ABSTRACT In the restructured power system under deregulation, proper pricing of electricity has emerged as a key issue. The cost of transmission and distribution activities needs to be allocated to the users of these networks. Among others, power losses are one of the costs to be allocated. The main difficulty faced in allocating losses is the nonlinearity between the losses and delivered power which complicates the impact of each user on network losses. The purpose of this article is to review the various loss allocation schemes as applicable to the distribution systems. These schemes have been compared considering a simple radial distribution system. Since cogeneration and distributed generation (DG) plants often generate power for on-site consumption, and a fraction of the output is for export to the grid, developers of cogeneration and DG with substantial on-site consumption can realize significant savings in transmission and distribution losses. Thus, the schemes discussed herein can help a cogeneration or DG developer estimate such distributed-loss cost savings.
ABSTRACT In this article, energy and exergy analysis of an ongoing, 44-MW, heat-matched, bagasse-based cogeneration plant of Ugar Sugar Works Ltd (USWL), located in Belgaum, India is presented. In the analysis, exergy methods with more conventional energy analysis are employed to assess the thermodynamic efficiencies and losses. The performance of the plant was estimated, and a detailed break up of energy and exergy losses for the considered plant has been presented. The fuel energy savings ratio of the cogeneration plant is estimated in comparison with separate generation plants. The plant performs with energy and exergetic efficiency of 65% and 25%, respectively. Energy losses mainly occurred in the boiler exhaust and condenser, where 35 MW and 27 MW is lost to environment, respectively. The percentage ratio of the exergy destruction to total exergy destruction was found to be maximum in the boiler system (71%) of fuel exergy input or 45% of the physical exergy input. The total exergy destruction in the plant's components is 58% of physical energy input. The plant's fuel energy savings ratio is 8.2%. Because of its inherent combustion irresistibility, the boiler is the major contributor to the plant's overall inefficiency. The inefficiencies in bagasse-fired boilers can be reduced to some extent by increasing the pre-heated, excess air supply and generating steam at possible high pressure and temperature. In terms of technology development, only cogeneration plants with exergetic efficiency close to that of overall efficiency of the conventional power plant be suggested
The sugar industry is attaining new dimensions in the fast chang-ing world. It is poised to play a much higher and wider role. Per-formance and productivity of the sugar industry plays a vital role inattaining new dimensions. To be productive, sugar companies have towork as sugar complexes, producing sugar, ethanol, power and otherbyproducts. Cogeneration of power in the sugar industry is an importantsource of revenue. The conditions in India demand sugar industries togenerate and sell the electricity. This has created a new surge of interestamong the sugar mills for surplus power generation during the crushingseason using bagasse. This is possible and achievable only if the steamgeneration in the plant is increased and also the power and steam re-quirements of the plant are reduced. The study is aimed to relate variousparameters of bagasse, cane crushed to steam generation. Single factoranalysis of variance (ANOVA) is used to establish the significance ofeach parameter. Regression analysis is carried to establish the relationbetween parameters. The article arrives at a multiple regression equationrelating the steam generated as a function of its associated parametersviz. cane crushed, bagasse % of cane, moisture % of bagasse, pol % ofbagasse.
Full realization of the potential of converting landfill gas (LFG)and farm manure to biogas and LFG could, together, significantlysupplement our national supply of natural gas. Another advantage ofthese sources is that they tend to be located near end users and maybe considered analogous in some respects to distributed generationbecause the gas they provide does not have to be transported longdistances. There are many ways to generate electricity and few waysto produce biogas. Unfortunately, factors such as constantly changingnatural gas prices, the relatively small size of individual projects froma financing prospective, the fact that historic technology for convertinganimal waste did not always perform properly and the “comfort level”of gas sellers in remaining with existing natural gas supplies have seri-ously hindered the development of these sources. Federal and state taxbenefits and incentive programs (such as the federal stimulus) offer thepromise of increased development of these important domestic energyresources and available technology provides the possibility of realizingthese domestic energy resources and contributing to gas price stabilityand domestic energy security.
Energy efficiency can play a major role in the long-term viability ofany building. The technology and practices are readily available to makea difference in both new and existing buildings. In most cases, the moreresources one consumes, the greater the opportunity for savings. If sav-ings are reinvested in new efficiency measures, the compounding effectover time can be dramatic. Further management practices can reduceoperations and maintenance (O&M) costs, ensuring that efficiency gainsare enhanced and maintained. Ultimately, the business becomes morecompetitive. “Buying Down the Cost of Renewable Energy” encouragesa successful business plan that not only is good for the environment butmakes sound financial sense. In fact, a practical and proven method isto start a revolving pool of funds with the savings from no-cost andlow-cost energy conservation measures. This pool is reinvested everyyear in increasingly more sophisticated efficiency projects. Eventually,the revolving savings pool becomes big enough to be the source of eq-uity investment; which facilitates the financing of larger projects suchas combined heat and power (CHP) and alternative energy plants. Suchmoney pool grows the same way a wisely managed investment portfoliodoes. The underlying discipline supports three key energy managementelements: (a) fiscal responsibility and financial management, (b) organi-zational learning and (c) plant modernization or innovation.
Many federal energy-savings performance contract (ESPC) projectshave more opportunities than the traditional demand-side energy con-servation measures (ECMs). Federal organizations can incorporate moreadvanced technologies, like renewable energy sources, into their projectbundles when the energy services company (ESCO) takes advantageof creative financing, incentives and rebates available. This article willcover the following aspects of solutions development for renewable andcombined heating and power (CHP) projects for the federal government.Included will be a discussion of more advanced ECMs available to aparticular location.1. Solutions development process overview2. Samples of conventional ECM projects3. Samples of advanced ECM technologies4. CHP projects5. Renewable projects
Like many energy projects, the potential energy savings from theinstallation of a combined heat and power (CHP) system is based on thesystem’s specifications and the building’s previous energy consumptionpatterns. Although this is a generally accepted way to analyze the feasi-bility of the system, actual energy savings will often depend on the waythe system is ultimately engineered, installed and operated. This articlewill show the importance for budgeting nominal resources to conductindependent post installation commissioning, metering and data logging(especially on smaller projects). It will show how using independentmetering and monitoring can help optimize CHP operations, identifyoperational problems and limit unwanted thermal dumping.This article will show how actual data and utility metering datacollected after the installation of a 150-kW CHP in a New York City(NYC) multi-family building were used to optimize system performanceof radiator fans, circulating pumps and existing domestic hot water(DHW) equipment. The article will also show how logger data wereused to identify problems with system components that may limit thepotential savings to the client. Finally, it will show how post installationmonitoring helped establish the optimal seasonal operating hours forthe system that maximized thermal energy consumption and minimizedunwanted heat dumping.
The recent trends in electrical power distribution system operationand management are aimed at improving system conditions in order torender good service to the customer. Reforms in the distribution sectorhave given major scope for employment of distributed generation (DG)resources which will boost system performance. This article proposesa heuristic technique for allocation of multiple distribution generationsources in a distribution system. The allocation is determined based onoverall improvement in network performance parameters like reductionin system losses, improvement in voltage stability, improvement in volt-age profile. The hybrid of Genetic Algorithm with the proposed NetworkPerformance Enhancement Index (NPEI) along with the heuristic rulesfacilitates determination of feasible location for insertion of DG sources.A priority list is prepared with decreasing values of NPEI so that thedesigner can select most feasible locations. The developed approach istested with different test systems to ascertain its effectiveness.
Many countries in Europe promote cogeneration as a way to meetenergy needs in residential and commercial buildings. They do this tosave primary energy and reduce CO2 emissions. This article presents anenergy and economic analysis approach for cogeneration plants hostedby such buildings. The plants use gas-fired internal combustion enginesas prime movers. Technical criteria to characterize annual operation forcogeneration systems with seasonally and daily variable heat demandare defined. The focus is on determining the total engine size or outputby considering different operational strategies. The methodology is il-lustrated by applying it to a cogeneration plant that meets domestichot water and heating demand in a residential complex in Spain. Theresulting graphical analysis allows one to compare various operationalstrategies.
Parker Hannifin Corporation (“Parker”), in conjunction with Con-stellation Energy, investigated the possibility of developing a solar in-stallation at its New Britain (Connecticut) manufacturing facility. Parkereventually developed the project after carefully considering all of therelevant factors, which included not only the electricity price ($/kWh)comparison of solar with traditional brown power, but also future pricecurves, history of energy prices, and displacement cost with peak vs.blended price considerations.
(2007). Editorial Guidelines for Submittals. Cogeneration & Distributed Generation Journal: Vol. 22, No. 2, pp. 73-75.
The importance of distributed generation (DG) devices in theenergy solution mix is well recognized. Recent advances in high tem-perature fuel cell technology have resulted in their acceptance as reliablesources of power in the DG marketplace. High temperature fuel cellshave electrical efficiencies that exceed conventional power generationtechnologies in the same size range. The emissions signature of a fuelcell is favorable when compared to other DG technologies. In additionto the high electrical efficiency and low generation of criteria pollutants,the high temperature exhaust gases from these fuel cells can be used todrive a variety of combined heat and power (CHP) devices that maynot be accessible to other DG technologies.The unique electrical power and thermal output characteristics ofhigh temperature fuel cells make them ideal candidates across manyapplications. The high exhaust temperature provides the end-user withthe flexibility of generating steam, hot water or driving an indirect-firedabsorption chiller. This article will describe CHP characteristics of hightemperature fuel cells and some of the applications where they haveunique benefits: wastewater treatment plants, hospitals and data centers.
The Atlantic County Utilities Authority (ACUA) has two divi-sions, Solid Waste and Wastewater, and holds as its mission to be anenvironmental leader responsible for enhancing the quality of life for itsresidents through the protection of waters and lands from pollution byproviding responsible waste management services.ACUA’s mission is accomplished via the use of new technologies,innovations and employee ideas. These technologies include the use ofsustainable landfill technologies and waste diversion strategies. Waste-water, the most energy intensive of the two divisions, now derives themajority of its energy from on-site renewable sources. ACUA was alsothe first New Jersey organization to join the Chicago Climate Exchange(CCX). CCX is the world’s first and North America’s only legally bind-ing, voluntary greenhouse gas (GHG) emission registry, reduction andtrading system.Additionally, ACUA is developing several projects. At Wastewater,two beneficial reuse projects are underway: a Category I in Smithville, NJand a Category IV for Marina Energy in Atlantic City, NJ. Both projectsare anticipated to be operational by 2010 and process a combined 155million gallons of water per year. At the Environmental Park, there aretwo exciting projects anticipated for development in 2009: a compressednatural gas (CNG) station and a landfill solar project.
To minimize power losses, it is important to determine the locationand size of local generators to be placed in unbalanced power distribu-tion systems. Because of some inherent features of unbalanced distribu-tion systems, such as radial structure, large number of nodes, and awide range of X/R ratios, the conventional techniques developed forthe transmission systems generally fail to determine optimum size andlocation for distributed generation (DG). This article presents a simplemethod for investigating the problem of contemporaneously choosingthe best location and capacity of DG in three-phase unbalanced radialdistribution systems (URDS) for power loss minimization and to im-prove the voltage profile of the system. The best DG location is deter-mined by using voltage index analysis, and capacity of DG is computedby a variational technique algorithm according to the available standardcapacity of DG. This article presents the results of simulations for 25-busand IEEE 37-bus unbalanced radial distribution system.
Stakeholders promoting landfill gas (LFG) energy projects are iden-tifying new funding incentives to implement LFG energy (LFGE) proj-ects. This article focuses on how landfills are participating in voluntarycarbon and renewable energy markets, and presents case studies fromaward-winning projects that utilize these funding mechanisms.Landfills participate in the voluntary carbon markets using one oftwo main mechanisms: on an exchange or through an over-the-counter(OTC) transaction. An exchange, such as the Chicago Climate Exchange(CCX), is likely the most well known mechanism. At present, CCX has35 registered landfill methane offset project providers in the United States[1]. As of April 2008, landfill methane projects comprised approximately9 percent of all the carbon credits issued by CCX. OTC transactions areprivate between the seller, buyer, and/or broker involved in the transac-tion. Despite their private nature, the volume of OTC traded emissions hassubstantially grown in recent years according to research from EcosystemMarketplace [2]. Recent data from Point Carbon indicate that 132 U.S.landfills have either made a transaction in the carbon market, or are in theprocess of developing, producing, certifying, or verifying their emissionsreductions to prepare for an OTC transaction or exchange on the CCX [3].In addition to carbon finance, LFGE projects generating electricityare also selling renewable energy certificates (RECs). These RECs arethen purchased by companies wishing to reduce their environmentalfootprint or used by utilities to comply with various renewable portfoliostandards.
