Among the growing number of research resources available through the DOE’s Building America program, Building Energy Optimization software—or BEopt as it’s known—developed in 2006 by the National Renewable Energy Laboratory (NREL) continues to provide analytical solutions from a wide range of parameters that now include existing homes. Architects and engineers using BEopt for new homes have been able to explore optimal pathways to zero net energy for their projects by inputting building geometry, energy sources including PVs, economic parameters including mortgage rates and energy source costs, and a variety of energy-saving features.
Once entered, these parameters produce an output screen displaying comparative results for optimal designs, including graphs that show the path to net zero, end-use results, and option costs. And you can choose to have energy-savings calculations compared with a base-case building you define or a climate-specific Building America Benchmark building.
The new version, which was released in January by NREL, extends BEopt’s capabilities to analyze existing buildings, including simulation-based analysis and optimization using specific house characteristics and locations. According to NREL, the new version allows modeling of a wide range of energy-efficiency upgrades and their corresponding retrofit costs, including removal, disposal, and re-installation. The program also includes a factor for downsizing HVAC equipment when that is within the scope of a project. In addition, BEopt’s economic calculations take into account degradation factors for remaining equipment and incorporates a minimum upgrade scenario for future equipment replacements.
With 116 million existing homes in the United States and a lingering downturn in new-home sales, analytical tools like BEopt can help substantiate recommended energy-efficiency measures for remodeling projects and transform the existing housing stock from the vast energy wasteland it is today into a vast and virtual source of energy.
You can learn more about the features and functions of BEopt and download the software at http://beopt.nrel.gov.