New power generation technology options under the greenhouse gases mitigation scenario in China

Climate change has become a global issue. Almost all countries, including China, are now considering adopting policies and measures to reduce greenhouse gas (GHG) emissions. The power generation sector, as a key source of GHG emissions, will also have significant potential for GHG mitigation. One of the key options is to use new energy technologies with higher energy efficiencies and lower carbon emissions. In this article, we use an energy technology model, MESSAGE-China, to analyze the trend of key new power generation technologies and their contributions to GHG mitigation in China. We expect that the traditional renewable technologies, high-efficiency coal power generation and nuclear power will contribute substantially to GHG mitigation in the short term, and that solar power, biomass energy and carbon capture and storage (CCS) will become more important in the middle and long term. In the meantime, in order to fully bring the role of technology progress into play, China needs to enhance the transfer and absorption of international advanced technologies and independently strengthen her ability in research, demonstration and application of new power generation technologies.     

Current status of research on optimum sizing of stand-alone hybrid solar–wind power generation systems

Solar and wind energy systems are omnipresent, freely available, environmental friendly, and they are considered as promising power generating sources due to their availability and topological advantages for local power generations. Hybrid solar–wind energy systems, uses two renewable energy sources, allow improving the system efficiency and power reliability and reduce the energy storage requirements for stand-alone applications. The hybrid solar–wind systems are becoming popular in remote area power generation applications due to advancements in renewable energy technologies and substantial rise in prices of petroleum products. This paper is to review the current state of the simulation, optimization and control technologies for the stand-alone hybrid solar–wind energy systems with battery storage. It is found that continued research and development effort in this area is still needed for improving the systems’ performance, establishing techniques for accurately predicting their output and reliably integrating them with other renewable or conventional power generation sources.     

Review on combined wind power generation and energy storage systems

储能系统由于能够实现电能的时空平移,具有响应速度快,规模化等优点,是改善风电波动性,提高其并网能力的有效手段,构建风储联合发电系统成为目前研究重点.简单介绍了风电并网对电力系统的影响及不同类型电池储能技术的发展现状,给出了部分国内外风储联合发电系统的示范工程,并分析了平滑风电功率波动,跟踪计划出力曲线和削峰填谷3种主要运行方式,重点阐述了目前风储联合发电系统控制策略和储能容量配置研究现状,对进一步开展风储联合发电系统的研究进行了展望,指出经济性仍然是制约储能技术应用的关键问题之一,提高包含储能单元的风储联合发电系统的经济性是今后的研究重点.     

Determining optimal electricity technology mix with high level of wind power penetration

Notwithstanding its variability and limited controllability, wind power is expected to contribute strongly to electricity generation from renewable energy sources in the coming decades. Treating wind power as non-dispatchable by subtracting its output from the original load profile, results in a net load profile, which must be covered by conventional power generation. The screening curve methodology is a first approximation to find the optimal generation technology mix, based on relative cost levels. However, increased variability of the net load profile, due to wind power generation, strongly influences system operation. Therefore a static linear programming investment model is developed to determine the optimal technology mix. This alternative methodology shows a reduced capacity of inflexible generation after including operational constraints to properly account for net load variability. In order to illustrate this methodology, an example is set up, showing the sensitivity with respect to ramp rates of conventional generation, transmission interconnection and energy storage. The comparison of those different sources of system flexibility suggests that energy storage facilities better facilitate the integration of wind power generation.     

Financial analysis of utility scale photovoltaic plants with battery energy storage

Battery energy storage is a flexible and responsive form of storing electrical energy from Renewable generation. The need for energy storage mainly stems from the intermittent nature of solar and wind energy sources. System integrators are investigating ways to design plants that can provide more stable output power without compromising the financial performance that is vital for investors. Network operators on the other side set stringent requirements for the commissioning of new generation, including preferential terms for energy providers with a well-defined generation profile. The aim of this work is to highlight the market and technology drivers that impact the feasibility of battery energy storage in a Utility-scale solar PV project. A simulation tool combines a battery cycling and lifetime model with a solar generation profile and electricity market prices. The business cases of the present market conditions and a projected future scenario are analyzed.     

电力工业的储能时代

风电、太阳能发电等新能源的开发利用正迅速发展,由于新能源发电大都具有随机性、间歇性,因而将使电力工业进入储能时代。最近30年来,世界能源领域有3个变化:一是环境问题由区域性问题变成全球性问题;二是因化石能源顶峰论和枯竭论导致化石能源恐慌;三是化石能源价格暴涨。由此把全球能源利用推向第三次能源大转换,用新能源发电替代化石能源发电,并催生了智能电网。电力工业在100多年的历史中,前后经历了舞伴时代、电力需求侧管理时代,现在为了发展新能源和智能电网,电力工业将进入储能时代。中国在最近20年内,无论是在需求侧管理方面还是在需求响应方面的工作都优于工业发达国家,中国电力工业已进入了电力需求侧管理时代。大容量储能是新能源开发的"瓶颈",是智能电网的"瓶颈",要想加快新能源和智能电网的开发,就要把大容量储能放在战略位置上,抓好大容量储能技术的突破。现在技术比较成熟的储能设施是抽水蓄能电站,但是投资大、能量转换损耗大,不可能全靠它来解决大容量储能问题。主要问题还是技术不成熟和政策问题,应加大对大容量储能技术的研究开发力度,在新能源发电规划和智能电网规划中要有相应的大容量储能规划,同时要尽快理顺电价。     

Modeling,evaluation, and optimization of gas-power and energy supply scenarios

Recently, renewable energy sources such as wind power and photovoltaic (PV) are receiving a wide acceptance because they are inexhaustible and nonpolluting. Renewable energy sources are intermittent ones because of climate changes in wind speed and solar irradiance. Due to the continuous demand growth and the necessity for efficient and reliable electricity supply, there is a real need to increase the penetration of gas technologies in power grids. The Canadian government and stakeholders are looking for ways to increase the reliability and sustainability of power grid, and gas-power technologies may provide a solution. This paper explores the integration of gas and renewable generation technologies to provide a qualified, reliable, and environmentally friendly power system while satisfying regional electricity demands and reducing generation cost. Scenarios are evaluated using four key performance indicators (KPIs), economic, power quality, reliability, and environmental friendliness. Various scenarios outcomes are compared based on the defined performance indices. The proposed scenario analysis tool has three components, the geographic information system (GIS) for recording transmission and distribution lines and generation sites, the energy semantic network (ESN) knowledgebase to store information, and an algorithm created in Matlab/Simulink for evaluating scenarios. To interact with the scenario analysis tool, a graphical user interface (GUI) is used where users can define the desired geographic area, desired generation percentage via gas technology, and system parameters. To evaluate the effectiveness of the proposed method, the regional zone of the province of Ontario and Toronto are used as case studies.     

A comparative review on power conversion topologies and energy storage system for electric vehicles

Fossil fuel depletion and its adverse impact on global warming is a major driving force for a recent upsurge in the development of hybrid electric vehicles technologies. This paper is a conglomeration of the recent literature in the usages of an energy storage system and power conversion topologies in electric vehicles (EVs). An EV requires sources that have high power and energy density to decrease the charging time. Commonly used energy storage devices in EVs are fuel cells, batteries, ultracapacitors, flywheel, and photovoltaic arrays. The power output from energy storage sources is conditioned to match load characteristics with the source for maximum power delivery. A DC-DC converter topology performs this task by way of transforming voltage under the condition of power invariance. In addition, power electronics is also required to power DC/AC motors efficiently with precise control as these motors provide tractive efforts and acts as prime movers. This paper therefore brings out a critical review of the literature on EV's power conversion topologies and energy storage systems with challenges, opportunities and future directions by systematic classification of EVs and energy storage.     

Carbon capture and storage potential in coal-fired plant in Malaysia—A review

Secure, reliable and affordable energy supplies are necessary for sustainable economic growth, but increases in associated carbon dioxide (CO₂) emissions, and the associated risk of climate change are a cause of major concern. Experts have projected that the CO₂ emissions related to the energy sector will increase 130% by 2050 in the absence of new policies or supply constraints as a result of increased fossil fuel usage. To address this issue will require an energy technology revolution involving greater energy efficiency, increased renewable energies and nuclear power, and the near-decarbonisation of fossil fuel-based power generation. Nonetheless, fossil fuel usage is expected to continue to dominate global energy supply. The only technology available to mitigate greenhouse gas (GHG) emissions from large-scale fossil fuel usage is carbon capture and storage (CCS), an essential part of the portfolio of technologies that is needed to achieve deep global emission reductions. However, CCS technology faces numerous issues and challenges before it can be successfully deployed. With Malaysia has recently pledged a 40% carbon reduction by 2020 in the Copenhagen 2009 Climate Summit, CCS technology is seen as a viable option in order to achieve its target. Thus, this paper studies the potential and feasibility of coal-fired power plant with CCS technology in Malaysia which includes the choices of coal plants and types of capture technologies possible for implementation.     

Managing peak loads in energy grids: Comparative economic analysis

One of the key issues in modern energy technology is managing the imbalance between the generated power and the load, particularly during times of peak demand. The increasing use of renewable energy sources makes this problem even more acute. Various existing technologies, including stationary battery energy storage systems (BESS), can be employed to provide additional power during peak demand times. In the future, integration of on-board batteries of the growing fleet of electric vehicles (EV) and plug-in hybrid electric vehicles (PHEV) into the grid can provide power during peak demand hours (vehicle-to-grid, or V2G technology).This work provides cost estimates of managing peak energy demands using traditional technologies, such as maneuverable power plants, conventional hydroelectric, pumped storage plants and peaker generators, as well as BESS and V2G technologies. The derived estimates provide both per kWh and kW year of energy supplied to the grid. The analysis demonstrates that the use of battery storage is economically justified for short peak demand periods of <1 h. For longer durations, the most suitable technology remains the use of maneuverable steam gas power plants, gas turbine,reciprocating gas engine peaker generators, conventional hydroelectric, pumped storage plants.     

基于混沌自适应人工鱼群算法的含家庭储能配电网快速重构方法

针对分布式电源接入配电网具有波动性和随机性的特点,提出一种基于混沌自适应人工鱼群算法的含分布式电源配电网快速化重构方法。在风电、光伏和家用储能的数学模型和节点划分基础上,以电网网损、开关次数以及失电负荷成本最小为目标函数,建立基于多目标优化的含分布式电源配电网的优化重构模型。利用混沌自适应人工鱼群算法对模型进行求解,通过对鱼群的混沌初始化和自适应动态调整步长参数,提高了算法的全局搜索能力和收敛速度。根据电化学储能系统出力特性划分配电网网架重构的典型工作场景,通过含分布式电源的IEEE 33节点测试系统仿真实例验证了该文方法的有效性。仿真结果表明,与单独考虑电网网损成本相比,由该文方法得到的配电网优化重构成本降低了50%以上,优化重构时间均小于0.9 s,实现了含分布式电源配电网的快速自愈。     

Harmonizing nuclear and renewable energy: Case studies

Climate change is one of the grand global challenges facing the world community. With the global warming threat and the attendant public health risks caused by poor air quality and harmful fine particles, the two different energy sources—nuclear and renewables—may have found a common ground and thread to form an alliance to meet these grand global challenges. The latest advent of technologies enables load-follow flexibility of nuclear power, which has mainly provided baseload power, making nuclear energy an ideal partner for renewable energy, leveling the uncertainty and accommodating the unpredictability associated with renewables. The progress in small modular reactor (SMR) technology, which can be deployed to remote areas, can further facilitate the linking of the two energy resources. Some investigators have recently pioneered the ideas to inosculate these two energy resources with the aid of energy storage devices. This paper presents a series of case studies on meeting demand forecasts by coupling nuclear and renewable energy resources for various practical scenarios. The paper also proposes a paradigm shift in thinking in order to eliminate (or minimize to a certain extend) the need for energy storage devices in the combined energy production system by replacing the energy storage devices with some industrial facilities to directly utilize any excess power supplied by renewable energy. As an example, a desalination facility appended to the nuclear-renewable integrated system is shown to absorb surplus power from renewable energy to produce water, thereby satisfying the demand for both power and water in a typical small remote village. Case studies are also performed to extend the concept to include the effect of weather condition and seasonal variation in solar energy conditions. The promising role of disruptive emerging technologies in the nuclear-renewable combined system is also addressed.     

Design of a grid-connected PV system with hybrid energy storage

由于国内的储能技术起步较晚,分布式电源中应用单一储能介质很难满足系统运行要求.基于某公司的光伏储能并网系统示范项目,以具有快速响应特性的超级电容器和具有大容量储能特性的锂离子电池为混合储能系统,以储能控制器为控制核心统一协调控制,使电能以可控功率按需送入电网.该系统可有效提高储能系统的功率输出能力,优化储能系统的充放电过程,延长储能电池的使用寿命,具有良好的应用及推广价值.     

A current and future state of art development of hybrid energy system using wind and PV-solar: A review

The wind and solar energy are omnipresent, freely available, and environmental friendly. The wind energy systems may not be technically viable at all sites because of low wind speeds and being more unpredictable than solar energy. The combined utilization of these renewable energy sources are therefore becoming increasingly attractive and are being widely used as alternative of oil-produced energy. Economic aspects of these renewable energy technologies are sufficiently promising to include them for rising power generation capability in developing countries. A renewable hybrid energy system consists of two or more energy sources, a power conditioning equipment, a controller and an optional energy storage system. These hybrid energy systems are becoming popular in remote area power generation applications due to advancements in renewable energy technologies and substantial rise in prices of petroleum products. Research and development efforts in solar, wind, and other renewable energy technologies are required to continue for, improving their performance, establishing techniques for accurately predicting their output and reliably integrating them with other conventional generating sources. The aim of this paper is to review the current state of the design, operation and control requirement of the stand-alone PV solar–wind hybrid energy systems with conventional backup source i.e. diesel or grid. This Paper also highlights the future developments, which have the potential to increase the economic attractiveness of such systems and their acceptance by the user.     

电化学储能系统在整县制屋顶光伏中应用前景分析

屋顶分布式光伏作为可"自发自用"、"余电上网"的电源已得到广泛应用,随着国家政策的大力扶持,光伏发电技术和储能技术相辅相成逐渐成为主要产业.首先,从屋顶分布式光伏的扶持政策以及试点应用出发,然后根据当前屋顶分布式光伏发展亟待解决的问题分析,提出储能在适用于整县制屋顶光伏发展的核心技术:屋顶光伏和储能的场景生成和评价、屋...     

State of the art of the virtual utility: the smart distributed generation network

The world of energy has lately experienced a revolution, and new rules are being defined. The climate change produced by the greenhouse gases, the inefficiency of the energy system or the lack of power supply infrastructure in most of the poor countries, the liberalization of the energy market and the development of new technologies in the field of distributed generation (DG) are the key factors of this revolution. It seems clear that the solution at the moment is the DG. The advantage of DG is the energy generation close to the demand point. It means that DG can lower costs, reduce emissions, or expand the energy options of the consumers. DG may add redundancy that increases grid security even while powering emergency lighting or other critical systems and reduces power losses in the electricity distribution. After the development of the different DG and high efficiency technologies, such as co‐generation and tri‐generation, the next step in the DG world is the interconnection of different small distributed generation facilities which act together in a DG network as a large power plant controlled by a centralized energy management system (EMS). The main aim of the EMS is to reach the targets of low emissions and high efficiency. The EMS gives priority to renewable energy sources instead of the use of fossil fuels. This new concept of energy infrastructure is referred to as virtual utility (VU). The VU can be defined as a new model of energy infrastructure which consists of integrating different kind of distributed generation utilities in an energy (electricity and heat) generation network controlled by a central energy management system (EMS). The electricity production in the network is subordinated to the heat necessity of every user. The thermal energy is consumed on site; the electricity is generated and distributed in the entire network. The network is composed of one centralized control with the EMS and different clusters of distributed generation utilities and heat storage tanks. Each of these clusters is controlled by a local management station (LMS). Every LMS has information about the requirements (heat, cold and electricity) of the users connected to its cluster and the state of the utilities and water level of the storage tanks in its cluster. The EMS receives the information from the LMSs and sets the electricity input or output of every cluster in the network. With the information ordered by the EMS, the LMS set the run or stand‐by of the utilities of its cluster. The benefits of the VU are the optimization of the utilization yield of the whole network, the high reliability of the electricity production, the complete control of the network for achieving the main aim of the EMS, the high velocity for assuming quick changes in the demand of the system and high integration of renewable energy sources, plus the advantages of the DG. This paper indicates the state of the art of the VU concept, analyses the projects that are being developed in this field and considers the future of the VU concept. Copyright © 2004 John Wiley & Sons, Ltd.     

The Transformation of the Nuclear Power Industry

During the 1980s and early 1990s, the nuclear power generation industry in the US was viewed by the public as a dying industry owing mainly to concerns about the safety of the nuclear units, the storage of spent nuclear fuel, transportation of nuclear materials to central locations, and the general security of the nuclear facilities. Since then, the industry has transformed itself from one perceived as a dangerous, expensive technology to that of a reliable electrical power source. It is now viewed as a positive source of power from a global warming perspective. Aggressive industry initiatives to improve plant operation and maintenance have alleviated the public fear of nuclear technology. With the public unrest quieted and the cost of non-nuclear generation on the rise, the promise of nuclear power as a safe and reliable energy source may now be realized     

Recent advances in ammonia synthesis technologies: Toward future zero carbon emissions

As a carbon-free molecule, ammonia has gained great global interest in being considered a significant future candidate for the transition toward renewable energy. Numerous applications of ammonia as a fuel have been developed for energy generation, heavy transportation, and clean, distributed energy storage. There is a clear global target to achieve a sustainable economy and carbon neutrality. Therefore, most of the research's efforts are concentrated on generating cost-effective renewable energy on a large scale rather than fossil fuels. However, storage and transportation are still roadblocks for these technologies, for example, hydrogen technologies. Ammonia could be replaced as a viable fuel for a clean and sustainable future of global energy. More efforts from governments and scientists can lead to making ammonia a clean energy vector in most energy applications. In this review, ammonia synthesis was assessed, including conventional Haber–Bosch technology. Current hydrogen technologies as the key parameters for ammonia generation are also evaluated. The role of ammonia as a hydrogen-based fuel and generation roadmap are discussed for future utilization of energy mix. Further, ammonia generation processes are addressed in depth, including blue and green ammonia generation. A survey of ammonia synthesis catalytic materials was conducted and the role of catalyst materials in ammonia generation was compared, which showed that the Ru-based catalyst generated the maximum ammonia after 20 h of starting experiment. An end-use plan for using ammonia as a clean energy fuel in vehicles, marines, gas turbines as well as fuel cells, is briefly discussed to recognize the potential applications of ammonia use. The practical and future end-use vision of energy sources is proposed to achieve great benefits at low carbon emissions and costs. This review can provide prospective knowledge of large-scale aspects and environmental considerations of ammonia. Herein, we conclude that ammonia will become the “clean energy carrier link” that will achieve the global energy and economy sustainability targets.     

Prediction of global solar irradiance based on time series analysis: Application to solar thermal power plants energy production planning

Due to strong increase of solar power generation, the predictions of incoming solar energy are acquiring more importance. Photovoltaic and solar thermal are the main sources of electricity generation from solar energy. In the case of solar thermal energy plants with storage energy system, its management and operation need reliable predictions of solar irradiance with the same temporal resolution as the temporal capacity of the back-up system. These plants can work like a conventional power plant and compete in the energy stock market avoiding intermittence in electricity production.This work presents a comparisons of statistical models based on time series applied to predict half daily values of global solar irradiance with a temporal horizon of 3 days. Half daily values consist of accumulated hourly global solar irradiance from solar raise to solar noon and from noon until dawn for each day. The dataset of ground solar radiation used belongs to stations of Spanish National Weather Service (AEMet). The models tested are autoregressive, neural networks and fuzzy logic models. Due to the fact that half daily solar irradiance time series is non-stationary, it has been necessary to transform it to two new stationary variables (clearness index and lost component) which are used as input of the predictive models. Improvement in terms of RMSD of the models essayed is compared against the model based on persistence. The validation process shows that all models essayed improve persistence. The best approach to forecast half daily values of solar irradiance is neural network models with lost component as input, except Lerida station where models based on clearness index have less uncertainty because this magnitude has a linear behaviour and it is easier to simulate by models.