The cost calculation depends on the selected utility type. For the compressed air utility type, annual cost is the product of consumption and the cost rate per unit volume. For the electricity utility type, annual cost is the product of the electrical energy use and the electricity cost rate.

Compressed Air Utility

\begin{equation}\label{eq:compressed-air-reduction-cost-air} C_{cost} = r_{air} \cdot C\end{equation}

Electricity Utility

\begin{equation}\label{eq:compressed-air-reduction-cost-electricity} C_{cost} = r_{elec} \cdot E\end{equation}

Symbols

\(C_{cost}\)	Annual energy cost \([\unit{ \dollar\per\year}]\)
\(r_{air}\)	Compressed air cost rate \([\unit{ \dollar\per\cubic\foot}]\)
\(C\)	Annual compressed air consumption \([\unit{ \cubic\foot\per\year}]\)
\(r_{elec}\)	Electricity cost rate \([\unit{ \dollar\per\kilo\watt\hour}]\)
\(E\)	Annual electrical energy use \([\unit{ \kilo\watt\hour\per\year}]\)