Aero Savings Estimator

Methodology

How the estimate works

Choose your region (units and vehicle Cd table), set mileage and fuel consumption, then toggle devices on the current and proposed setups. Only the aero slice of the fuel pie changes with Cd.

• Region sets the vehicle

  UK and Europe use a cab-over artic (starting Cd 0.550). North America uses a conventional Class 8 (starting Cd 0.650), with matching ΔCd values.

• Duty cycle fuel pie

  A slider from highway to urban sets the share of each duty type — 100% highway on the left, 100% urban on the right. Between the ends, highway and urban always overlap, with regional strongest in the middle. The fuel energy pie in the results is the weighted blend of those shares (highway 50% aero; regional one third; urban one sixth).

• Devices change Cd

  Each fitted device subtracts its catalogue ΔCd. Fuel use scales with how much the aero component of the pie changes between the two setups.

• Annual fuel bill

  Editable annual mileage, fuel consumption and fuel price set the baseline bill that savings percentages apply to.

• Cost and payback

  Catalogue fitted costs feed net kit spend between setups. Payback and multi-year ROI appear when the proposed setup costs more and saves fuel.

• Before and after

  Left and right setups are independent. Add or remove devices on either side — including removing a device to see the fuel cost of not fitting it.