DOE Releases New Versions of Popular Energy Simulation Software Programs

Wouldn’t it be nice to know how much energy your building would use before you build it?

Thanks to the Department of Energy (DOE), you can. The DOE has recently released an updated version of EnergyPlus, a popular energy analysis and thermal load simulation software.

EnergyPlus models heating, cooling, lighting, ventilating, and other building energy flows – as well as water. It includes many innovative simulation capabilities such as time steps of less than an hour, multizone air flow, thermal comfort, water use, natural ventilation, and photovoltaic systems.

The software’s intended users are design engineers or architects who want to size appropriate HVAC equipment, develop retrofit studies for life cycling cost analyzes, or optimize energy performance. Based on a user’s description of the building’s physical make-up, associated mechanical systems, and other factors, EnergyPlus will calculate the heating and cooling loads necessary to maintain thermal control setpoints, conditions throughout a secondary HVAC system, and the energy consumption of primary plant equipment-- as well as many other simulation details.

Version 4.0 has many new features as well as updated and extended capabilities throughout the existing building envelope, day-lighting, and equipment and systems portions of the program.

Key new features include:

• Energy management system large horizontal openings added to natural ventilation
• Walk-in refrigeration and refrigeration secondary loop
• Evaporative fluid cooler

Available for Windows, Linux, and Macintosh operating systems, EnergyPlus is a stand-alone simulation program without a 'user friendly' graphical interface. EnergyPlus reads input and writes output as text files. EnergyPlus has proven extremely popular, receiving 22,000 downloads in 2008 and 100,000 downloads since its first release in 2001. There is no charge to install and use EnergyPlus.

The DOE also released a new version of its OpenStudio plug-in for Google’s SketchUp 3D drawing program. Designed to integrate seamlessly with the SketchUp environment, the plugin allows the user to employ standard SketchUp tools to create and edit EnergyPlus zones and surfaces. Users can explore their EnergyPlus input files by using all of the native SketchUp 3D capabilities to view the building’s geometry from any vantage point, apply different rendering styles, and perform accurate shadowing studies.

With the plugin, users can mix EnergyPlus simulation content with decorative content such as background images, landscaping, people, and architectural finish details—all within the same SketchUp model. The new version also allows a user to launch EnergyPlus simulations and view the results without leaving SketchUp.