Determination of the LEP Beam Energy using Z Recoil Events

The precise knowledge of the beam energy, E_beam, at the LEP collider is important to reduce the systematic uncertainty on the W mass. The measurements by the LEP energy group can be cross checked using Z recoil events. Preliminary results of the four LEP experiments ALEPH, DELPHI, L3, and OPAL are presented. The combination of the results shows no significant deviation of the E_beam value obtained using Z recoil events from the measurement by the LEP energy group.