Building Energy Modeling

Building Energy Modeling

Building Energy Modeling allows estimation of annual building energy consumption, both zone-wise and end-use component-wise data. Such energy analysis is a requirement for USGBC LEED® rating systems, MA Stretch Code, IRS Tax Incentives per IRS Notice 2006-52 and 2008-40, etc.

GRT staff performs in-depth building energy modeling using project specifications, if available, or helps achieve optimized building thermal specifications through a process-oriented NZE approach. The building energy modeling process includes,

• Compiling take–offs and modeling assumptions
• Determining schedules of operation for various occupancies
• Defining equipment power densities, air changes per hour, light power density, occupant density
• Determining window-wall-ratio, floor-to-floor heights, plenum height, Solar Heat Gain Coefficient and U-factors for fenestration, etc.
• Identification of various alternatives Energy Conservation Measures (ECMs).
• Prioritizing ECMs based on the resultant saving. Eventually, all ECMs that yield satisfactory results of reasonable payback period will be combined into a single case. Several configurations of Base Case + ECMs need to be defined and simulated before arriving at the best or optimum combination of ECMs.
• Reporting energy analysis calculations that will include a description of the project, a record of all modeling assumptions (set-points, material specifications, schedules, equipment and lighting densities, etc.), a description of ECMs, recommendations, specifications, and simulation results.

While developing the model, certain approximations are necessary such as, simplification of complicated contours and using thermal properties of the most closely related material for new or unspecified building materials. Attempts, though, would be made to minimize such compromises.