Energy Modeling Software: Benefits & Drawbacks

People are becoming more familiar with energy modeling software. These programs predict energy consumption of homes, and they are more widely seen due to the popularity of energy audits that seek answers on how to reduce energy consumption for homeowners. Whether or not these software tools are worth the time and expense for a construction project is going to depend on the circumstances.

Energy modeling programs serve different purposes. Some are commissioned by manufacturers or industry organizations to help market their equipment. Others are specific to the green building industry, or have a narrower niche market like those catering to net zero home design. There are specific programs developed as tools for states or municipalities to ensure code compliance by calculating the energy efficiency during the design phase, and still others for energy audits and retrofitting during remodeling.

In general energy modeling involves plugging in different variables to determine if, for example, a window upgrade or a different insulation product will be the most effective at energy savings. Then you can decide where your investment is best made. The more time consuming the program is to use, the more variables it will cover and the more accurate the calculations should be. The downside of this is that the models that cover a lot of different factors often ask for details that can't be easily measured, leaving a lot of guesswork that can be a drain on accuracy.

Another weakness in energy modeling software tools is that when they are in the hands of someone who stands to benefit by up-selling materials, you don't know if you can depend on the accuracy of the figures being input. It is common for the quality of the existing construction to be underestimated. Worst-case conditions are typically assumed, when those may exist only on rare occasions. Many programs also have systematic failures where the complexity of home design simply cannot account for the calculations in a straight-forward spreadsheet formula.

What these programs do very well is calculate for new construction, where there is far less uncertainty in measuring quality and reliability. When the guesswork is minimized, energy modeling tools can do a great job of determining energy efficiency in a home without being overly complicated. At this time, you are likely to do best for a remodeling projects by making educated assumptions and choosing wisely to improve on the things you know are typically problematic in the type of home you own.