Showing papers on "Base load power plant published in 2005"

A new approach to quantify reserve demand in systems with significant installed wind capacity

Abstract: With wind power capacities increasing in many electricity systems across the world, operators are faced with new problems related to the uncertain nature of wind power. Foremost of these is the quantification and provision of system reserve. In this paper a new methodology is presented which quantifies the reserve needed on a system taking into account the uncertain nature of the wind power. Generator outage rates and load and wind power forecasts are taken into consideration when quantifying the amount of reserve needed. The reliability of the system is used as an objective measure to determine the effect of increasing wind power penetration. The methodology is applied to a model of the all Ireland electricity system, and results show that as wind power capacity increases, the system must increase the amount of reserve carried or face a measurable decrease in reliability.

Impact of hourly wind power variations on the system operation in the Nordic countries

Abstract: The variations of wind power production will increase the flexibility needed in the system when significant amounts of load are covered by wind power When studying the incremental effects that varying wind power production imposes on the power system, it is important to study the system as a whole: only the net imbalances have to be balanced by the system Large geographical spreading of wind power will reduce variability, increase predictability and decrease the occasions with near zero or peak output The goal of this work was to estimate the increase in hourly load-following reserve requirements based on real wind power production and synchronous hourly load data in the four Nordic countries The result is an increasing effect on reserve requirements with increasing wind power penetration At a 10% penetration level (wind power production of gross demand) this is estimated as 1·5%–4% of installed wind capacity, taking into account that load variations are more predictable than wind power variations Copyright © 2004 John Wiley & Sons, Ltd

Wind plant integration [wind power plants]

Abstract: This paper discusses the key issues that confront power system planners and operators when integrating wind power plants into the electric power system. A key question is how the variations in wind plant outputs affect the operation of the power system on a daily basis and what the associated costs are. These costs are lower than initially expected by some utility engineers. The main reason for this is that wind tends to behave more like negative load than traditional firm-block generation, and the power system has been designed to handle significant load variations on a routine basis. This paper summarizes the key results of wind integration studies conducted to date and provides insights from individual studies. The studies present simulations of system operations that employ well-established production-costing and unit-commitment computational tools.

Power control methods and apparatus for variable loads

Abstract: A switching power supply is modified to mitigate potentially adverse effects of near zero loads on power delivery. In one example, a processor-controlled dummy load is coupled to the power supply output in addition to an actual load. The dummy load is controlled so that at least some minimal load is presented to the power supply when the actual load is drawing low or near zero power. In another example, the feedback loop of the switching power supply is modified to mitigate the effects of a potential overvoltage condition in a bias supply from which the switch controller of the power supply draws power, which condition may occur at low or near zero load power. A lighting system may include a switching power supply thusly modified to provide power to a variable load that includes one or more LED-based lighting apparatus.

Implications of on-site distributed generation for commercial/industrial facilities

Abstract: Next-generation distributed generation (DG) is poised to become a key element in our energy future. Recognizing the increased need for a higher reliability energy system and a cleaner environment, This work presents a technique that helps to identify the impact of grid-connected DG on the reliability of on-site electric power. This analysis shows the optimal DG mix at various facility outage costs with and without an emission restriction. The impact of varying the grid reliability and the capital costs of DG units on the decision to invest in backup power is discussed. The break-even costs of microturbines are also estimated at various facility outage costs and microturbine forced outage levels.

Oxyfuel combustion for coal-fired power generation with CO2 capture—Opportunities and challenges

Abstract: Publisher Summary This chapter illustrates that the increased carbon dioxide level in the atmosphere is the dominating contributor to increased global warming. Carbon dioxide is emitted to the atmosphere through combustion of fossil fuels in power plants, automotive engines, for industrial use and for heating purposes. The world is currently depending on the use of fossil fuels for its energy supply, and will continue to be so for a long time yet to come, due to the abundant sources of in particular bituminous coal and lignite. Small-scale renewable electricity production is available on the market today, but the cost of avoiding CO2 emissions through renewable is at present very high. It discusses oxyfuel recycle combustion is a highly interesting option for lignite-based power generation with CO2 capture, due to the possibility to use advanced steam technology, reduce the boiler size and cost and to design a zero-emission power plant. This technology, also poses engineering challenges in the areas of combustion and heat transfer, boiler design, boiler materials, energy-efficient oxygen production, and flue gas processing. The overall challenge is to design a robust plant that has a sufficiently low total cost of electricity so that it is interesting to build, but it must also have a sufficiently low variable cost of electricity so that it will be put in operation as a base load plant once it is built.

Making connections [wind generation facilities]

Abstract: Large-scale wind generation facilities have become a very visible component of the interconnected power grid in many options of the United States. Only a decade ago, wind generation facilities were viewed by most power engineers as a novelty, and by simple engineering judgement, it could be safely concluded that the effects of these unique but smaller facilities on system reliability would be negligible. Now, with individual wind generation facilities approaching the output rating of conventional power plants, a deeper understanding of their potential impacts on the interaction with the bulk electric power system is needed.

The future of wind forecasting and utility operations

Abstract: To run the power system most efficiently and effectively, we must focus our attention on the system as a whole rather than on individual components - and this is true regardless of whether or not the system includes wind generation. As larger amounts of wind energy are added to our power systems, we must certainly be aware of the impacts of its variability on the system, but we must also keep in mind that our power systems are already designed to deal with substantial amounts of uncertainty and variability. By making proper use of wind forecasting and integrating it into our control rooms and our systems, we can facilitate the cost-effective use of wind energy as a mainstream component of the energy system.

Impact of large scale wind power on power system stability

Abstract: The amount of wind power constantly increased during recent years requiring detailed analysis about the impact of wind power on system security and system operation. Therefore several wind impact studies have been carried out recently in different countries. The findings of these studies are usually related to a superposition of different aspects of wind power, such as the fluctuating nature, distributed location of wind farms, generator technologies, generator control etc. and predict required network reinforcements, additional reserve requirements, etc. This paper is focusing on transient stability issues and analyses the impact of various aspects like generator technology, connection points, distributed generation etc. separately for getting a thorough understanding about the impact of these aspects on transient stability.

Emissions and Energy Efficiency Assessment of Baseload Wind Energy Systems

Abstract: The combination of wind energy generation and energy storage can produce a source of electricity that is functionally equivalent to a baseload coal or nuclear power plant. A model was developed to assess the technical and environmental performance of baseload wind energy systems using compressed air energy storage. The analysis examined several systems that could be operated in the midwestern United States under a variety of operating conditions. The systems can produce substantially more energy than is required from fossil or other primary sources to construct and operate them. By operation at a capacity factor of 80%, each evaluated system achieves an effective primary energy efficiency of at least five times greater than the most efficient fossil combustion technology, with greenhouse gas emission rates less than 20% of the least emitting fossil technology currently available. Life-cycle emission rates of NOX and SO2 are also significantly lower than fossil-based systems.

System and method for controlling effective wind farm power output

Abstract: A method for controlling variability in power output of a wind farm supplying power to a grid includes monitoring a power output level of the wind farm. The monitored power output level is compared to a target power output level. A command is issued to increase or decrease electrical power consumption by an electrolyzer system electrically coupled to the wind farm to maintain a net power output level by the wind farm based upon the comparison.

Method and apparatus for providing economic analysis of power generation and distribution

Abstract: An economic dispatch program optimally allocates load demand specifying real power and reactive power to be generated by a power plant among various power generators in a manner so that each of the power generators are operated within its optimal operating space as defined by a reactive capability curve. Allocating a power demand with consideration of the reactive capability curves of the power generators results in optimal generation of real power and reactive power as specified by the load demand. Alternatively, the economic dispatch program allocates load demand specifying real power and reactive power to be delivered by a power grid among various power plants wherein one or more of the various power plants have capacity limits exhibited by reactive capability curves.

System and method for power control in wind turbines

Abstract: A system and method for power control in wind turbines are provided. The method includes switching a plurality of switching devices in a power conversion component of the wind turbine system in a normal switching mode to provide power flow through the power conversion component. The method further includes switching the plurality of switches devices in the power conversion component of the wind turbine system in a short circuit switching mode to prevent power flow through the power conversion component.

On-site power generation system with redundant uninterruptible power supply

Abstract: Disclosed is a method and system for providing constant critical AC electrical load with primary, secondary, and in some cases a tertiary source of power with higher reliability and lower operating and capital costs and lower emissions than the traditional utility supply, uninterruptible power supply (UPS), and battery primary power source, and diesel generator back-up systems that are predominately used today. Specifically, the disclosed system utilizes on-site power generation to provide primary power and includes full utility and UPS/DC storage back-up systems.

Virtual power plants with combined heat and power micro-units

Abstract: The aim of the work is the integration of combined heat and power (CHP) micro-units into the low voltage network under technical and economical point of view. The whole power and gas consumption of a new residential district are measured and recorded in fifteen minutes intervals during one year. Based on these power and gas load curves the basis of a virtual power plant with CHP micro-units is analysed. With a simulation tool the operation of a CHP micro-unit is simulated. The results show the behaviour of single units in different types of houses and of all units in a virtual power plant. Furthermore they show how the operation of a CHP micro-unit must be optimized for the operation in a virtual power plant. On the basis of this technical parameters a business model for an virtual control power plant is presented and calculated

Method for satisfying variable power demand

Abstract: A process for satisfying variable power demand and a method for maximizing the monetary value of a synthesis gas stream are disclosed. One or more synthesis gas streams (18; 20; 26) are produced by gasification of carbonaceous materials and passed to a power producing zone (38) to produce electrical power during a period of peak power demand or to a chemical producing zone (54) to produce chemicals such as, for example, methanol, during a period of off-peak power demand. The power-producing zone (38) and the chemical-production zone (54) which are operated cyclically and substantially out of phase in which one or more of the combustion turbines are shut down during a period of off-peak power demand and the syngas fuel diverted to the chemical producing zone. This out of phase cyclical operational mode allows for the power producing zone (38) to maximize electricity output with the high thermodynamic efficiency and for the chemical producing zone (54) to maximize chemical production with the high stoichiometric efficiency. The economic potential of the combined power and chemical producing zones is enhanced.

Power System Requirements for Wind Power

Abstract: The power system requirements for wind power mainly depend on the power system configuration, the installed wind power capacity, and how the wind power production varies. Wind resources vary on every time scale: seconds, minutes, hours, days, months and years. On all these time scales, the varying wind resources affect the power system. An analysis of this impact will be based on the geographical area that is of interest. The relevant wind power production to analyse is that of larger areas, like synchronously operated power systems, comprising several countries or states. The integration of wind power into regional power systems is mainly studied on a theoretical level, as wind power penetration is still rather limited. Even though the average annual wind power penetration in some island systems (e.g. Crete in Greece) or countries (e.g. Denmark) is already high, on average wind power generation represents only 1–2 % of the total power generation in the Scandinavian power system (Nordel) or the Central European system (UCTE). And the penetration levels in the USA (NERC regions) are even lower. Most examples in this chapter come from Central and Northern Europe, as there is already some experience with large-scale integration of wind power, and there are farreaching targets for wind power. In Central Europe, power production is mostly based on thermal production, whereas in the Nordic countries thermal production is mixed with a large share of hydro power. We will refer to the energy penetration when we use the term wind power penetration in the system. The energy penetration is the energy produced by wind power (annually) as a percentage of the gross electricity consumption. Low penetration means that less than 5 % of gross demand is covered by wind power production, high penetration is more than 10 %. First, this chapter will describe the power system and large-scale wind power production. We will then look at the effects of wind power production on power system operation as well as present results from studies in order to quantify these effects.

Generation control in small isolated power systems

Abstract: Recently, interest in isolated small power systems is rapidly increasing. This interest is due to the fact that larger power plants are economically unfeasible in many regions due to increasing system and fuel costs. When the system operates in isolation then load tracking problem arises which can cause voltage and frequency problems. One possible solution to keep power balance in the system and to have generation control is to use DC battery storage. This paper present a study of the generation control in small isolated power network based on grid voltage control and the storage frequency control.

Bounding active power generation of a wind-hydro power plant

Abstract: In the usual operation, wind park production is strongly dependent on the instantaneously available wind power When energy storage is accessible, the wind park operation can be improved, aiming to a better exploitation of the available wind power resource The present work proposes an optimization approach to determinate the most probable range of the output production, to be used in the definition of production profiles that will help the participation of wind power in the market Two production profiles strategies were analyzed and compared The forecasted wind power is represented as a stochastic variable and real wind power Portuguese conditions have been used in the evaluation of the model

Ac Power Supplying System, Power Supply Apparatus, and Vehicle Having the Same

Abstract: Upon power failure of a commercial power source, an automatic switching device switches to power supply from a hybrid vehicle. An ECU of the vehicle, when receiving a request for generation of a commercial AC voltage, sets an upper-limit power generation amount based on a remaining amount of fuel. The ECU transmits the upper-limit power generation amount via an antenna to an on-premises ECU, while controlling a power generation amount based on the upper-limit power generation amount. The on-premises, when receiving the upper-limit power generation amount, controls the load state such that commercial AC power is supplied firstly to a first load of priority level 1, according to proprieties registered in advance, and such that the amount of the power supplied to the electric loads does not exceed the upper-limit power generation amount.

Power system for area containing a set of power consumers

Abstract: There is provided a power system for an area containing a set of power consumers which can be applied to a collective housing consisting of a single or more buildings and can prevent power supply stop of a supply line having a higher priority. The system includes: means for cutting off each of the power supply lines in a single power consumer section from a remote management section by remote operation; means for setting the power consumption limit amount within the maximum power that can be supplied to the single power consumption section via the Internet; and means for setting the power supply priority for the power supply lines in advance and outputting an instruction to cut off power in the power supply line having the lowest power supply priority by the remote out-off means when the remote measurement value of the total power consumption amount exceeds the set value of the power consumption limit amount.

Load profile synthesis and wind power generation prediction for an isolated power system

Abstract: This paper investigates the load composition by load survey study and predicts the wind power generation with a probabilistic network for an isolated power system. The power consumption by each customer-class with the application of load patterns and the total power consumption of all customers within the same class can be obtained and calculated. Probabilistic neural network (PNN) solves the wind power generation based on the wind speed for an offshore island in Taiwan. With the hourly wind speed and load composition, the power generation of diesel generators has been obtained. Results of this study demonstrate that wind power generation can economically and effectively replace the generation of the diesel power plant and provide partial power supply capability for the net peak load requirement

Generating Power Leveling of Renewable Energy for Small Power System in Isolated Island

Abstract: Wind turbine generators and PV system causes fluctuating power condition. Therefore, the fluctuating power causes frequency and voltage fluctuations. In order to solve this problem, we propose a new power supply system by using renewable energy power production plant in isolated island. The feature of this system is to use hydrogen production unit and fuel cell. The operation of suggested system absorbs fluctuating power of renewable energy. Furthermore, the proposed system is able to generate reactive power by using three phase inverter. The effectiveness of the proposed power supply system is shown through simulation results

Improved accounting of emissions from utility energy storage system operation.

Abstract: Several proposed utility-scale energy storage systems in the U.S. will use the spare output capacity of existing electric power systems to create the equivalent of new load-following plants that can rapidly respond to fluctuations in electricity demand and increase the flexibility of baseload generators. New energy storage systems using additional generation from existing plants can directly compete with new traditional sources of load-following and peaking electricity, yet this application of energy storage is not required to meet many of the Clean Air Act standards required of new electricity generators (e.g., coal- or gas-fired power plants). This study evaluates the total emissions that will likely result from the operation of a new energy storage facility when coupled with an average existing U.S. coal-fired power plant and estimates that the emission rates of SO2 and NOx will be considerably higher than the rate of a new plant meeting Clean Air Act standards, even accounting for the efficiency benefits of energy storage. This study suggests that improved emissions "accounting" might be necessary to provide accurate environmental comparisons between energy storage and more traditional sources of electricity generation.

Impact of wind energy in a future power grid

Abstract: This thesis investigates on various levels the technical impact of wind power on a power system. The first part develops detailed dynamic models of wind turbines or farms in software dedicated to power system simulation. These models are used to assess the impact of wind speed or power grid disturbances. The models are a suitable tool to investigate the turbine's ability to provide 'ancillary services', i.e. voltage control or other types of grid support, and to assess the impact of adapting grid connection requirements specifically for wind turbines. The second part quantifies the hourly and daily power output fluctuations of an aggregated wind park for the specific case study of the Belgian control zone, for various scenarios. Furthermore, the potential contribution to the abatement of carbon dioxide emissions by the total power generation park is assessed. The final part presents the results of a multidisciplinary study with regard to optimal offshore wind developments in the Belgian Continental Shelf, including aspects with regard to seabed properties, wind resources, turbine types and power system availability.

Power control apparatus and method for electrical system of vehicle

Abstract: A power control apparatus acquires a maximum supply amount of power, transient maximum supply amount of power, and transient minimum supply amount of power of each power supply source. The apparatus further acquires a power cost of respective power supply sources, a load-required power and a charge request power. The apparatus acquires a combination of power supply sources that minimizes specific fuel consumption and determines an allocation amount of power. Taking transient response of respective power supply sources into account, the allocation amount of power of each power supply sources is corrected to be greater than a transient minimum supply power and smaller than a transient maximum supply power.