Many software packages can help predict energy use
Editor's note: The Energy Services Bulletin features real answers to real questions posed to our staff at the Energy Services Power Line. We hope you find it useful.
Question:
An individual recently contacted us for energy usage information on a proposed new 67,000-square-foot assisted living center. It will have common areas, pool, full kitchen and dining facilities and 100 rooms with air-conditioning and heating. Gas will be used for water heating and cooking. The walls will be insulated to R-20, and R-38 in the ceiling. Do you know of any software that can be used to predict energy use for facilities?
Answer:
The best place to see most of the software packages available and compare their features is at the U.S. Department of Energy's Web site. The Tools Directory lists building energy software at "Whole Building Analysis." This site gives full descriptions of each software package and highlights those that are free.
Here are some of the more common packages:
- EnergyPlus is a new generation building energy simulation program that builds on the most popular features and capabilities of BLAST and DOE-2. EnergyPlus includes innovative simulation capabilities, including time steps of less than an hour, modular systems and plant integrated with heat balance-based zone simulation, multi-zone air flow, thermal comfort and photovoltaic systems. Other planned simulation capabilities include solar thermal, multizone airflow, and electric power simulation including photovoltaic systems and fuel cells. Cost: Free
- EZ Sim is a quick spreadsheet tool that is equivalent to sophisticated engineering analysis. The program uses utility bills to calibrate a simulation of a commercial facility in an interactive graphic window. Once it matches your bills, the simulation model can provide reliable estimates of potential conservation savings. The calibration process reveals how a facility uses energy and helps diagnose the cause of excessive consumption or poorly functioning building components. Case study examples can be reviewed on the Web site. The model also provides precision and confidence limits of savings estimates consistent with IPMVP performance verification protocol. Cost: $199 and $299
- eQUEST is a sophisticated, yet easy-to-use, freeware building energy use analysis tool which provides professional results with an affordable level of effort. It allows the user to perform detailed comparative analysis of building designs and technologies by applying sophisticated building energy use simulation techniques without requiring extensive experience in the "art" of building performance modeling. This is done by combining schematic and design development building model creation wizards with an energy efficiency measure wizard and a graphical results display module with an enhanced DOE-2-derived building energy use simulation program. Cost: Free
- DOE-2 offers an hourly, whole-building energy analysis program for calculating energy performance and life-cycle operation cost. It can be used to analyze energy efficiency of given designs or efficiency of new technologies. Other uses include utility demand-side management and rebate programs, energy efficiency standard development and implementation and compliance certification and training new corps of energy-efficiency conscious building professionals in architecture and engineering schools. Cost: Free
- PowerDOE is a powerful and flexible building energy use and cost estimation tool. It includes a graphical user interface that provides 2-D and 3-D displays of your building layout, including architectural and HVAC features, as well as graphical modeling results. PowerDOE includes DOE-2.2 as its simulation "engine" for all energy and cost calculations. PowerDOE is a complete implementation of DOE-2.2 features, including all its new interactive features for dynamic recalculation of defaults during use. Cost: $278
This is just a sampling of what is available. We encourage you to take the time to look through the whole list of available software before you make your decision to choose the appropriate software to meet your project's needs.