Replacement decision in brief
Pneumatic transfer can change maintenance tasks while increasing the importance of the compressed-air system. Compare measured or justified air demand over complete cycles at the required supply pressure, including treatment and distribution losses. Evaluate both average and peak demand. A maintenance benefit must not be presented as an automatic energy saving.
Use the plant energy boundary
A pneumatic skid may have a small local electrical connection while its driving energy is supplied by a remote compressor. Include that compressor energy and relevant auxiliaries in the cost comparison. For a mechanical pump, include the motor, drive and any required seal-support or heating equipment on a comparable basis.
Build an auditable calculation
A useful screening method multiplies measured or agreed air use by the plant specific energy consumption and electricity tariff. For illustration only, 120 reference m³/h × 0.11 kWh per reference m³ × 6,000 h/year × 0.10 currency units/kWh gives 7,920 currency units/year. The assumed numbers are not a performance statement; replace them with the actual plant basis.
Check part-load and pressure effects
Compressor efficiency can change with operating pattern and control mode. A plant-wide average may not represent the incremental cost of a new intermittent load. Distribution losses and unnecessarily high pressure also influence cost. Ask the utility team whether spare air capacity is available and whether expansion would require new capital equipment.
Keep the other costs visible
Energy may be higher or lower than another transfer method for the particular duty. Maintenance, product loss, downtime, cleaning and installation can still change the business case. Show these items separately and test uncertain assumptions. A transparent total-cost comparison is more credible than a universal savings percentage and lets the buyer see which variables drive the decision.
General engineering guidance. Numerical examples are illustrative; project specifications and acceptance criteria are agreed for the actual duty.