A New Version...
U.S. Department of Energy Releases EnergyPlus Modeling Software
The U.S. Department of Energy released the latest version of its building energy modeling software EnergyPlus, which calculates the energy required to heat, cool, ventilate and light a building.
EnergyPlus is used by architects and engineers to design more efficient buildings, by researchers to investigate new building and system designs, and by policymakers to develop energy codes and standards. The advanced physics calculations within EnergyPlus allows it to model a wide range of residential and commercial buildings and heating, ventilation and air conditioning system types, including passive building designs and low-energy systems. EnergyPlus v7.0 features many enhancements including: 
- 25 percent-40 percent faster execution speeds on a wide variety of models. Up to 500 percent improvements are possible on models using airflow networks
- Improved modeling of ventilation rate procedures and a new thermal comfort report, both based on ASHRAE Standard 62.1
- New equipment performance data sets for packaged rooftop air-conditioners and heat pumps
- New model for variable refrigerant flow heat pump air-conditioners
- Extensions to the Energy Management System and Runtime Language
- Updated utilities.
EnergyPlus v7.0 is available free of charge for Windows, Mac OS, and Linux. Source code licenses are available, too. View the full list of enhancements, or download the latest version.