• 한국산림과학회지
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• 제111권1호
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• pp.177-185
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• 2022

이 연구의 목적은 산림바이오매스를 이용한 에너지 시설의 경제적 타당성을 검토한 것이다. 산림청 산림에너지자립마을 사업의 자료를 이용하여 에너지 시설의 운영 수지를 분석하였다. 에너지 시설은 열병합 발전기와 목재칩 보일러로 구성되며 목재칩을 연료로 사용한다. 목재칩은 목재펠릿보다 발열량이 낮지만 가격도 낮다. 시설 운영의 수입은 전기, 열, REC로 구성되며 추가로 화석연료 대체에 의한 탄소배출권을 고려하였다. 비용에는 연료비용과 고정비용이 포함되며, 초기 시설투자는 매몰비용으로 간주하였다. 가동률 55%, 목재칩 가격 95,000원/톤의 조건에서 에너지 시설의 연간 순수입은 양으로 나타났다. 시설 운영의 중요한 요소는 가동률과 연료비용이다. 두 요소를 조정하면서 시뮬레이션한 결과 가동률 50%, 목재칩 가격 100,000원/톤의 조건에서 연간순수입은 음으로 나타났다. 운영 수지를 개선하기 위해 가동률을 올리거나 연료 가격을 낮추는 노력이 필요하다. 탄소배출권을 판매한다면 시설 운영의 수익성을 개선한다. 또, 산림바이오매스의 에너지 이용을 촉진하기 위해 재생에너지로 공급한 열에 가격 보조를 할 필요가 있다.

• KIEAE Journal
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• 제10권1호
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• pp.33-44
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• 2010

These days, the use of alternative energy is recognized as one of countermeasures to rising oil prices and climate-change agreements. Especially, it is regarded as a main element to realize 'Low-Carbon Green Growth', one of the key policies of MB government. However, though alternative energy, renewable energy, is a main policy issue of the present administration, there are many problems to solve: the lack of recognition of its energy, the low level of its technology, its expert's shortage, and its limited application fields. Therefore, to stimulate the use of alternative energy in Korea and to change the recognition of this energy, it is needed to utilize it to urban street furniture that many people visit and use. In particular, if alternative energy is first applied to street furniture that needs energy for its management, the effect of publicity and energy saving will be so great. In this study, for the basic research to introduce and promote various alternative energy sources such as solar power, wind power, small hydro power, and human power, we analyzed the present condition of development of Korean and foreign street furniture items. Furthermore, we evaluated the level of development of these street furniture products and the design types of them and from these evaluations suggested the design direction that can solve problems in development and improve the possibility of application of these energy sources to these street furniture items. Through these analyses, this study aims to enhance the image of future environment-friendly city and make new index for the application of alternative energy.

• Journal of Power Electronics
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• 제15권5호
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• pp.1227-1234
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• 2015

The efficient electric power demand management in electric power supply industry is currently being changed by distributed generation. Meanwhile, small-scale distributed generation systems using renewable energy are being constructed worldwide. Several small-scale renewable distributed generation systems, which can supply electricity to the grid at peak load of the grid as per policy such as demand response programs, could help in the stability of the electric power demand management. In this case, the power quality of the small-scale renewable distributed generation system is more significant. Low prices of power semiconductors and multilevel inverters with high power quality have been recently investigated. However, the conventional multilevel inverter topology is unsuitable for the small-scale renewable distributed generation system, because the number of devices of such topology increases with increasing output voltage level. In this paper, a single-phase multilevel inverter based on H-bridge, with DC_Link divided by bi-directional switches, is proposed. The proposed topology has almost half the number of devices of the conventional multilevel inverter topology when these inverters have the same output voltage level. Double Fourier series solution is mainly used when comparing PWM output harmonic components of various inverter topologies. Harmonic components of the proposed multilevel inverter, which have been analyzed by double Fourier series, are compared with those of the conventional multilevel inverter. An inverter prototype is then developed to verify the validity of the theoretical analysis.

• Advances in Energy Research
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• 제5권1호
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• pp.57-64
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• 2017

Electricity is basic need for country development. But at the present time proper planning and policy is require at high pace for power generation network extension due to the increasing population growth rate. Present study aimed to analyze the present and future demand for electricity at household level in Province of Balochistan of Pakistan via simulation modeling. Data of year 2004-2005 was used as baseline data for electricity consumption to predict future demand of electricity at both rural and urban domestic level up to subsequent 30 years, with help of LEAP software. Basically three scenarios were created to run software. One scenario was Business-As-Usual and other two were green scenarios i.e., solar and wind energy scenarios. Results predicted that by using alternative energy sources, demand for electricity will be fulfill and will also reduce burden on non-renewable energy sources due to the greater potential for solar and wind energy present in Balochistan.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.313-320
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• 2009

Indonesian Ministry of Environment estimates that each year 170 cities and regencies in Indonesia produce 45,764,354.30 $m^3$ or approximately 11,441,091.08 ton of solid waste. Unfortunately, unsustainable management system has created a severe waste problem, hazardous to health and environment. This paper deals with the problem and offers some solutions. They are 3R (Reduce Reuse and Recycle), waste-to-energy concept and landfill gas (LFG) utilization. While 3R policy has been adopted by the government, the remaining two technologies are still dormant. Thus the paper provides a complete yet compact analysis of technology, economics, and environment aspect of waste-to-energy and LFG. Given the facts of waste production and management in Indonesia, the purpose is to encourage Government of Indonesia and other stake holders (including international community) to explore and exploit this potential. Potential of reducing waste negative externality while receiving extra revenue. Two bird with a stone.

• Fisheries and Aquatic Sciences
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• 제24권11호
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• pp.341-350
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• 2021

The energy production of offshore wind farms plays an important role in expanding renewable energy. However, the development of offshore wind farms faces many challenges due to its incompatibility with marine environments and its social acceptability among the local community. In this study, we reviewed the marine environmental impact assessment status of offshore wind farm development projects for 2012-2019 in South Korea. A total of nine projects were selected for this study, all of which experienced considerable conflict with local fisheries resources. To appropriately respond to the underlying challenges faced by offshore wind farm development and in order to better support decision-making for future impact assessment, our findings identified: i) a need for adequate preliminary investigation and technical examination of fisheries resources; ii) a need to assess and estimate the impact of underwater noise, vibration, and electromagnetic waves on fisheries resources during wind farm construction and operation; and iii) a need for a bottom-up approach that allows for communication with local stakeholders and policy-makers to guarantee the local acceptability of the development.

• 한국태양광발전학회지
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• 제6권1호
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• pp.21-34
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• 2020

Sri Lanka has strongly understood the importance of mitigation of climate change and various measures have been taken. To tackle the climate change, after ratifying Paris Agreement, Sri Lanka has pledged to reduce her greenhouse gas emission in the energy sector by 20% (16% unconditional and 4% conditional) by 2030 based on the BAU scenario. Simultaneously, the government introduced its new energy policy and strategies in 2019 with a vision of achieving carbon neutrality by 2050. This paper survey related key government documents, policies, reports, and academic articles to investigate opportunities for the private sector to invest large scale solar power deployment (10 MW or above) and to get support from climate finance under article 6 of the Paris Agreement. It has found, growing concern on the environment, energy security issues and increase import expenses for fossil fuels are the main influencing factors to move renewable sources. Further, government investment and FDI both have gradually decreased in the energy sector. Therefore, an alternative financing mechanism is needed. Although the private sector allowed investing in the energy sector since 1996 with the introduction of IPP (Independent Power Producers), it could not make considerable progress on involving large scale solar utility projects. This has revealed government policy is not aligning with the long term generation plan of the electricity sector. The study has also found, it needs more strategic road map, coordination with different institutions, monitoring system to enhance large scale solar contribution.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권9호
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• pp.3075-3093
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• 2014

In this paper, we consider an advanced wireless user, called primary-secondary user (PSU) who is capable of harvesting renewable energy and connecting to both the primary network and cognitive radio networks simultaneously. Recently, energy harvesting has received a great deal of attention from the research community and is a promising approach for maintaining long lifetime of users. On the other hand, the cognitive radio function allows the wireless user to access other primary networks in an opportunistic manner as secondary users in order to receive more throughput in the current time slot. Subsequently, in the paper we propose the channel access policy for a PSU with consideration of the energy harvesting, based on a Partially Observable Markov decision process (POMDP) in which the optimal action from the action set will be selected to maximize expected long-term throughput. The simulation results show that the proposed POMDP-based channel access scheme improves the throughput of PSU, but it requires more computations to make an action decision regarding channel access.

• Current Photovoltaic Research
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• 제10권2호
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• pp.62-71
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• 2022

The Global RE100 campaign is a one of the voluntary campaign, but it has a lot of influence on domestic companies that have not yet joined the Global RE100. Accordingly, the Korean government introduced the Korean RE100 (K-RE100) system to prepare an institutional mechanism for domestic companies to respond to RE100. However, in Korea, due to the high LCOE of renewable energy and institutional limitations of the power transaction system, there is a limit for companies to implement RE100 in various ways. Therefore, in this study, the implementation cost of RE100 for green tariff, REC purchase, third-party PPA, direct(or corporate) PPA, and self-generation was compared and analyzed to derive the order of implementation with the net present value (NPV) of costs incurred over 20 years. As a result, self-construction was analyzed as the most economical method, but the implementation through the green tariff seemed to be the most realistic implementation method so far. However, considering the gradually falling LCOE, third-party PPA and direct PPA could be secured competitiveness against green tariff in 2025 and 2026. Then it could allow the companies to have various portfolios for implementation of RE100.

• 한국수소및신에너지학회논문집
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• 제35권3호
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• pp.269-279
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• 2024

Saudi Arabia is transitioning from its traditional oil-dependent economy to become a leader in the hydrogen industry. This paper explores the kingdom's strategic investments in hydrogen production and infrastructure as key components of its energy diversification and sustainability efforts. The focus is on enhancing green hydrogen production to meet domestic needs and strengthen its position in the global market. The urgency of diversifying energy sources is emphasized, with projects like the NEOM Green Hydrogen Project illustrating Saudi Arabia's commitment to renewable energy integration. These initiatives are positioned to centralize Saudi Arabia in the global shift toward sustainable energy, signaling a significant pivot in its economic and environmental policies.