NOVELTY - The method involves operating a number of spaced apart intrusion detection solar towers (120), where each tower includes a solar panel (30) and a detection equipment. An electric power is provided to operate the detection equipment of each tower with the respective solar panel to define an intrusion detection zone (Z). A signal is wirelessly transmitted from one of the towers to a processing unit (141) by relaying the signal among other towers, where the processing unit is outside communication range of one of the towers and within communication range of the other towers.    USE - Method for detecting an intruder e.g. person, in a solar powered perimeter beam security system i.e. supervised-wireless perimeter security detection system, for outdoor application. Can also be used for detecting a vehicle such as watercraft and an outboard boat engine, at a boat dock in water application.    ADVANTAGE - The method enables utilizing a solar panel mounted to one of the towers to provide local power, thus eliminating the need for supplying power from a remote source. The method enables utilizing a point-to-point multi-level quad-beam having a range of 600-800 feet with respect to the tower, where four beam paths are simultaneously broken to activate an alarm, thus reducing false alarms when birds and dogs pass through the beam. The towers can be deployed relative to communicating ranges to assure that specific towers are within range of the desired tower to reduce chance of communication disruption from a single point tower failure.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a system for detecting an intruder.    DESCRIPTION OF DRAWING(S) - The drawing shows a perspective view and a schematic view of a solar powered perimeter beam security system employing a set of solar towers, for emitting a detection beam, and a remote central unit.    Intrusion detection zone (Z)    Solar powered perimeter beam apparatus (10)    Solar panel (30)    Spaced apart intrusion detection solar towers (120)    Processing unit (141)