In order to eliminate collision risk, GEO satellites should be moved out of the geostationary ring at the end of their mission. It is recommended that their orbit should be raised by about 300 km, which is considered a safe distance to avoid future interference with active GEO spacecraft. The change in velocity that is required to raise the orbit altitude by 300 km is 11 meter/sec, and the required propellant corresponds to that necessary for three months of station keeping. This means spacecraft operators have to stop operations three months before the spacecraft runs out of fuel and give up considerable revenue in order to reorbit their spacecraft. However, today, this is the only possibility for preserving the unique resource of the geostationary ring.