The use of air conditioning for an aircraft during its turnaround is necessary whether on a warm or sunny day, or in cold ambient conditions as the cabin would otherwise become quickly uncomfortable.

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To achieve this, when no appropriate facilities are available on the ground, the aircraft will use its on-board APU (Auxiliary Power Unit) which is a jet turbine fed from the main aircraft fuel tanks primarily used in flight for example in case of a main engine failure.

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Using the APU on the ground is a last resort solution being uneconomical for the airline and an aggression against the environment as this jet engine has an overall energy efficiency of only 4%! Simultaneously, large amounts of air contaminants are emitted. Among these the CO2, creating a Greenhouse effect in the Earth’s atmosphere, as well as NOx and small particles which directly affect our daily lives.

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Running the APU on the ground is very expensive for the Airline; for example, a Narrow Body aircraft consumes about 100 kg/hour of Jet Fuel to which must be added the cost of maintenance for APU. A ground-based Pre-Conditioned Air (PCA) system offers an attractive alternative. Being powered by electricity from the grid, the PCA unit will dramatically reduce the on-site emissions and noise pollution. As a rule of thumb, let’s consider that a single narrow-body aircraft running its APU during one hour every day produce more than 100 tons of CO2 in one year.