The deregulation of the electric power market introduced a strong element of competition. Power plant operators strive to develop advanced operational strategies to maximize the profitability in the dynamic electric power market. New methodologies for gas turbine power plant operational modeling and optimization are needed for power plant operation to enhance operational decision making, and therefore to maximize power plant profitability by reducing operations and maintenance cost and increasing revenue. In this study, a profit based, lifecycle oriented, and unit specific methodology for gas turbine based power plant operational modeling was developed, with the power plant performance, reliability, maintenance, and market dynamics considered simultaneously. The generic methodology is applicable for a variety of optimization problems, and several applications for operational optimization were implemented using this method. A multiple time-scale method was developed for gas turbine power plants long term generation scheduling. This multiple time-scale approach allows combining the detailed granularity of the day-to-day operations with global (seasonal) trends, while keeping the resulting optimization model relatively compact. Using the multiple timescale optimization method, a profit based outage departure planning method was developed, and the key factors for this profit based approach include power plant aging, performance degradation, reliability deterioration, and the energy market dynamics. A novel approach for gas turbine based power plant sequential preventive maintenance scheduling was also introduced. Finally, methods to evaluate the impact of upgrade packages on gas turbine power plant performance, reliability, and economics were developed, and TIES methodology was applied for effective evaluation and selection of gas turbine power plant upgrade packages.

Demand is emerging for offshore wind power plant (WPP) that often has favorable capacity factor and high capacity value as compared with onshore wind farms. There are many challenges regarding power losses, economics, protection system and reliability of the wind farm. Collection system design decisions play an essential role to efficient operation of the WPP. Wind generators also have to be able to cope with grid disturbances. Low voltage ride-through (LVRT) capability of wind turbines requires generator units remain in operation for severe voltage drops during ¡@grid system faults, and be able to withstand depressed voltage for a few seconds in a recovery period. Technical requirements set out in grid codes for off shore wind farm normally relate to different connection points. A rigor LVRT requirement would increase the overall investment costs of the wind farm. In most offshore wind farm projects, radial collector systems connecting a number of wind turbines and terminated at the offshore platform have served well the requirements for an economical design. However, due to the lack of redundancy, its reliability is poor. To improve the reliability of the collector system, the inclusion of a cable section that interconnects the remote ends of two adjacent radial feeders has been proposed. The transmission system of a wind farm takes the power generated and sends it to shore. Medium voltage AC transmission is the simplest one, just gathering the cables from the collector system and taking them together until they reach the point of common coupling (PCC).Through wind farm dynamic simulations by using DIgSIENT package, this thesis demonstrates that the ride through capability which occur at the particular wind parks with different collector system topology are greater than those which the wind turbines are capable of riding through, i.e., LVRT curves of different wind farm collection system designs of an offshore WPP and a single wind generator are different. This can be exploited to reduce the cost in complying with LVRT requirement of offshore WPP.

Manure-based biomass (MBB) has the potential to be a source of green energy at large coal-fired power plants and on smaller-scale combustion systems at or near confined animal feeding operations. Although MBB is a low quality fuel with an inferior heat value compared to coal and other fossil fuels, the concentration of it at large animal feeding operations can make it a viable source of fuel. Mathematical models were developed to portray the economics of co-firing and reburning coal with MBB. A base case run of the co-fire model in which a 95:5 blend of coal to low-ash MBB was burned at an existing 300-MWe coal-fired power plant was found to have an overall net present cost of $22.6 million. The most significant cost that hindered the profitability of the co-fire project was the cost of operating gas boilers for biomass dryers that were required to reduce the MBB's moisture content before transportation and combustion. However, a higher dollar value on avoided nonrenewable CO2 emissions could overrule exorbitant costs of drying and transporting the MBB to power plants. A CO2 value of $17/metric ton was found to be enough for the MBB co-fire project to reach an economic break-even point. Reburning coal with MBB to reduce NOx emissions can theoretically be more profitable than a co-fire project, due to the value of avoided NOx emissions. However, the issue of finding enough suitable low-ash biomass becomes problematic for reburn systems since the reburn fuel must supply 10 to 25% of the power plant?s heat rate in order to achieve the desired NOx level. A NOx emission value over $2500/metric ton would justify installing a MBB reburn system. A base case run of a mathematical model describing a small-scale, on-the-farm MBB combustion system that can completely incinerate high-moisture (over 90%) manure biomass was developed and completed. If all of the energy or steam produced by the MBB combustion system were to bring revenue to the animal feeding operation either by avoided fueling costs or by sales, the conceptualized MBB combustion system has the potential to be a profitable venture.

In this thesis an apparatus is designed which enables the testing of thermal power plant boiler tubes against erosion. The apparatus makes use of a tube sample directly cut from the boiler tubes and simulates conditions similar to those prevailing in boilers in lignite fired power plants. The apparatus is composed of three components / a furnace for heating the sample, a loading system which allows application of tensile stresses while allowing the rotation of the sample, and a particle blower that delivers abrasive particles to the surface of the sample. The abrasive material used in the test is mixture of oxides, 90% of which is Al2O3 and the average particle size is approximately 300 &micro / m. The unit as designed would allow testing of boiler tubes up to a temperature of 650 C, and particle velocity of up to 50 m/s. The apparatus as tested at room temperatures for four identical samples have yielded very similar erosion values based on measurement of weight loss. At elevated temperature, erosion could be measured by a thickness loss since the oxidation that occurs complicates the erosion measurement. Two economizer material / P235GH and 16Mo3 were tested at 500oC with particle velocity of 10 m/s. The testing has shown that 16Mo3 has better performance than P235GH, the erosion rate differing by 20 percent.

Electricity Liberalization Independent Power Plant Project Finance Electricity Pool Biletral Contract

Abstract In recent years, domestic energy policy has continuously changed, especially, after a liberalization of electric power market opened, resulting into the power industry proprietor expected to has a stable electric power supply systems, high power generation, high thermal efficiency and low heat rate. They will consistently devise a way to propose a strategy of improved or enhanced in the light of a competitive footstone for electric force market. About 90% worldwide and 65% domestic electricity are generated by the thermal power plants, where the energy source is obtained from burning the fossil fuels. Therefore, Increasing the power generation capacity of thermal power plants will substantially raise to the percent reserve margin of to be smaller than 12% over the years. In Taiwan, the ambient temperature is always higher than 30oC at summer. When gas turbine has operated during peak, gave rise to deteriorate its power generation capability and often actually generated power lower 10% than based on a design condition of ISO 15oC. This study adopts a way which is not same as conventional method increased power generation capability of the thermal power plants. In other word, reducing the inlet air temperature to gas turbine, it will increase the air flow mass rate and the generated-power capacity. By means of EPRI Gate Cycle Software constructing a typical combined-cycle power plant, at the same time, to simulate and to search out an effective operating control strategy for the power plant with GTIAC. Furthermore, applying the electric chiller and the absorption chiller to combined-cycle power plant as an inlet air cooling system use thermodynamic and engineering analysis to discuss an extent of energy utilizing, the valuability of energy application, to access the economic effect of investing equipment to acquire an optimal balance point. Selecting the inlet air temperature 15oC,10oC and comparing the thermal performance of electric chiller with that of absorption chiller. Then, proposing a feasible suggestion to treat as an important reference criteration of improving present power GENSET and planning to install a thermal power plant for the electric power proprietor.

Following an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied.

Real options have been widely applied to analyze investment planning and asset valuation under uncertainty in many industries, especially energy markets. Because of their close analogy to financial options, real options can be valued using the classical financial option pricing theories and their extensions. However, as real options valuation often involves complex payoff structures and operational constraints of the underlying real assets or projects, accurate and flexible methods for solving the valuation problem are essential. This thesis investigates three different approaches to real options valuation and contributes to aspects of modeling realism and computational efficiency. The contributions are illustrated through two important applications of real options in energy markets: natural gas storage and power plant valuation. Because spread options are commonly used in basic real options valuation techniques, the first part of the thesis addresses the problems of spread option pricing and hedging. We develop a new closed-form approximation method for pricing two-asset spread options. Numerical analysis shows that our method is more accurate than existing analytical approximations. Our method is also extremely fast, with computing time more than two orders of magnitude shorter than one-dimensional numerical integration. Closed-form approximations for the Greeks of spread options are also developed. In addition, we analyze the price sensitivities of spread options and provide lower and upper bounds for digital spread options. We then further generalize the above results to multi-asset spread options on an arbitrary number of assets. We provide two new closed-form approximation methods for pricing spread options on a basket of risky assets: the extended Kirk approximation and the second-order boundary approximation. Numerical analysis shows that both methods are extremely fast and accurate, with the latter method more accurate than the former. Closed-form approximations for important Greeks are also derived. Because our approximation methods enable the accurate pricing of a bulk volume of spread options on two or more assets in real time, it offers traders a potential edge in a dynamic market environment. In the third part of this thesis, we propose a market-based valuation framework for valuing natural gas storage facility with realistic operational characteristics. The operational process is modeled as a multi-stage stochastic optimization problem. We develop a Gaussian quadrature scheme to solve for the dynamically optimal spot trading strategy and show that the computational efficiency of this method exceeds existing approaches in about two orders of magnitude. Furthermore, with this flexible quadrature scheme, we propose to value a gas storage based on a novel hybrid trading strategy that successfully incorporates both spot and forward trading, thus improving the storage valuation significantly by accounting for both the inter-month and intra-month operational flexibilities and price volatility. In the fourth part of this work, we develop a continuous-time formulation for power plant valuation in infinite time horizon. We propose a real-option-based model for a power plant to account for the embedded operational flexibility. This model incorporates start-up and shut-down costs as two major operational constraints. Under this continuous valuation model, spark spread is modeled directly as a continuous stochastic process to take account of the long term co-integration relationship between electricity and fuel prices. Instead of discretizing the stochastic process, we preserve continuity of the stochastic spark spread process and work directly with the value function. Closed-form of value function under threshold policy is obtained. The corresponding optimal operational strategy can then be solved. The advantage of this approach is that it reduces computational complexity while incorporates major operation characteristics. It enables fast computation of a power plant value that approximates the real market value and sensitivity analysis of the asset value with respect to the cost parameters of a power plant and the distribution parameters of spark spread.

Arsenic (As) poses a significant water quality problem and it is a big challenge for all coal-based power plant industries worldwide. Currently most of the researches on the leaching behavior of arsenic from fly ash are based on the titration experiments. In this study a simulation method is used to study on the pH effect on the arsenic separation of coal-based power plants. Both single point and composition survey simulation of the OLI stream analyzer are used in the study. The simulation results of single point calculation indicates that for the fly ash which has high lime weight percent and equilibrium fly ash solution pH is over 11 and between 7 and 9, that is, Type C fly ash, the simulation results for equilibrium pH in fly ash solutions have great accuracy compared to actual experiment results. Based on the results obtained from single point simulation, both acid and base titrations of composition survey are simulated and the output results suggest that for the same type of fly ash, the simulation results proves the general trend of arsenic solubility in fly ash solutions. The solubility of arsenic decreases with the increase of pH value. It is also noted that at the equilibrium pH fly ash solutions, the maximum solid/liquid ratio of arsenic concentration is observed for type C fly ash. For other fly ashes which have low lime weight percent, the simulation results have discrepancy compared to actual experiment results. This work is important in offering an alternative way of analyze the reasonable output species and relative concentrations for type C fly ash in the waste water storage pond under specific pH conditions, which can be of great importance for the power plants to monitor and minimize the environment pollution in order to meet the future federal regulations.

Thesis (M. Soc. Sc.)--University of Hong Kong, 1988.