Energy efficient and environmentally friendly system solutions come to the fore. The indicators of expected system solutions are less emission, lower noise, and decreased carbon footprint as well as increased energy efficiency. In this study, air-conditioning requirement of the aircraft in the park position has been discussed and different application systems have been examined comparatively with reference to the cooling load values at different times of the day. Besides, recirculating mixed air ventilation systems and pre-conditioned air systems added with and without phase change materials (PCMs) have been examined. For the air conditioning of a parked aircraft, pre-conditioned air systems instead of auxiliary power units (APU) are sure to stand out in any case, and starting from the best, these systems are with phase change material, floating condensation system, and direct expansion systems. In addition, the installation of vertical-axis wind turbines in the energy supply system based on wind energy, which is a renewable energy source, was examined in the context of efficiency.