Department of Energy Releases New Software To Help Reduce Building Energy Use

April 12, 2001

Chris Kielich, 202/586-5806
April 12, 2001

EnergyPlus Simulation Program Helps Building Designers and Owners Save Money, Reduce Energy and Improve Indoor Air Quality

WASHINGTON, DC -- Secretary of Energy Spencer Abraham today released a next generation building energy simulation computer program that allows architects, engineers, building owners and managers to minimize energy use and cost and optimize building performance by simulating building energy use. The EnergyPlus program is a significant step beyond earlier Department of Energy (DOE) software, which building owners and designers have used to save an estimated $20 billion.

The Department of Energy's EnergyPlus computer simulation program will assist home builders and designers dramatically lower energy use in buildings, said Secretary Abraham. We want to help design teams and homeowners achieve energy efficiency even with tight scheduling constraints and significant dollars at stake.

EnergyPlus dramatically improves the simulation of whole-building approaches in design, planning and construction and opens new doors for energy savings, cost savings and indoor environmental quality. It allows users to calculate the impacts of different heating, cooling and ventilating equipment and various types of lighting and windows to maximize building energy efficiency and occupant comfort. Users can simulate the effect of window blinds, electrochromic window glazings, and complex daylighting systems, features not seen in earlier DOE software.

EnergyPlus can be downloaded at no cost from:

DOE developed EnergyPlus in cooperation with the U.S. Army Construction Engineering Research Laboratory, the University of Illinois, Oklahoma State University, the Department of Energy's Lawrence Berkeley National Laboratory, the Florida Solar Energy Center, and GARD Analytics.

Many well-known buildings have been constructed or renovated with DOE's previous edition of energy-efficient software, DOE-2. A partial list includes the Pentagon, the U.S. State Department headquarters, the U.S. Embassy in Berlin, the Monterey Bay Aquarium, the San Francisco Airport, the Ronald Reagan Library, the Intel and American Express corporate headquarters, numerous federal courthouses, and the Frank Lloyd Wright Museum in Wisconsin.

Highlights of the new software include:

  • Realistic system controls
  • Moisture adsorption and desorption in building elements
  • Interzone air flow
  • Low temp radiant heating/cooling
  • Interior surface convection
  • Thermal comfort modeling options
  • Evaporative cooler models
  • Steam absorption chiller
  • Air flow sizing based on zone requirements
  • Accurate sky illumination model for daylighting calculations
  • Ability to read multiple interval per hour weather data files
  • Plenums
  • Enhanced calculation of return air heat gain from lights
  • Flat plate exhaust air heat recovery
  • Automated creation of EnergyPlus geometry input from CAD files
  • Example heating, ventilating, and air-conditioning system and equipment input templates
  • User-customizable reports
  • Atmospheric pollution calculation

The EnergyPlus simulation program reads and writes output as text files. Its input and output data structure is designed to allow easy development of third-party interfaces such as the 15 already available for DOE-2. Most users will use graphical user interfaces when these tools become available later this year. The program was created primarily for use in Windows; but adaptations for Linux and UNIX are available.

Release No. R-01-050