Life-cycle analysis of renewable energy systems

An imlementation of life-cycle analysis (LCA) for energy systems is presented and applied to two renewable energy systems (wind turbines and building-integrated photovoltaic modules) and compared with coal plants.     

基于信息物理模型的可再生能源电网能量平衡控制

分布式电源从属于不同运营部门,相互之间缺乏有效的信息交换,难以进行集中控制。文章针对可再生能源电网中由于新能源占比较高,易出现出力波动或出力不足,难以保障供能可靠性等问题,提出一种基于信息物理融合的可再生能源电网分布式能量控制模型。首先,为进一步提高可再生能源电网能量平衡控制能力,建立了可再生能源电网信息物理模型;然后,考虑可再生能源波动性对系统的干扰,建立一种自适应滑模观测器对可再生能源电网的扰动进行估计;最后,提出一种基于可再生能源电网的分布式协同控制器,并基于李雅普诺夫稳定性理论验证了该控制器的收敛性。仿真结果表明,文章所提出的控制方法可以提高可再生能源电网的能源利用率,增强系统的鲁棒性。     

Distributed load control of autonomous renewable energy systems

Autonomous renewable energy systems such as wind, solar, and micro-hydro require control methods to maintain stability, due to the real time variation of input energy and load, while maximizing the use of renewable energy. This paper describes the application of load control using a novel frequency and voltage-sensing device. The device uses a low cost microcontroller to monitor the system frequency and voltage. Load switching is carried out based on this information. Software was developed for frequency and voltage measurements and tested on a 18 kW, single phase, 50 Hz, micro-hydro system. A fuzzy control system was then developed which makes intelligent load switching decisions using inputs from the measurement algorithms coupled with expert knowledge expressed in the form of control rules. This load control system was then tested on the same micro-hydro system and on a site powered by a 60 kW, 3 phase, 50 Hz wind turbine only     

Profit-based conventional resource scheduling with renewable energy penetration

Technological breakthroughs in renewable energy technologies (RETs) enabled them to attain grid parity thereby making them potential contenders for existing conventional resources. To examine the market participation of RETs, this paper formulates a scheduling problem accommodating energy market participation of wind- and solar-independent power producers (IPPs) treating both conventional and RETs as identical entities. Furthermore, constraints pertaining to penetration and curtailments of RETs are restructured. Additionally, an appropriate objective function for profit incurred by conventional resource IPPs through reserve market participation as a function of renewable energy curtailment is also proposed. The proposed concept is simulated with a test system comprising 10 conventional generation units in conjunction with solar photovoltaic (SPV) and wind energy generators (WEG). The simulation results indicate that renewable energy integration and its curtailment limits influence the market participation or scheduling strategies of conventional resources in both energy and reserve markets. Furthermore, load and reliability parameters are also affected.     

Effect of wind energy system performance on optimal renewable energy model-an analysis

The Optimal Renewable Energy Model (OREM) has been developed to determine the optimum level of renewable energy sources utilisation in India for the year 2020–21. The model aims at minimising costefficiency ratio and determines the optimum allocation of different renewable energy sources for various end-uses. The extent of social acceptance level, potential limit, demand and reliability will decide the renewable energy distribution pattern and are hence used as constraints in the model. In this paper, the performance and reliability of wind energy system and its effects on OREM model has been analysed. The demonstration windfarm (4 MW) which is situated in Muppandal, a village in the southern part of India, has been selected for the study. The windfarm has 20 wind turbine machines of 200 KW capacity. The average technical availability, real availability and capacity factor have been analysed from 1991 to 1995 and they are found to be 94.1%, 76.4% and 25.5% respectively. The reliability factor of wind energy system is found to be 0.5 at 10,000 hours. The OREM model is analysed considering the above said factors for wind energy system, solar energy system and biomass energy systems. The model selects wind energy for pumping end-use to an extent of 0.3153×10¹⁵ KJ.     

可再生能源交流孤网转并网运行中的电压控制策略

柔性直流远距离输送有仅通过直流送出模式和交直流混联送出模式。两种送出模式下,系统的运行点存在较大差异,直接切换会对电网产生较大冲击。文章首先分析了两种送出模式下系统的调压控制特点,指出并网点电压幅值偏差是切换过程的关键点,设计了以可再生能源集群并网点电压偏差最小为主目标,换流站综合无功裕度最大为次目标的柔性切换策略。最后,基于某柔直电网可再生能源送端规划系统进行仿真,验证了所提策略的有效性。     

热泵技术与可再生能源的开发利用

目前,可再生能源和热泵技术受到广泛的重视.通过对可再生能源与热泵关系的分析以及对热泵低温热能采集方式的论述表明,可再生能源是热泵低温热源的主要来源,而热泵是可再生能源低温热利用最有效的方式,热泵技术的利用极大地拓展了可再生能源的利用范围.     

Multi-objective optimal design of hybrid renewable energy systems using PSO-simulation based approach

Recently, the increasing energy demand has caused dramatic consumption of fossil fuels and unavoidable raising energy prices. Moreover, environmental effect of fossil fuel led to the need of using renewable energy (RE) to meet the rising energy demand. Unpredictability and the high cost of the renewable energy technologies are the main challenges of renewable energy usage. In this context, the integration of renewable energy sources to meet the energy demand of a given area is a promising scenario to overcome the RE challenges. In this study, a novel approach is proposed for optimal design of hybrid renewable energy systems (HRES) including various generators and storage devices. The ε-constraint method has been applied to minimize simultaneously the total cost of the system, unmet load, and fuel emission. A particle swarm optimization (PSO)-simulation based approach has been used to tackle the multi-objective optimization problem. The proposed approach has been tested on a case study of an HRES system that includes wind turbine, photovoltaic (PV) panels, diesel generator, batteries, fuel cell (FC), electrolyzer and hydrogen tank. Finally, a sensitivity analysis study is performed to study the sensibility of different parameters to the developed model.     

农村可再生能源与可持续发展

文章论述了可再生能源的结构及其在我国农村的发展,指出农村可再生能源的建设是一项综合的系统工程,需要政府,企业,农户的积极投入,才能达到能源,经济和环境的协调发展,才能推动“生态家园富民计划”的实施完成。     

发展可再生能源对浙江省节能减排的意义

分析了浙江省可再生能源资源条件和发展现状,提出了发展可再生能源是浙江省优化能源结构、降低能耗强度、保护生态环境、实现低碳经济发展的重要保障措施。     

欧盟的可再生能源促进政策对我们的启示

在环境问题的严峻挑战下,欧盟将可再生能源发展确立为关键的能源战略之一。欧盟在坚持固定电价制的同时确立可再生能源发电总量目标,在推进电力市场化改革的基础上强化对可再生电力的支持,并通过建立有效的化石燃料财税制度为可再生能源发展提供更广阔的空间。     

循环经济框架下的可再生能源发展回顾与思考

在国家倡导大力发展循环经济的形势下,回顾了国内外可再生能源产业现状,展望可再生能源产业发展的前景,剖析了可再生能源产业发展中的问题,提出了建设性的意见。     

意大利的节能和可再生能源激励机制

新能源与可再生能源产业是具有环境效益的弱势产业,在市场化过程中面临着诸多的障碍和问题,政府支持是新能源与可再生能源市场培育的原动力。不论是发达国家还是发展中国家,新能源与可再生能源的发展离不开政府的支持,如投融资、税收、补贴、市场渗透等一系列的优惠政策。文章介绍了意大利在节能和可再生能源方面的激励政策。     

广东可再生能源利用及发展研究

阐述了广东利用和发展可再生能源的必要性,分析了广东利用和发展可再生能源的有利条件,提出了广东可再生能源发展的重点及对策。     

Long-term optimization based on PSO of a grid-connected renewable energy/battery/hydrogen hybrid system

This paper presents and evaluates three energy management systems (EMSs) based on Particle Swarm Optimization (PSO) for long-term operation optimization of a grid-connected hybrid system. It is composed of wind turbine (WT) and photovoltaic (PV) panels as primary energy sources, and hydrogen system (fuel cell –FC–, electrolyzer and hydrogen storage tank) and battery as energy storage system (ESS). The EMSs are responsible for making the hybrid system produce the demanded power, deciding on the energy dispatch among the ESS devices. The first PSO-based EMS tries to minimize the ESS utilization costs, the second one to maximize the ESS efficiency, and the third one to optimize the lifetime of the ESS devices. Long-term simulations of 25 years (expected lifetime of the hybrid system) are shown in order to demonstrate the right performance of the three EMSs and their differences. The simulations show that: 1) each EMS outperforms the others in the designed target; and 2) the third EMS is considered the best EMS, because it needs the least ESS devices, and presents the lowest total acquisition cost of hybrid system, whereas the rest of parameters are similar to the best values obtained by the other EMSs.     

沿海地区可再生能源开发利用结构优化研究

针对我国目前能源开发利用可持续性及环境友好性差的问题,首先系统地分析了能源开发利用优化影响因素,在此基础上以经济效益、二氧化碳排放量、能源开发比例的综合效益最大为目标函数,从能源属性、经济、技术、环境和安全等方面考虑建立约束条件,构建了沿海地区可再生能源开发利用结构优化的多目标规划模型。以大连为例,对其沿海可再生能源结构进行优化,得到该地区目标年内的最优能源开发利用量,对模型进行了参数敏感性分析。研究成果可为可再生能源开发利用结构规划与政策制定提供参考。     

Medium term market perspectives,goal prices and competitiveness of renewable resources in the Italian energy system

Using a multiperiodal LP model (MARKAL) the authors assessed the likely potential of solar thermal and biogas systems under various circumstances. The study covered the period 1980–2005, in five segments of five years. It focused only on the subsystem of the energy end-uses which can be substituted for by solar and biogas technologies. In this paper we show the main results of the study regarding the competitiveness of the single solar and biogas technologies in different scenarios and their sensitivity to incentives and prices, together with the essential technical data regarding demand and supply technologies which produced those results. The analysis performed of the potential penetration of renewable technologies into the Italian energy system shows that their contribution will remain very marginal if the price of conventional energy carriers remains constant in constant money. However, the objective of removing with renewable technologies 1.5 per cent of the total Italian energy consumption appears to be realistic in the short-medium term.     

A unified REC market and composite RPO scheme for promotion of renewable energy in India

In India, uniform price was assigned to renewable energy certificate (REC) irrespective of renewable energy (RE) type, technology, and location. Moreover REC price bands are higher than existing preferential tariff. There are distinct renewable purchase obligations (RPOs) specified for various RE types, whereas there is lack of efficient tools to check RPO compliance. Because of these reasons, REC market stabilisation is getting delayed. This paper proposes a method using plant performance multiplier to convert non-solar and solar REC to single equivalent REC with competitive REC pricing, which can be traded on unified REC market. The method combines solar and non-solar RPOs into a single composite RPO, to make RPO compliance and its checking simple and efficient. A sample illustration of the proposed method is given. The benefits offered by the proposed method in REC pricing, REC trading and RPO compliance are discussed. A comparative economic analysis of present and proposed method is reported.     

可再生能源发展与就业潜力分析

根据全球可再生能源的发展形势,结合我国国情,分析了可再生能源发展及其对劳动力市场产生的影响.据预计可再生能源产业将为中国提供近百万个就业机会.从业人员素质通常需要具备设计、建筑、经济等方面的综合素质,然而具体需求会因城乡差别而不同.通常城市内的研发、设计和制造人员需要具备多学科的综合素质.而对于广大农村地区,可再生能源领域的从业人员主要以运行、维护等方面技能为主.为了实现国家的规划目标,人力资源的培训非常重要.     

英国可再生能源政策及启示

介绍了美国政府支持新能源、可再生能源发展及高耗能企业调控的做法、对策和取得的成效,并谈了体会和建议。