A Novel Microgrid Demand-Side Management System for Manufacturing Facilities

Thirty-one percent of annual energy consumption in the United States occurs within the industrial sector, where manufacturing processes account for the largest amount of energy consumption and carbon emissions. For this reason, energy efficiency in manufacturing facilities is increasingly important for reducing operating costs and improving profits. Using microgrids to generate local sustainable power should reduce energy consumption from the main utility grid along with energy costs and carbon emissions. Also, microgrids have the potential to serve as reliable energy generators in international locations where the utility grid is often unstable. For this research, a manufacturing process that had approximately 20 kW of peak demand was matched with a solar photovoltaic array that had a peak output of approximately 3 KW. An innovative Demand-Side Management (DSM) strategy was developed to manage the process loads as part of this smart microgrid system. The DSM algorithm managed the intermittent nature of the microgrid and the instantaneous demand of the manufacturing process. The control algorithm required three input signals; one from the microgrid indicating the availability of renewable energy, another from the manufacturing process indicating energy use as a percent of peak production, and historical data for renewable sources and facility demand. Based on these inputs the algorithm had three modes of operation: normal (business as usual), curtailment (shutting off non-critical loads), and energy storage. The results show that a real-time management of a manufacturing process with a microgrid will reduce electrical consumption and peak demand. The renewable energy system for this research was rated to provide up to 13% of the total manufacturing capacity. With actively managing the process loads with the DSM program alone, electrical consumption from the utility grid was reduced by 17% on average. An additional 24% reduction was accomplished when the microgrid and DSM program was enabled together, resulting in a total reduction of 37%. On average, peak demand was reduced by 6%, but due to the intermittency of the renewable source and the billing structure for peak demand, only a 1% reduction was obtained. During a billing period, it only takes one day when solar irradiance is poor to affect the demand reduction capabilities. To achieve further demand reduction, energy storage should be introduced and integrated

Microgrids for Improving Manufacturing Energy Efficiency

Thirty-one percent of annual energy consumption in the United States occurs within the industrial sector, where manufacturing processes account for the largest amount of energy consumption and carbon emissions. For this reason, energy efficiency in manufacturing facilities is increasingly important for reducing operating costs and improving profits. Using microgrids to generate local sustainable power should reduce energy consumption from the main utility grid along with energy costs and carbon emissions. Also, microgrids have the potential to serve as reliable energy generators in international locations where the utility grid is often unstable. For this research, a smart microgrid system was designed as part of an innovative load management option to improve energy utilization through active Demand-Side Management (DSM). An intelligent active DSM algorithm was developed to manage the intermittent nature of the microgrid and instantaneous demand of the site loads. The controlling algorithm required two input signals; one from the microgrid indicating the availability of renewable energy and another from the manufacturing process indicating energy use as a percent of peak production. Based on these inputs the algorithm had three modes of operation: normal (business as usual), curtailment (shutting off non-critical loads), and energy storage. The results show that active management of a manufacturing microgrid has the potential for saving energy and money by intelligent scheduling of process loads

The effect of visual analysis skills on conceptual understanding and problem-solving in electrical circuits

The purpose of this study was to investigate the effectiveness of a supplementary visual analysis instructional unit on electrical circuit diagram simplification. More specifically, the study examined how this unit would affect students\u27 ability to recognize relationships of electrical components in a visually complex circuit diagram and how the instructional unit would affect students\u27 ability to describe circuit behaviors. The population for this quasi-experimental study was all students enrolled in two sections of the Introduction to Electrical Circuits (EET 214) course at Purdue University, West Lafayette, IN. The course EET 214 was selected for three reasons: (a) the course was designed to teach electrical circuit theory for beginners, (b) it had two sections, (c) both sections were taught by one instructor, and (d) the student body of the course consisted of majors from Industrial Technology, Mechanical Engineering Technology, and Computer Integrated Manufacturing Technology. One section of the course was selected as the experimental group and the other as the control group. A pretest was administered to both sections during the first week of the course. Following the pretest, the supplementary instructional unit was given to the experimental group. At the end of the fifth week of the course, both groups took a posttest. The test consisted of qualitative questions in order to examine the students\u27 conceptual understanding of electrical circuits. The study found that: (1) the students who received the supplementary instruction were able to identify the relationships among components of a visual complex electrical circuit more effectively, (2) the students were able to recognize the relationships more effectively when the diagrams are drawn linearly as opposed to drawn rectangularly, and (3) the students\u27 ability to describe the circuit behavior was not influenced by the visual analysis instruction

Cryptographic Key Management for Smart Power Grids

The smart power grid promises to improve efficiency and reliability of power delivery. This report introduces the logical components, associated technologies, security protocols, and network designs of the system. Undermining the potential benefits are security threats, and those threats related to cyber security are described in this report. Concentrating on the design of the smart meter and its communication links,this report describes the ZigBee technology and implementation, and the communication between the smart meter and the collector node, with emphasis on security attributes. It was observed that many of thesecure features are based on keys that must be maintained; therefore, secure key management techniques become the basis to securing the entire grid. The descriptions of current key management techniques aredelineated, highlighting their weaknesses. Finally some initial research directions are outlined