Cristián Cárdenas-Lailhacar

A Case Study for Energy Auditing Using an Interactive Energy Balance

The two previous articles in this series have described how to create an energy balance (Analyzing Facility Energy Use: A Balancing Act) [1], and how to expand the basic energy balance spreadsheet to include a number of economic analysis measures (Energy Balancing-How to Use the Energy Balance Data You Have Collected to Make Financial Decisions) [2]. Simultaneously, another article (An Interactive Energy Balance: A Case Study) [3] was published which emphasized concepts and improved the ideas of the previous ones through an interactive, user-friendly software. In this article-the third in the series-we describe this new interactive software that allows the user to perform an energy balance for a facility more easily and efficiently. This new, interactive software provides a graphical user interface, or GUI, to expedite the entry of data, using menus whenever possible. Large amounts of data on facility energy bills, facility equipment, and operating characteristics are still required, but the new interactive software greatly speeds up this data entry process and reduces the chances for data entry errors. In addition, the process of adjusting facility equipment and operating characteristics to match the actual energy consumption is improved and compressed so that this critical task is also performed with less manual effort. All the energy consumption data are displayed in graphs and pie charts. Moreover, calculations of potential energy savings recommendations are performed for each type of equipment considered. The end result is an energy balance software tool that is much easier to use than any of our previous Excel spreadsheets. This increased ease of use makes it much more likely that other people will use this tool to assist them in their energy auditing studies, making decisions to purchase new equipment, or upgrading less efficient equipment. The article concludes with a case study that provides insight on the faster data entry and balancing process, graphical display, and recommendations, as well as further demonstrating the value of the energy balance approach.

A Cogeneration Case Study Using the Interactive Energy Balance Program

ABSTRACT Cogeneration is a highly effective means of increasing energy efficiency and reducing energy costs by utilizing the heat that would normally be wasted and use some or all of it for the thermal requirements of a facility. This effective utilization of heat generated during electricity production allows for an increase of fuel efficiency from 35% to almost 85%. Cogeneration not only reduces energy costs and increases energy efficiency, but is also beneficial to the environment by reducing the amount of pollutants that are emitted into the atmosphere. In a previous work we presented and described the new Interactive Energy Balance (IEB) software. The package offers an easy way to account for energy bills, working equipment and their energy operating characteristics. Among the equipment considered are: lighting, air conditioning, refrigeration compressors, air compressors, motors, and others. The electric energy consumed by all pieces of equipment is balanced against the energy bills (last 12 months)...

Finding Transition States Using the LTP Algorithm

Preliminary results using the Line-Then-Plane (LTP) procedure to find Transition States (TS) in simple chemical systems are here presented. With slight modifications the algorithm has been implemented in the ZINDO program package, and has proven to require less computer time than other procedures that demand the full evaluation of the Hessian. We demonstrate that this procedure is able to give a good approximation of the minimum energy reaction path.

Hardness and the Potential Energy Function in Internal Rotations: A Generalized Symmetry-Adapted Interpolation Procedure

Density functional theory (DFT) has provided the theoretical basis to study reactivity parameters of molecular systems, this is, to its resistance to change its electron density distribution, namely the molecular hardness (ŋ). Its evolution along a given reaction coordinate is examined in order to better understand the chemical reactivity of the system of interest. In this work, compounds that are often used as prototypes to study their linkage in proteins are shown.