Hans B. Puttgen

Distributed generation: Semantic hype or the dawn of a new era?

As the electric utility industry continues to restructure, driven both by rapidly evolving regulatory environments and by market forces, the emergence of a number of new generation technologies also profoundly influences the industrys outlook. While it is certainly true that government public policies and regulations have played a major role in the rapidly growing rate at which distributed generation is penetrating the market, it is also the case that a number of technologies have reached a development stage allowing for large-scale implementation within existing electric utility systems. At the onset of any discussion related to distributed generation, one question begs to be answered: is the fact that electric power producing facilities are distributed actually a new and revolutionary concept? Have power plants not always been located across broad expanses of land? The answer to these questions clearly is that electric power plants have always been sited all across the service territories of the utilities owning them. Hence, the opening question: as with many so-called innovations that have been put forward during the recent past, is the entire concept of distributed generation a simple semantic marketing hype or are we actually at the dawn of a new electric power generation era? We believe that a new electric power production industry is emerging, and that it will rely on a broad array of new technologies. This article sets the stage for distributed generation covering such topics as: the present power production situation; what distributed generation is; capability ratings and system interfaces; market penetration of internal combustion engine generators, fuel cells and microturbines; potential generation mix issues, network considerations including power quality, reactive power coordination, reliability and reserve margin, reliability, network redundancy, safety and accountability; public policy and regulatory impact; and standards.

Optimum scheduling procedure for cogenerating small power producing facilities

A comprehensive model of a small power-producing facility (SPPF) is discussed to determine its optimum operational schedule under utility energy-spot-pricing policies. The model is particularly well suited for SPPFs with both topping and bottoming cogeneration cycles in that the various thermal energy flows are explicitly modeled along with the electrical energy flows. The optimum scheduling algorithm is based on a linear programming method that provides for the explicit inclusion of the various thermal and electrical operating constraints. A realistic performance index, based on the true SPPF revenues and costs, is used in the linear programming procedure. >

Restructuring and Reregulation of the U.S. Electric Utility Industry

To exploit the information of power market activities, a bootstrap technique is proposed in the available transfer capability (ATC) calculation. This is a computer-based method for assigning accuracy to statistical estimates. The standard confidence intervals calculated provide useful information to transmission customers in their evaluation of transaction bids and purchase of transmission right.

Optimization Topics Related to Small Power Producing Facilities Operating under Energy Spot Pricing Policies

Small Power Producing Facilities will become more and more common as the various provisions of the Public Utility Regulatory Policies Act (PURPA) are taken advantage of by utility and customers. These facilities incorporate several features which allow the user to increase his operational flexibilty with respect to the local utility. These facilities can be: local generation, local dependent generation, local energy storage facility, and shiftable load schedule. The only true control the utility has over the actual operation of such facilities is through the judicious selection of the energy prices proposed to such users both for the sale and purchase of energy. It is likely that most utilities will react to this novel user-utility relationship by implementing time-varying energy prices to better reflect their own production costs. These time varying energy prices are often referred to as Spot Prices and are rather commonly used in Europe. A key issue is then the simulation of the various SPPF loads under various spot pricing policies and as they would be seen from the utilitys point of view. The purpose of the paper is to describe a general and flexible model for a large variety of SPPFs and to demonstrate its use on a number of operations planning and plant design problems.

Adjoint Network Sensitivity Based State Variable Evaluation for Large Scale Contingency Events

Abstract This paper addresses the determination of the power system state variables, the complex bus voltages, based on the concept of adjoint networks and Tellegens theorem. First-order sensitivities are derived and accuracy enhancements proposed to extend the validity of the state variable evaluations to cases where large-scale perturbations occur in the network. Practical implementation issues are addressed. Finally, numerical examples are provided for illustration purposes.

A new undergraduate course in energy conversion and mechatronics at Georgia Tech

This paper describes a new course in mechatronics that has been developed and introduced in the School of Electrical and Computer Engineering at Georgia Tech. The course is designed to serve as an introduction to electromechanical energy conversion and power electronics for both ME and EE students. The course has been designed for students with no background in this area beyond basic sophomore physics. The paper describes the goals of the course and gives an outline and description of both the lecture and laboratory portions of the course.

High voltage techniques course: a cooperative effort between Georgia Tech and Georgia Power

A cooperative effort between the School of Electrical Engineering at the Georgia Institute of Technology and the Research Center of the Georgia Power Company to establish a graduate-level course in high-voltage techniques is reported. The course contains a lecture segment and a strong experimental segment that contributes to its success. This cooperative effort enables the student to put his or her theoretical knowledge to practice in an industrial laboratory. The syllabus is outlined and experimental sessions offered during the course are described. >

Adjoint network sensitivity based performance index evaluation for large-scale contingency events

Abstract This paper addresses the determination of power system performance indices based on the concept of adjoint networks and Tellegens theorem. First-order sensitivities, as well as extensions to include expeditiously determinable higher order contributions, are dealt with. Derivations, algorithms, practical considerations, and numerical examples are presented. The relationship with state variable determination by adjoint network means is emphasized.

An Educational Interactive Program to Illustrate Equipotential Nlumerical Solution Procedures

An interactive and graphical computer program implemented in a personal computer environment is discussed. It is designed to allow students to conveniently study the electrical equipotential lines of various types of geometries found in high-voltage installations. The program uses an interactive, graphical user interface to allow students to draw the geometries to be studied directly on the display; the same display is then used to provide a visual output for the equipotential lines as computed by the program. The numerical solution procedures implemented in the program as well as the user interfaces are reviewed. A computational example is discussed along with the required hardware and software environments. >