste cement powder (WC), coal fly ash (CFA) which are mainly used for mineral carbonation, were also compared for their total CO2 removal capability by the year. Methods:The morphology and composition of CKD were analyzed using FE-SEM, EDS and XRD to evaluate its applicability to mineral carbonation, and CKD extract and 1N NaOH were added into the reactor with the flow rate range of 1.1 to 3.0 mL/min for longer reaction time. And DTA was carried out for purity analysis of PCC. Last, for annual CO2 removal potential evaluation, CKD, slag, WC and CFA was compared based on the result from this and previous researches. Results:Result showed that 1N NaOH injection at flow rate of 1.1, 2.0, 3.0 mL/min accelerated the CO2 removal by the 61.7, 77.2, 41.5% and 48.2, 52.2, 54.3 g of PCC was generated respectively. The annual amount of industrial by-product in Korea is 26,664,893 tons/year, 8,000,000 tons/year, 2,531,750~7,595,250 tons/year and 884,854 tons/year, respectively, in order of Slag, CFA, CKD, waste concrete fine powder (WC). Thus, the annual removal of CO2 could be estimated in order of CKD>Slag>CFA>WC. Conclusion:CKD is a fine powder form with a high specific surface area, high calcium content, and high alkalinity. Therefore, CKD is superior to waste concrete or slag in mineral carbonation in removing CO2 and generating PCC. Considering the annual amount of CO2 removal when applying industrial by-products to the CCUS process, CKD and slag are considered the most economical mineral carbonation materials.

Microbial fuel cell (MFC) technology is receiving a lot of attention recently as a promising technology for generating electricity by treating organic waste resources. Over the past 20 years, the MFC technology has made rapid progress: various research on system architectures, electrochemistry, materials, and microbiology has been conducted for developing practical ideas and fundamental principles. Recently, a lot of research on scaled-up systems for practical application is being conducted in the MFC field. In this review, materials, electrochemistry, system development and scale-up systems of MFCs studied so far are reviewed, and future prospects and directions of MFC technology are presented.

Due to accidents related to chemical substances at home and abroad, the effects of hazardous chemicals on the environment and interest in them are increasing. In order to prevent the occurrence of hazardous chemical accidents, it is first necessary to clarify institutional standards for hazardous chemicals. Among the daily life products in which hazardous chemicals are detected, textile products are in close contact with the human body for a very long time, and thus are closely related to human health. However, our society's interest in the health of chemical substances in textile products is still insignificant. Therefore, this paper examines the seriousness of hazardous chemical substances in textile products and the limitations of their management system, and considers institutional supplementary measures. Formaldehyde, arylamine, and dimethyl-fumarate, which are regulated as harmful substances in textile products, mainly cause skin diseases through skin contact, and may cause organ damage when absorbed into the body. In Korea, hazardous chemicals are regulated in advance through the KC system. However, this system regulates only some of the heavy metals that are eluted, and chemicals such as phenols and toluene are not subject to regulation. The issuance of the KC mark is poor, and there is a problem that there is no obligation to mark the certification mark if the product is not intended for under 14 years of age. Therefore, it is necessary to expand and strengthen the scope of the regulation. It is mandatory to re-inspect OEKO-TEX® STANDARD, the standard of multinational corporations, every three years. The KC system also needs to follow this. The post-safety management system used when harmful fiber products exceeding the regulatory standards were analyzed by dividing into a product accident investigation and a national recall system. In order to increase the recall recovery rate, it is necessary to strengthen the information collection system, improve business awareness, and classify the recall stage as supplementary measures. Companies need to provide highly reliable textile products to consumers by participating in the ZDHC and Higg Index, which are programs for reducing hazardous chemical substances in textiles.

This review comprehensively reviewed floating offshore wind power generation technology, which is being newly developed as a mid- to long-term plan for wind energy. From the perspective of investment permegawatt (MW), offshore wind power is still about 50 percent more expensive than land wind power. Nevertheless, many advanced countries began to investigate the data because they wondered why they were immersed in development and investment, and why offshore wind facilities installed on the beach and floating offshore wind installed in the middle of the sea, unlike the land wind we knew. We looked at the basic principles of offshore wind power generation and the technologies used in facilities, and looked at the advantages and disadvantages of offshore wind power generation compared to land wind power generation, and what differences between fixed offshore wind farms and floating offshore wind farms. It is investigated whether it is a realistic plan to verify residents’ opposition to the installation of offshore wind power facilities, the possibility of commercialization such as high operational management costs, and the feasibility of installing facilities for renewable energy 3020 as midto long-term goals. In addition, it compares foreign cases with offshore wind power development complexes in Korea, marine wind power generation complexes in operation, and high wind power in Scotland, the first floating offshore wind power in Ulsan, Korea, to overcome difficulties in installing facilities and suggest directions for domestic offshore wind power development. In addition, in Korea, where there are not many countries suitable for wind power generation unlike overseas, it was decided to investigate whether floating offshore wind power could be the answer as planned. The reason why the government is pushing for investment in renewable energy such as solar power and wind power is because energy sources from the sun are eco-friendly. However, the U.S. and Europe, which started the wind power project early, are having difficulty in handling the wings of wind power generators. The energy source looked at the contradictions caused by environmental pollution in the treatment of waste, although it was environmentally friendly, and investigated how waste was treated and utilized overseas. Compared to other countries that entered the offshore wind power business earlier, domestic power generation projects are in their infancy and should focus on developing technology and co-prosperity with neighboring residents rather than on excessive expansion.

Objective:Seawater has a potential for managing the intensive potable drinking water demand. The recentconventional desalinating technologies are environmentally unsustainable and energy intensive. Thus, in the quest to find an alternative to the traditional desalination technologies, microbial desalination cells (MDC) have come into limelight. MDCs are considered the promising technologies for treating wastewater while simultaneously producing electricity, which can be utilized for desalinating seawater along with production of some value added products. However, some technical limitations associated with the practical usage of MDCs are pH maintenance at the cathodic side, internal resistance along with membrane fouling and its durability. Methods:These challenges can be dealt by utilizing various integrated configurations. Results and Discussion:Based on the study, the conventional technologies require less operational and maintenance cost but also less environmentally sustainable in comparison to these integrated MDC configurations. Conclusion:This review summarizes the basic working principles of MDCs, its types and factors affecting its performance and also several other applications associated with MDCs. This review also highlights various integrated MDC configurations which can be utilized for reducing the limitations associated to the conventional MDC system.

Approximately 50% of the 2600 decommissioned mines in South Korea are implicated in toxic metal/metalloid releases. One of the problems experienced in orchards situated near abandoned mines is the transport of heavy metals including mercury (Hg) into the plants. Due to high levels of Hg observed in orchard soils, heavy metal remediation is needed. The stabilization process is one of the widely used techniques to immobilize heavy metals in contaminated soil and waste. In this study, two types of starfish, Asterias amurensis (ASF) and Asterina pectinifera (PSF), were considered as stabilizing materials for remediating Hg-contaminated soil. In addition to natural starfish, the Hg immobilization effectiveness of calcined forms (CASF and CPSF) was also evaluated comparatively. The effect of particle size reduction on Hg immobilization was assessed for the ASF treatment. Total dosages of less than 10 wt% of ASF and PSF and less than 5 wt% of CASF and CPSF were applied to the Hg contaminated soil. Following treatment and curing for 28 days, the effectiveness of the stabilization process was evaluated using 1N HCl extraction tests. Overall, the stabilization results showed a decrease in Hg leachability with increasing dosages of ASF, PSF, CASF and CPSF. Generally, ASF outperformed the PSF treatments and calcined forms (CASF, CPSF) were more effective than natural forms (ASF, PSF). A reduction of approximately 79% was attained in Hg leachability for the 10 wt% ASF treatments. The -#20 mesh materials were more effective on Hg immobilization than the -#10 mesh materials. The Hg immobilization effectiveness exhibited the following increasing order: PSF (-#10 mesh) < ASF (-#10 mesh) < CPSF (-#10 mesh) < ASF (-#20 mesh) < CASF (-#10 mesh). It was found that effective Hg immobilization was most probably associated with the existing sulfur content in the starfish. The results of scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) indicated that a HgS compound and pozzolanic reaction products were responsible for effective Hg immobilization.

Microbial electrocatalysis reckons on microbes as catalysts for reactions occurring at electrodes. Microbial fuel cells and microbial electrolysis cells are well-known in this context; both prefer the oxidation of organic and inorganic matter for producing electricity. Notably, the synthesis of high energy-density chemicals (fuels) or their precursors by microorganisms using bio-cathode to yield electrical energy is called Microbial Electrosynthesis (MES), giving an exceptionally appealing novel way for producing beneficial products from electricity and wastewater. This review accentuates the concept, importance and opportunities of MES, as an emerging discipline at the nexus of microbiology and electrochemistry. Production of organic compounds from MES is considered as an effective technique for the generation of various beneficial reduced end-products (like acetate and butyrate) as well as in reducing the load of CO2 from the atmosphere to mitigate the harmful effect of greenhouse gases in global warming. Although MES is still an emerging technology, this method is not thoroughly known. The authors have focused on MES, as it is the next transformative, viable alternative technology to decrease the repercussions of surplus carbon dioxide in the environment along with conserving energy.

In recent years, there has been a significant accumulation of waste in the environment, and it is expected that this accumulation may increase in the years to come. Waste disposal has massive effects on the environment and can cause serious environmental problems. Thus, the development of a waste treatment system is of major importance. Agro-industrial wastewater and waste residues are mainly rich in organic substances, lignocellulose, hemicellulose, lignin, and they have a relatively high amount of energy. As a result, an effective agro-waste treatment system has several benefits, including energy recovery and waste stabilization. To reduce the impact of the consumption of fossil energy sources on our planet, the exploitation of renewable sources has been relaunched. All over the world, efforts have been made to recover energy from agricultural waste, considering global energy security as the final goal. To attain this objective, several technologies and recovery methods have been developed in recent years. The microbial fuel cell (MFC) is one of them. This review describes the power generation using various types of agro-industrial wastewaters and agricultural residues utilizing MFC. It also highlights the techno-economics and lifecycle assessment of MFC, its commercialization, along with challenges.

Biological treatment systems face many challenges in winter to reduce the level of nitrogen due to low temperatures. The present work aimed to study an electrochemical treatment to investigate the effect of applying an electric voltage to wastewater to reduce the ammonium nitrogen and COD (chemical oxygen demand) in domestic wastewater. This was done by using an electrochemical process in which a platinum-coated titanium material was used as an anode and stainless steel was used as a cathode (25 cm2 electrode area/500 mL). Our results indicated that the removal of ammonium nitrogen (NH4+–N) and the lowering of COD was directly proportional to the amount of electric voltage applied between the electrodes. Our seven hour experiment showed that 97.6% of NH4+–N was removed at an electric voltage of 5 V, whereas only 68% was removed with 3 V, 20% with 1.2 V, and 10% with 0.6 V. Similarly, at 5 V, the removal of COD was around 97.5%. Over the seven hours of the experiment, the pH of wastewater increased from pH 7.12 to pH 8.15 when 5 V was applied to the wastewater. Therefore, electric voltage is effective in the oxidation of ammonium nitrogen and the reduction in COD in wastewater.

Paradigm shift to wireless power transfer provides opportunities for ultra-low-power devices to increase energy storage from electromagnetic (EM) sources. The notable gain occurs when EM sources deliver information as a meaningful signal with power transfer. Thus, energy harvesting (EH) is an active approach to obtain power from surrounding EM sources that transfer energy deliberately. This paper discusses energy efficiency (EE) trade-offs and EE maximization in simultaneous wireless power and information transfer (SWIPT) for wireless sensor networks (WSNs). The power splitting (PS) and time switching (TS) model for SWIPT are investigated in detail, where EE optimization is essential. This work formulates EE maximization problem as non-linear fractional programming and proposes a novel algorithm to solve the maximization problem using Lagrange dual decomposition. Numerical results reveal that the proposed algorithm maximizes EE in both PS and TS modes through noteworthy improvements.