계통유연자원을 활용한 분산에너지 계통접속 한계용량 증대 기술

박정민 조선대학교 기초과학연구원 2023 조선자연과학논문집 Vol.16 No.4

Due to changes in the distribution system and increased demand for renewable energy, interest in technology to increase the limit capacity of distributed energy grid connection using grid flexible resources is also increasing. Recently, the distribution system system is changing due to the increase in distributed power from renewable energy, and as a result, problems with the limited capacity of the distribution system, such as waiting for renewable energy to connect and increased overload, are occurring. According to the power generation facility status report provided by the Korea Power Exchange, of the total power generation capacity of 134,020 MW as of 2021, power generation capacity through new and renewable energy facilities is 24,855 MW, accounting for approximately 19%, and among them, power generation through solar power accounts for a total portion of the total. It was analyzed that the proportion of solar power generation facilities was high, accounting for 75%. In the future, the proportion of new and renewable energy power generation facilities is expected to increase, and accordingly, an efficient operation plan for the distribution system is needed. Advanced country-type NWAs that can integrate the operation and management of load characteristics for each line of the distribution system, power distribution, regional characteristics, and economic feasibility of distributed power in order to improve distribution network use efficiency without expanding distribution facilities due to the expansion of renewable energy. An integrated operating system is needed. In this study, in order to improve the efficiency of distribution network use without expanding distribution facilities due to the expansion of renewable energy, we developed a method that can integrate the operation and management of load characteristics for each line of the distribution system, power distribution, regional characteristics, and economic feasibility of distributed power. We want to develop an integrated operation system for NWAs similar to that of advanced countries.

「분산에너지 활성화 특별법(안)」에 대한 검토

권경선(Kyoung-Sun Kwon) 한국지방자치법학회 2023 지방자치법연구(地方自治法硏究) Vol.23 No.1

우리의 전력을 담당하고 있는 한국전력공사는 1982년에 설립된 이래 지난 40여년간 좋은 품질의 전기를 값싸고, 안정적으로 공급해왔다. 그런데 종래의 중앙집중식 전력시스템은 지금 여러 국면에서 더 이상 변화를 미룰 수 없는 도전에 직면하고 있다. 그 첫 번째 이유는 전통적인 중앙독점적 전력 공급체계로 인한 경제적, 사회적 비용이 증대되고 있기 때문이다. 두 번째 이유는 전력의 안정적 공급에 차질이 발생할 우려가 높기 때문이다. 세 번째 이유는 재생에너지 증대에 따른 전력계통의 불안정성이 증대하고 있기 때문이다. 마지막으로 2005년 교토의정서가 발효된 이후 탄소중립, 온실가스 감축이라는 전 세계적인 흐름 가운데 우리나라와 기업들 역시 압력을 받고 있는데, 이러한 온실가스 감축은 전통적 중앙공급 체계로는 달성하기 어렵기 때문이다. 그렇다면 에너지산업에 있어서 대내외적으로 위기를 맞이하고 있는 지금 우리는 이 위기를 어떻게 극복할 수 있을 것인가? 바로 지역에서 에너지를 생산하고, 지역에서 에너지를 소비하는 에너지 지산지소(地産地消)를 구축해가는 것이다. 우리의 에너지 체계는 에너지의 생산과 유통, 판매 등과 관련하여 중앙에서 통제하고 있다. 그런데 위에서 살펴보았듯이 중앙집중식 에너지 공급체제의 한계를 나타냄에 따라 우리 정부와 에너지 전문가들은 이제 분산에너지체제로의 전환을 위해 노력하고 있다. 먼저 분산에너지 개념을 명확히 할 필요가 있다. 분산에너지란 에너지의 사용지역 인근에서 생산・소비되는 에너지를 말하며, 분산에너지 자원이란 수요지 인근에서 에너지의 생산・저장, 잉여 전력의 해소 등에 기여할 수 있는 자원을 가리킨다. 분산형 전원이 주로 발전원을 지칭하는데 반하여, ‘분산에너지자원(distributed energy resources, DER)은 태양광 등의 분산형 전원뿐만 아니라 에너지저장장치 및 수요자원 거래시장 등을 통칭하여 이른다. 분산에너지의 장점으로 인하여 전세계적으로 분산에너지 자원을 확대하고, 활성화 하는 시도들이 이루어지고 있다. 우리나라 역시 종전의 중앙집중식 에너지체제의 한계가 여러 측면에서 부각됨에 따라 산업통상자원부는 2021년 6월 전력계통 안정화방안과 분산에너지 자원의 확대 및 거래시장 활성화 계획을 담은 “분산에너지 활성화 추진전략”을 수립・발표하였다. 그리고 국회에서도 2021년 7월 더불어민주당 김성환 의원이 「분산에너지 활성화 특별법안」을 제안하였고, 2021년 9월에 상정하였다. 이에 본 고에서는 다음과 같이 「분산에너지 활성화 특별법안」의 내용을 구체적으로 살펴보았다. 1) 분산에너지의 정의 및 범위, 2)분산에너지 활성화 기본계획 및 시행계획, 3)분산에너지사업에 대한 등록제도, 4)분산에너지 설비의 설치의무 부여(의무할당제), 5)배전망의 관리・ 감독, 6)전력계통영향평가, 7)분산에너지 특화지역 지정 및 활성화 지원사업, 8)지역별 차등요금제 및 분산편익보상제도의 도입의 주요 내용과 시사점을 살펴보았다. 우리는 이제 분산에너지 활성화 특별법(안)을 통하여 분산에너지체제로 가기 위한 첫 발을 내딛고 있다. 특별법이 제정되면 인하여 분산에너지 보급 확대를 통한 에너지 공급체계 전환으로 에너지 수급의 안정성이 제고되고, 에너지 신산업이 활성화되며, 또한 분산에너지에 기반한 편익을 지역 주민에게 분배하여 지방경제 활성화에도 기여할 것으로 전망된다. 그런데 본 법(안)에서 아쉬운 부분도 있다. 분산에너지 활성화 특별법(안)은 단지 “물리적, 공간적” 의미의 지역에서 에너지 공급과 수요의 균형을 이루는 것을 목표로 하는 것은 아니라고 생각한다. 진정한 의미의 에너지 지산지소(地産地消)를 위해서는 기초 지방자치단체와 광역 지방자치단체에서 에너지 공급과 소비에 대한 계획을 세우고 대책을 강구할 수 있어야 한다. 바로 “지역에너지 분권”이 그러한 분산에너지 활성화 특별법(안)의 궁극적인 방향이라고 생각한다. 그러나 본 법안은 아직 거기까지 나아가지 못하고 있다. 본 연구에서는 지역에너지 분권을 실현하기 위한 구체적인 방안을 제시하고자 하였다. Korea Electric Power Corporation, which is in charge of electricity, has been supplying high-quality electricity cheaply and stably for the past 40 years since its establishment in 1982. However, existing centralized power systems now face the challenge of no longer delaying changes at various stages. The first reason is that the economic and social costs of traditional central proprietary power supply systems are increasing. The second reason is that there is a high risk of disruptions in stable power supply. The third reason is that the instability of the power system is increasing due to the increase in renewable energy. Finally, since the Kyoto Protocol took effect in 2005, Korea and companies have also been under pressure amid the global trend of carbon neutrality and greenhouse gas reduction, which is difficult to achieve with the traditional central supply system. So, how can we overcome this crisis now that we are facing a crisis both internally and externally in the energy industry? It is to create branches in areas that produce energy and consume energy. Our energy systems are centrally controlled with respect to the production, distribution and sale of energy. However, as seen above, the Korean government and energy experts are currently striving to transition to a decentralized energy system, showing the limitations of the centralized energy supply system. First, it is necessary to clarify the concept of distributed energy. Distributed energy refers to energy produced and consumed near areas where energy is used, and distributed energy resources refer to resources that can contribute to the production and storage of energy and the resolution of surplus power near the demand site. Distributed power sources mainly refer to power sources, while distributed energy resources (DER) collectively refer to energy storage devices and demand resource trading markets as well as distributed power sources such as solar heat. Due to the advantages of distributed energy, attempts are being made to expand and activate distributed energy resources worldwide. In June 2021, the Ministry of Trade, Industry and Energy established and announced a “distributed energy revitalization promotion strategy” that includes measures to stabilize the power system, expand distributed energy resources, and revitalize the trading market. Rep. Kim Sung-hwan of the Democratic Party of Korea proposed a special law to revitalize distributed energy in July 2021 and proposed it in September 2021. Therefore, in this paper, the contents of the special law on the activation of distributed energy were examined in detail as follows. 1) The main contents and implications of the definition and scope of distributed energy, 2) Basic plan and implementation plan for revitalizing distributed energy, 3) Distributed energy business registration system, 4) Duty to install distributed energy facilities (mandatory quota system), 5)The main contents and implications of the management and supervision of the distribution network, 6) power system impact assessment, 7) distributed energy specialized area designation and revitalization support project, and 8) regional differential rate system and distributed benefit compensation system were examined.

지역 에너지 자립을 위한 분산전원의 효율적 운영방안

송유진 사단법인 인문사회과학기술융합학회 2019 예술인문사회융합멀티미디어논문지 Vol.9 No.3

In order to achieve regional energy independence, small and distributed power generation resources (e.g., solar, ESS, fuel cells, etc.) will be increased and energy conversion centered on local demand will be active. This will require a review of orientation and related technologies for regional energy conversion policies as the regional unit energy management system is expected to surge in the virtual power plant/microgrid environment. The power industry paradigm is being digitalized around renewable energy. While this shift to ENERGY - ICT convergence is accelerating, there will also be many changes in energy policies in the future. In particular, in terms of energy demand management, it is likely that a local, self-contained decentralization will be established, along with the activation of the new renewables and other distributed energy sources (DER), and virtual power plants in the form of micro-grid are to be built locally. The establishment and operation of regional energy self-reliance and institutions that can implement it can be promoted, and the sharing and consultation of cases related to renewable energy facilities in other regions can increase self-reliance along with the development of local energy industries. 지역 에너지 자립화를 위해서 소규모의 분산형 발전 자원(태양광, ESS, 연료전지 등)이 늘어나고 지역 수요 중심의 에너지 전환이 활발해질 것이다. 이에 따라 가상발전소/마이크로그리드 환경에서 지역 단위 에너지관리 시스템이 급증할 것으로 예상됨으로써 지역 에너지 전환 정책에 대한 방향성 및 관련 기술 검토가 요구된다. 본 논문에서는 지역 에너지 자립화를 위한 효율적 수요관리 방안을 도출하기 위한 일환으로서, 분산전원의 효율적 운영 방안을 제시한다. 분산전원의 수요관리를 통해 중앙 기관으로부터 발전된 전력을 일방향으로 송전받아 사용하는 것이 아닌 개개인이 스스로 전력을 생산하여 사용하거나 타인에게 판매할 수 있는 프로슈머 간 전력 거래가 가능하게 된다. 또한, 신재생에너지 정책에 따른 지역의 역할을 모색함으로써 주민이 참여하여 지역 에너지 자립을 할 수 있는 방안을 검토하고자 한다. 지역에너지 자립과 이를 구현할 수 있는 기관의 설립·운영을 추진하고, 타 지역의 신재생에너지 설비와 관련된 사례의 공유 및 협의를 통하여 지역 에너지산업의 육성과 함께 자립도를 높일 수 있다.

Consumer-Oriented Distributed Energy Policy for Korea: Based on a Case Study of Victoria, Australia

( Alan Dixon Brown ),정주희 ( Juhee Jeong ),변장섭 ( Jangseop Byeon ),나주몽 ( Na Ju Mong ) 국제지역학회 2024 국제지역연구 Vol.28 No.2

한국은 최근 에너지시스템의 분산화를 촉진하기 위해 분산에너지 활성화 특별법을 제정하였다. 그러나 이에 대한 규제와 정책은 공급자 측면에 초점을 맞추고 있으며, 분산에너지의 수요자인 소비자에 대한 관심은 부족하다. 따라서 본 연구는 소비자 관점에서 분산에너지 정책에 대한 보완점에 대한 시사점을 제시하고자 한다. 이를 위해 선도적으로 분산에너지시스템을 도입하여 운영하고 있는 호주 빅토리아의 사례를 통해 소비자 관련 문제들을 확인하였다. 해당 사례 연구를 바탕으로, 본 연구는 PRISMA 절차에 따라 소비자 관점에서 분산 에너지 시스템에 대한 국제 연구를 체계적으로 검토하였다. 최종적으로 선정된 문헌을 공동 검토한 후, 각 논문의 연구결과를 '정보', '제품 및 서비스 구매', '설치 및 연결', '운영 및 관리', '분쟁 해결', '규제 프레임워크'로 분류하였다. 그 결과로 다음과 같은 정책적 시사점을 도출하였다. 첫째, 고객이 합리적인 공급자를 선택할 수 있도록 공급자에 대한 정보와 선택옵션이 제공되어야 한다. 둘째, 분산에너지의 전력 계통 측면에서 에너지저장장치(ESS)의 설치 및 연결이 필요하다. 셋째, 분산에너지에 적합한 동적 및 차등적 요금제가 필요하다. 넷째, 분산에너지에서 소비자의 권리를 확보하기 위한 법적·제도적 장치가 마련되어야 한다. Korea recently enacted the “Special Act on the Promotion of Distributed Energy”, which sets out to develop a localized, environmentally friendly energy system. However, related regulations and policies pay little attention to distributed energy consumers. Therefore, this study sets out to derive implications for consumer-oriented distributed energy policies. First, a case study of consumer-related issues from Victoria, Australia, was provided. Second, based on the case study, a Systemic Literature Review of international research on distributed energy from the consumer's perspective was conducted. The following policy implications emerged: information and options should be provided for rational supplier selection by customers; it is necessary to install and connect energy storage systems in the power system aspect of distributed energy; there is a need for dynamic and differentiated tariffs suitable for distributed energy; legal and institutional mechanisms should be established to secure consumer rights in distributed energy.

한국의 지역순환경제형 분산에너지 활성화 연구: 일본 후쿠오카현의 지역신전력 사업을 중심으로

변장섭,정주희,나주몽,ALAN DIXON BROWN 한국도시행정학회 2024 도시 행정 학보 Vol.37 No.2

지난 2023년 6월 13일 「분산에너지 활성화 특별법」 이 제정・공포됨에 따라, 2024년 6월 14일부터는 재생에너지를 중심으로 한 소규모 발전시설들의 전력 직거래가 가능하게 되었고, 지역 단위의 분산에너지가 활성화될 수 있는 법・제도적 장치가 마련되었다. 그러나 아직 국내에서는 소규모 발전사업자들이 분산에너지 사업에 참여할 수 있는 명확한 비즈니스 모델이 정립되지 않고 있다. 반면 일본은1995년부터 전력 자유화가 시작되어, 2016년부터는 가정・상점을 위한 저압전력까지 확대되어 전면적인 전력 소매 자유화가 되었다. 특히 이 시점부터 시작된 지역신전력 사업은 자치단체가 직접 출자한 법인(또는 조합 등)을 통해 지역 내에서 재생에너지 중심 전력을 생산하고 지역 내의 주요 소비자에게 전력을 판매함으로써 자금과 일자리가 지역 내에서 순환하는 지역순환경제를 목표로 분산에너지가활성화되는 계기를 마련해 주었다. 본 연구는 이러한 일본의 지역신전력사업을 평가한 자료들을 온라인을 통해 수집하고 분석하여, 우리나라의 지역순환경제형 분산에너지를 활성화시키기 위한 시사점을제공한다. 즉 소규모 발전사업자들이 분산에너지 관련 사업을 원활히 진행하기 위해서는 자치단체나지역금융의 출자를 통한 안정적인 자금 공급이 필요하며, 지역 내의 확실한 수요처를 확보해야 할 것이다. 또한 안정적인 에너지원 확보와 더불어 지역 내에서 일자리를 창출시킬 수 있는 비즈니스 모델이 확보되어야 할 것이다. The 「Special Act on the Promotion of Distributed Energy」 was enacted and promulgated on June 13, 2023. Based on the Act, renewable energy-centered small-scale power facilities have been allowed to engage in direct electricity trading from June 14, 2024, enabling the activation of local distributed energy through legal and institutional mechanisms. However, no clear business model has been established in Korea for small-scale power producers to participate in distributed energy projects. In Japan, on the other hand, power liberalization began in 1995, expanding from 2016 to include low-voltage power for households and businesses, which resulted in full-scale retail power liberalization. In particular, the local new power projects initiated from this point onward have enabled the production of renewable energy-oriented power within the region through corporations (or cooperatives, etc.) directly invested by local governments. This has been a catalyst for the activation of distributed energy by aiming for a local circular economy where funds and jobs circulate within the region, through selling power to major consumers in the region. This study collects and analyzes data evaluating these Japanese regional new power projects through online sources, providing insights to domestically promote regional circular economy-type distributed energy. For small-scale power producers to smoothly pursue distributed energy-related projects, stable funding through investments from local governments or regional financial institutions is necessary, and securing definite demand sources within the region is crucial. Furthermore, it is necessary to develop a business model that can create jobs within the region.

연구논문 : 지방분권화 시대 대구광역시의 신재생에너지 보급 확대방안

최용호 ( Yuong Ho Choi ),조성덕 ( Sung Duk Cho ) 한국환경정책평가연구원 2004 환경정책연구 Vol.3 No.1

The purpose of this study is to propose a way to develop and disseminate the renewable energy technologies and industries in the local community. Fundamentally, the renewable energy is able to reduce environmental pollution and diminish a use of fossil-fuel energy in the local area. And it will lead to promoting regional sustainable energy in the future, as well as making contributions to local economic development. Above all, based on the environmental conservation project, including greening of the city and improving water quality, Daegu metropolitan city has launched a series of renewable energy projects, such as solar city programs and local energy plan. But, some problems still exist, due to the technological, economic and socio-political barriers. Thus, to encourage and disseminate a renewable energy in Daegu city, we need to examine a present condition on renewable energy and analyze constraint elements to prevent its distribution. Based on the results, we have to set the feasible strategy to develop and disseminate renewable energy in Daegu city and help it systematically integrate renewable energy technologies and industries into environmental economics and city planning. Ultimately, to achieve this purpose, we need to adopt the following policy measures: (1) establishment of a master plan for renewable energy; (2) interconnection between local development project and energy industry; (3) promotion of technological development; (4) inducement of and assistance to renewable energy industry; (5) fostering venture companies; (6) specializing Daegu`s public office by energy-specific education programs. In particular, local entities including local company, consumers, policy-makers and citizen`s groups have to pay attention to local energy plan for the regional sustainable energy future. These measures will lead to establishing an environmentally friendly and sustainable city.

A fast sampling algorithm for energy-angle distributions of bremsstrahlung photon for radiotherapy applications

Wasaye Muhammad Abdul,Yu Tao,Xie Jinsen,Chen Zhenping,Ni Zining 한국물리학회 2023 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.82 No.10

A fast sampling algorithm for energy-angle distributions of bremsstrahlung photon for radiotherapy purposes is presented. Efcient and accurate sampling methods have been developed based on the most accurate and reliable diferential cross-sections for sampling the energy-angle distributions of bremsstrahlung photons by incident electron of energy 1 MeV–20 MeV. Scaled energy-loss numerical diferential cross-sections produced by Seltzer and Berger are used to sample the photon energy. A new sampling method based on a double diferential cross-section of Koch and Motz has been developed which uses a simplifed expression to sample the bremsstrahlung photon angular distribution. The average efciency of sampling photon energy distribution algorithm is about 85% for electrons with kinetic energies 5 MeV–20 MeV and below to 75% for electrons of kinetic energies 1 MeV–5 MeV. Computation time comparisons have been evaluated with the previous algorithm to sample one photon energy. The inverse transform sampling procedure is implemented to sample the photon angular distribution; hence, every sampled value of the angular distribution is accepted. Therefore, the proposed algorithm is very fast and efcient for radiotherapy purposes. The sampling methods’ accuracy is checked by comparing the Monte Carlo sampled distributions with the theoretical expressions.

Performance of ZF Precoder in Downlink Massive MIMO with Non-Uniform User Distribution

Chuili Kong,Caijun Zhong,Zhaoyang Zhang 한국통신학회 2016 Journal of communications and networks Vol.18 No.5

In this paper, we investigate the achievable sum rateand energy efficiency of downlinkmassive multiple-inputmultiple-output antenna systems with zero-forcing precoding, by taking intoaccount the randomness of user locations. Specifically, we pro-pose two types of non-uniform user distributions, namely, center-intensive user distribution and edge-intensive user distribution. Based on these user distributions, we derive novel tight lower andupper bounds on the average sum rate. In addition, the impact ofuser distributions on the optimal number of users maximizing thesum rate is characterized. Moreover, by adopting a realistic powerconsumption model which accounts for the transmit power, circuitpower and signal processing power, the energy efficiency of the sys-tem is studied. In particular, closed-form solutions for the key sys-tem parameters, such as the number of antennas and the optimaltransmit signal-to-noise ratio maximizing the energy efficiency, areobtained. The findings of the paper suggest that user distributionhas a significant impact on the system performance: for instance,the highest average sum rate is achieved with the center-intensiveuser distribution, while the lowest average sum rate is obtainedwith the edge-intensive user distribution. Also, more users can beserved with the center-intensive user distribution.

Electron Energy Distribution for a Research Electron LINAC

Lim, Heuijin,Lee, Manwoo,Yi, Jungyu,Kang, Sang Koo,Kim, Me Young,Jeong, Dong Hyeok Korean Society of Medical Physics 2017 의학물리 Vol.28 No.2

The energy distribution was calculated for an electron beam from an electron linear accelerator developed for medical applications using computational methods. The depth dose data for monoenergetic electrons from 0.1 MeV to 8.0 MeV were calculated by the DOSXYZ/nrc code. The calculated data were used to generate the energy distribution from the measured depth dose data by numerical iterations. The measured data in a previous work and an in-house computer program were used for the generation of energy distribution. As results, the mean energy and most probable energy of the energy distribution were 5.7 MeV and 6.2 MeV, respectively. These two values agreed with those determined by the IAEA dosimetry protocol using the measured depth dose.

An Optimal Installation Strategy for Allocating Energy Storage Systems and Probabilistic-Based Distributed Generation in Active Distribution Networks

Tohid Sattarpour,Behrouz-Tousi 한국전기전자재료학회 2017 Transactions on Electrical and Electronic Material Vol.18 No.6

Recently, owing to increased interest in low-carbon energy supplies, renewable energy sources such as photovoltaics andwind turbines in distribution networks have received considerable attention for generating clean and unlimited energy. The presence of energy storage systems (ESSs) in the promising field of active distribution networks (ADNs) would havedirect impact on power system problems such as encountered in probabilistic distributed generation (DG) model studies. Hence, the optimal procedure is offered herein, in which the simultaneous placement of an ESS, photovoltaic-based DG, andwind turbine-based DG in an ADN is taken into account. The main goal of this paper is to maximize the net present valueof the loss reduction benefit by considering the price of electricity for each load state. The proposed framework consists ofa scenario tree method for covering the existing uncertainties in the distribution network’s load demand as well as DG. Thecollected results verify the considerable effect of concurrent installation of probabilistic DG models and an ESS in definingthe optimum site of DG and the ESS and they demonstrate that the optimum operation of an ESS in the ADN is consequentlyrelated to the highest value of the loss reduction benefit in long-term planning as well. The results obtained are encouraging.