ENERGY MODELING
Energy performance modeling is easy to understand in terms of cars. An automobile manufacturer tests a car under a prescribed method to determine its Miles per Gallon (MPG). When an owner drives a car and calculates their own MPG, it does not match what the manufacturer stated because of roadway complexities and human preferences. Variables like this also occur in a house.
Energy performance modeling is a comparative tool giving architects and engineers analytical data to assist in making informed choices in energy efficient building design. Energy performance modeling does not accurately predict the real life energy consumption of a building or house because energy consumption is also affected by the occupants (home owner and family). The modeling does predict the performance of the house based on the assumed operational behavior, as established by the California Energy Commission, of the home owner and family.
The human factors aspect of energy efficiency is as critical as the design/construction of the building, and this is why a HERS ll Rating (Whole House Energy Rating) also includes an educational process for the home owners.