Measure Savings Calculations

OptiMiser has two methods for calculating savings of measures in a package. One method is order agnostic, meaning no priority is given to any measure when applying interactive effects. The second forces the measures to be applied in order of SIR.

Order Agnostic:

• All measures are applied and the total consumption levels of the improved home are compared to base home to establish the savings of the package.
• For each measure in a selected package, we calculate the change in package savings incurred by removing that measure from the package.
• We then normalize these numbers to the total package savings. In other words we apportion the total package savings based on the impact that each measure has on the total package.
• This is the default method for most versions of OptiMiser
• This method can lead to confusing results when fuel switching measures are included in the package.

Ordered by SIR

• Each measure is added to the package sequentially in order of SIR
• When each measure is added we save the new improved building consumption and compare it to the consumption saved in the previous step.
• The consumption difference is calculated for each step to establish the savings for the added measure.
• This method is required for DOE sponsored weatherization programs.
• This method generates more intuitive results when fuel switching measures are included in the package.