In the context of increasingly pressing global energy issues, the lighting energy efficiency of large urban parking lots is gradually becoming a focal point of interest in building energy conservation. This study delves into energy-conserving approaches for parking garage illumination, specifically examining traditional, sensor-based, and parking space allocation methods. In sensor-based mode, the lights turn on when a vehicle arrives in the parking lot. In allocation mode, a target parking spot is assigned to the vehicle, and the lights along its path are illuminated. Through simulation experiments conducted on a prototypical garage, it is found that sensor-based and parking space allocation modes exhibit superior energy efficiency compared to the traditional mode, while maintaining functionality. These findings suggest the potential for wider adoption of these advanced strategies.