The Unique Characteristics of a Ground Power Unit

Ground power units pack quite a powerful punch for its size.

What Are GPU’s?

A ground power unit, or GPU, is used to provide electrical power and air conditioning to airplanes while they are on the ground. Smaller airports will have GPU systems built into a cart while larger airports have GPU’s that are built into the pavement.

Ground power units have an internal diesel engine that can generate either a 24 volt power supply or 28 volt power supply.

During midflight, planes will use their auxiliary power unit, or APU, for air conditioning and electrical purposes. Once landed, ground power units are preferable because of their massive power output.


While you may believe that a GPU is just a grounded version of an onboard APU, there are plenty of reasons why airports continue to rely on GPU’s. For one, GPU’s do not require any of the aircraft’s kerosene. Additionally, APU’s burn jet fuel while GPU’s burn diesel – which is in fact cheaper. Also, when you factor in the maintenance of an APU versus a GPU, ground power ends up being more cost-efficient.

APU’s also need to be approved by the FAA or government authorities, which not only takes time but is an incredibly expensive process to go through – not to mention time-consuming. Ground power units operate just as effectively and tend to save airports and users a significant amount of money and headaches.

Ground power units that are built into airports are much quieter than auxiliary power unit. In Europe noise factor has been such a pressing issue that it became a requirement for APU’s to be initiated minutes prior to them leaving the runway.


Start Pac is a supplier of reliable ground power units. If you’re in need of an efficient, high quality 28 volt battery pack for your aircraft, visit Start Pac online today.