Photovoltaic projects for decentralized power supply in India: A financial evaluation

The present study concentrates on photovoltaic (PV) projects for providing decentralized power supply in remote locations in India. Results of a techno-economic evaluation are presented. Some PV projects in the capacity range 1–110 kW_p, that have either been implemented or are under implementation, have been considered. An analysis of the capital cost of the PV projects and sub-systems has been undertaken. Levelized unit cost of electricity (LUCE) has been estimated for eighteen select locations situated in different geographical regions of the country. The LUCE is found to vary in the range of Rs. 28.31–59.16/kW h (US$ 0.65–1.35/k Wh) for PV projects in the capacity range 1–25 kW_p. In view of high unit cost of electricity from PV projects, need for financial incentives has been examined from the perspective of users. A sensitivity analysis has also been undertaken.     

Photovoltaic power for telecommunications

Photovoltaic equipment may be an attractive power source for many kinds of communication equipment in the next five years. The first applications will be found in remote parts of the U.S. and in new systems installed overseas in areas remote from electric distribution grids. By the end of the 1980s, the equipment may compare favorably with grid electricity in some regions. This paper will discuss the kinds of improvements in equipment performance and manufacturing techniques which may lead to photovoltaic systems capable of competing in the communications industry, and estimate the cost of power which could be obtained if such improvements are achieved. It will review some of the problems of system design which must be confronted in constructing systems capable of meeting realistic demand patterns, and outline a technique for optimizing the size of components.     

Remote area power supply in Nigeria: the prospects of solar energy

This paper analyses power supply options for remote areas of Nigeria. Three systems were examined namely solar powered systems, conventional diesel generator plant and connection to the national grid. The analysis has shown that solar (photovoltaic) systems are the most economically viable, offering the least energy cost per annum. Photovoltaic power systems also provide a virtually maintenance free operation since they have no moving parts.     

Solid oxide fuel cell systems for distributed power generation and cogeneration

Solid oxide fuel cell (SOFC) is a promising technology for decentralized power generation and cogeneration. This technology has several advantages: the high electric efficiency, which can be theoretically improved through integration in power cycles; the low emissions; and the possibility of using a large variety of gaseous fuels.     

Optimal interface based on power electronics in distributed generation systems for fuel cells

A hybrid system comprising a fuel cell stack and a battery bank was developed, built and tested in this research work. This hybrid system was built to supply both DC and AC outputs. The voltage levels set on electrical interconnection points are achieved with several power conditioning stages controlled by Pulse Width Modulation (PWM). The main advantage of this system is its excellence as a test bench, since it allows testing system performance at different voltage-restricted interconnecting points. Besides, power electronics are observed to play an essential role in distributed generation systems. The applications of the developed hybrid system extend from Auxiliary Power Units (APU) in vehicles (cars, buses or trains) to Uninterruptible Power Systems (UPS) in hospitals, nursing homes, hotels, office buildings or schools.     

Miniaturization of spacecraft electrical power systems with solar-hydrogen power supply system

The concept of solar-hydrogen systems for spacecraft, orbital stations, lunar and Martian bases is currently receiving a new impetus. The supply of solar energy to energy receivers aboard space vehicles is limited. The number of everyday tasks and energy-intensive experiments on board space objects is growing with the development of astronautics. To perform energy-intensive work and experiments, energy consumption exceeds the incoming solar fluxes. The modern solar-hydrogen system ensures the reception, conversion and accumulation of excess incoming energy in the form of chemical energy - hydrogen. Cryogenics makes it possible to miniaturize the solar-hydrogen system. The safety of the cryogenic solar-hydrogen energy system is ensured by hydrogen concentration and leakage sensors.The article proposes a comprehensive solution for miniaturization of Power Conversion Unit (PCU) of Energy Power System (EPS) of spacecrafts (SC), which consists in a joint solution of four key problems of miniaturization of power devices: energy, structural, design and technological, system. Miniaturization of the solar-hydrogen energy system (SHES) is achieved by installing onboard hydrogen and oxygen microcryogenic refrigerators, as well as hydrogen and oxygen cryogenic tanks, water tank, electrolyzer and hydrogen fuel cells (FC). The accumulation of chemical hydrogen energy on board the orbiting spacecraft ensures reliable operation when entering the shadow. Storage of hydrogen in cryogenic form significantly reduces the volume required. A cryocooler based on the Stirling cycle provides the process of liquefying hydrogen after the electrolysis of distilled water. In addition, cryogenic temperatures of 20.2 K can be used to thermostat precision instruments placed on board the spacecraft, For example, to ensure the operation of the SQUID. A 3D - model of a voltage stabilization module (VSM), on the basis of which EEC can be produced with different output power and redundancy depth. We give an example of a complete structural scheme of the EEC, which allows implementing all the fulfillment of all the tasks, assigned to the EEC of the PCU SC.     

SmartGrid: Future networks for New Zealand power systems incorporating distributed generation

The concept of intelligent electricity grids, which primarily involves the integration of new information and communication technologies with power transmission lines and distribution cables, is being actively explored in the European Union and the United States. Both developments share common technological developmental goals but also differ distinctly towards the role of distributed generation for their future electrical energy security. This paper looks at options that could find relevance to New Zealand (NZ), in the context of its aspiration of achieving 90% renewable energy electricity generation portfolio by 2025. It also identifies developments in technical standardization and industry investments that facilitate a pathway towards an intelligent or smart grid development for NZ. Some areas where policy can support research in NZ being a “fast adapter” to future grid development are also listed.This paper will help policy makers quickly review developments surrounding SmartGrid and also identify its potential to support NZ Energy Strategy in the electricity infrastructure. This paper will also help researchers and power system stakeholders for identifying international standardization, projects and potential partners in the area of future grid technologies.     

Fuel cell based power systems to supply power to Telecom Stations

Hydrogen-Photovoltaic (H2-PV) hybrid systems may represent a valid solution to foster the use of renewable sources to power off-grid Radio Base Stations (RBSs) for telecom applications. The use of Polymer Electrolyte Membrane (PEM) Fuel Cells (FCs) would in fact allow for having higher efficiency and lower consumption of primary fossil sources. Within that context, a demonstration project has been funded in the FCH-JU European project named “FCpoweredRBS: Demonstration Project for Power Supply to Telecom Stations through FC technology”, which was kicked-off in January 2012. Activities of that project are described in this paper, including system design, the definition of a 72 h benchmark and measurements of system performances under specifically developed benchmark cycles.     

太阳能与风能发电在通信电源系统中的综合应用

介绍了太阳能发电与风力发电相结合在边远通信基站电源系统中的应用设计,针对通信系统的电源特点和要求,引入了主备控制方式的太阳能充电控制技术以及常规的高频整流方式的风能充电控制技术,两种发电方式组成的互为补充的供电方式,可大大降低单纯采用太阳能供电的电源系统成本,并进一步提高系统供电的安全性.     

Fuel-cell powered uninterruptible power supply systems: Design considerations

A 1-kVA fuel cell powered, line-interactive uninterruptible power supply (UPS) system that employs modular (fuel cell and power converter) blocks is introduced. Two commercially available proton-exchange membrane fuel cell (25–39 V, 500 W) modules together with suitable dc–dc and dc–ac power electronic converter modules are employed. A supercapacitor module is also used to compensate for the instantaneous power fluctuations and to overcome the slow dynamics of the fuel processor (reformers). Further energy stored in the supercapacitor is also utilized to handle a momentary overload such as 200% for a short duration. Due to the absence of batteries, the system satisfies the demand for an environmentally clean source of energy. A complete design that defines the amount of hydrogen storage required for a power outage of 1 h, and the sizing of the supercapacitors for transient load demand is presented for a 1-kVA UPS.     

Optimization of distributed hybrid power systems employing multiple fuel-cell vehicles

This paper investigates the benefits of distributed hybrid power systems employing multiple fuel-cell vehicles. In earlier work, our optimization of hybrid power systems showed that a single fuel cell acting as backup power to guarantee energy sustainability operates for less than 3% of the time but incurs more than 16% of the system costs. Therefore, the system cost could be reduced when applying a fuel-cell vehicle to dynamically support twelve power stations. Here, we extend this idea by employing multiple fuel-cell vehicles to support more power stations. We develop a power management strategy and optimize the management parameters by the genetic algorithm. The results show a reduction of more than 21% by applying multiple fuel-cell vehicles in the distributed systems. Experiments also confirm the feasibility of using multiple fuel-cell vehicles. Based on the results, the proposed systems are deemed effective for reducing system costs while maintaining system sustainability.     

论燃气轮机热电冷联产分布式电源系统

本文论述了燃气轮机热电冷联产分布式电源的系统装置、工作性能、优势及国内外发展现状 ;并从燃料成本、系统能效等方面分析了发展这种电源的经济性 ;建议我省在引进LNG之后 ,应当建设燃气轮机热电冷分布式电源的示范工程。     

Revival by automation of induction generator for distributed power systems, in Romanian academic research

The paper approaches the half-century history and the main research results of the academic staff and researchers from “Politehnica” University of Timisoara (Universitatea “Politehnica” Timisoara—UPT) and their collaboration with the academic, research and production environment concerning the use of induction machine as power supply in microhydro plants and windmills in particular; from among these collaborators we mention: The Romanian Academy—Timisoara Branch, The Institute for Automation IPA—Timisoara Branch, The Research and Modernization Institute for Energetics ICEMENERG Bucharest, The National Institute for Heat Engines INMT Bucharest, The Machine Construction Works UCMR—Resita, “Electroputere” Works—Craiova and “Electromotor” Works—Timisoara.The paper aims at presenting the original research results at UPT against the background of general research from all over the world focused on revival the induction generator by automation.     

Energy storage in remote area power supply (RAPS) systems

Preliminary cost analyses indicate that hybrid RAPS systems are more economically attractive as a means to provide electricity to remote villages than are alternatives such as 24 h diesel generation. A hybrid remote area power supply (RAPS) system is being deployed to provide 24 h electricity to villages in the Amazon region of Peru. The RAPS system consists of modules designed to provide 150 kWh per day of utility grade ac electricity over a 24 h period. Each module contains a diesel generator, battery bank using heavy-duty 2 V VRLA gelled electrolyte batteries, a battery charger, a photovoltaic array and an inverter. Despite early difficulties, the system in the first village has now commenced operation and the promise of RAPS schemes as a means for providing sustainable remote electrification appears to be bright.     

Demand side management for remote area power supply systems incorporating solar irradiance model

This paper presents a technique for generating the daily electricity load profile for remote areas in the Middle East from first principles, using diversified demand. The generated load profile includes the energy required to run a small desalination unit to provide the necessary freshwater. Demand side management (DSM) is used in this study to smooth out the daily peaks and fill valleys in the load curve to make the most efficient use of energy resources. Finally, the load profile is compared with real data for six houses collected from Safri area in the Sultanate of Oman. These data may be used as the basis to obtain load profiles of other remote areas of the Middle East since the weather and social factors are similar. The modified hourly variation factor based on weather and economic and social factors of the Middle East is obtained.A solar irradiance model is incorporated in the system to utilise the solar energy available in the Middle East region.     

Analysis of installed capacity and operation strategy for distributed combined heating and power systems

分布式热电联产系统是一种临近用户的先进能源系统,系统构型、装机容量和运行策略的选择对系统节能性、环保性和经济性有重要影响。本研究以某办公大楼为对象,根据其全年实时运行数据,分析了其热电负荷特征;同时,为该办公楼构建了分别以微燃机和内燃机为动力单元的两种不同CHP系统构型方案,建立了相应的变工况能量平衡模型。进一步探讨了系统在以热定电与以电定热、变工况运行与额定运行、有储热与无储热、24 h连续运行与早起晚停等不同运行策略下动力机组装机容量对该办公楼经济性、节能性和环保性的影响规律。同时运用多目标评价指标来对系统不同装机容量和运行策略下的收益综合评估,并引入了混沌粒子群优化算法来找到系统最大的综合收益,结果表明,该办公楼应用CHP系统后全年的经济性、节能性和环保性较传统的单一功能模式分别提高了22.85%、17.45%、25.06%。