Even if you've never considered using a lighting design program, now may be the time. There are good business reasons why you should check into such software.
As lighting installations become increasingly more complex, separate ambient, task, and security illumination take on greater importance. New light sources and technologies (such as remote source lighting) also complicate design issues. State and federal energy requirements often define a maximum power density for lighting in new construction. With all of these factors to consider, where do you turn for help? Lighting design software can make things easier and serve as an effective tool to help you refine and analyze any project.
A look at the market. The industrial plant lighting market is ripe with opportunities. Generally, each facility has its own spatial conditions and task requirements. With a lighting design program, you can prepare several design solutions using different lamp/system combinations to determine variances in performance and economics. Each solution also can include a return-on-investment (ROI) evaluation.
The growing use of these programs by contractors is already speeding and simplifying the process of handling bid work, design/build contracts, and retrofit projects.
Many lighting installations are coming into the second or even third generation of retrofits. Though previous retrofits may have saved some energy dollars, many have also caused a diminished visual environment. In some cases, they've simply provided poor quality lighting. The biggest opportunity for contractors today is high-efficiency, high-quality fixtures, and lighting controls for a complete relighting. This is especially true for fluorescent and metal halide applications. In this case, a software program can help turn a proposal into a sale.
Don't forget about the increasing importance of lighting controls. You can use lighting control software to cut the time required to specify, design, and document preset dimming control in half. Modern lighting control schemes can help create "just the right" atmosphere. Well-integrated controls can also enhance security and reduce energy costs.
What's new and useful? Still think you don't need any kind of lighting design program? Suppose you're involved in lighting renovation/energy-saving upgrade projects. If you need assistance, two free software programs are available from U.S. government agencies:
(1) The Environmental Protection Agency (EPA) offers Project Kalc, which is available from its website (epa.gov). This program provides a full analysis of a planned lighting upgrade, including relamping, controls, tandem wiring, and more. It also includes a user-modifiable database of costs, labor time, and performance for more than 8000 hardware components.
(2) A public domain program, called Federal Lighting Energy Expert (FLEX), is available from the Federal Energy Management's website (eren.doe.gov). It allows you to evaluate an energy-saving relighting project using a number of efficient lighting products. Designed for federal relighting projects, the program runs under DOS and is for Windows, Windows95, or OS/2.
From calculations to virtual reality. Evolution is the keyword for lighting software programs. In the "old" days, we only used these programs to do complex calculating functions rapidly. Today's modern programs can take you on a virtual 3-D color tour of the lighted space. This transforms your computer or workstation into a video tool that allows you to see how a proposed design will look with the installed lighting equipment. The result: a better design solution in less time with greater assurance of accuracy.
An important development spurring the use of such software is the easy availability of photometric data files. Major lighting fixture manufacturers and photometric laboratories archive luminaire photometric data in accessible databases, using the most popular formats. One new program uses a Windows format to automatically evaluate the electrical requirements and loads for each room and select the best solution. You enter load information and control points. Then, the program uses this input to create one-line diagrams, equipment schedules, bills of material, specifications and dimming panel schedules (if needed).
Where to find program comparisons. The best source of information on computer software is the Illuminating Engineering Society of North America (IES), which conducts an annual survey on available products. The latest survey (printed in the October 1998 issue of the association's monthly magazine, Lighting Design and Application or LD&A) includes 27 lighting design software programs.
A table with nine major headings shows the survey results. Sample headings include "Price," "Applications," "Hardware Requirements," and "Types of Analysis." The table lists some elements as acronyms. For example, the required Operating System elements include Win95/NT, Unix, or DOS. The survey defines system memory requirements in megabytes (Mbs) or kilobytes (Kbs). Other features use letter designations.
The first heading of interest is probably "Price." One fixture manufacturer has two free programs and one that costs only $100. Programs offered by other fixture manufacturers (or the Electric Power Research Institute) cost only a few hundred dollars and should satisfy most contractors and engineers. Programs sold by independent software firms range in price from the same few hundred dollars to $10,000. Of course, the higher priced products are for very detailed analysis.
The "Special Features" heading lists particular capabilities of the program. For example, "automatic layout" means the program will suggest a layout of the luminaires. "Generate schedules" means it will produce a luminaire schedule for the building. "Building shadowing" means the calculations take into account the shadowing effects of other buildings in outdoor analysis. "Batch processing" means the program can run several analyses while the computer is unattended. "Interior obstructions" means the program calculations take into account the effects of user-defined obstructions in interior spaces.
An "Economic Analysis" checkmark indicates the program will calculate cost considerations for the lighting system. For example, one popular program (from an independent software company) costs about $600 and offers a photometric library of more than 17,000 products from more than 60 manufacturers. Using a Windows operating system, it provides a familiar, easy-to-use graphical user interface, pull down menus, and toolbars. It's also resizable.
Other features of lighting software include a CAD interface with import and export capabilities; gray scale images; project file merging; and a variety of report types of customized output. It also offers predefined objects (such as partitions, tables, and chairs) you can add to a rendered space with a mouse. In addition, you can use a second software program in tandem to produce full-color, photographic quality images.
According to IES, other important features to look for in a lighting software package include:
If it operates inside of (and requires) a CAD program to function.
If you can enter data into tables on the screen.
If it accepts input from a digitizer, keyboard, mouse, pen, or voice commands.
If it has provisions for multilingual support or CIE calculations, which are European standards.
Can view graphs of photometric distributions on the screen?
If you can tilt light meters.
If it uses the Zonal Cavity Method for indoor calculation for average illuminance value.
If it uses the Lumen Method to get the average illuminance value for an area.
If it offers roadway luminance and daylighting capabilities.
If technical support is available, and documentation is provided online or available in a printed manual.
Sidebar: Example of 3-D Modeling in CAD
Here's how 3-D modeling creates images that were impossible a few years ago. This modeling was the basis for the lighting design of a corporate headquarters, completed only a few years ago. Gesner and Associates, a San Francisco-based architectural firm, began by working out two-dimensional sketches on a computer. Then, the firm built scale models to show its client in more detail what the architects had in mind. From these, the firm returned to CAD for plans and sections. After the client selected one of the schemes, Gesner and Associates generated a 3-D computer model that enabled th e firm to conduct internal and external light studies.
From within the CAD program, the Gesner design team created a series of >images that served as the basis for a video. Projected on a large >television screen, the video allowed the client to "walk through" the >space of the museum and boardroom. Then, the architect showed the video to >the general contractor and subcontractors so they could visualize >construction. Then, these contractors offered refinements on the details >to improve them.