A good solar street light can be evaluated from several aspects:

1. Luminous efficacy (lm/W) – High efficacy = better efficiency
   
2. Illumination coverage – Uniform lighting without dark spots
   
3. Battery quality – Long lifespan, stable capacity, and rainy-day backup
   
4. Control system – Smart sensors, timers, remote control capability
   
5. IP Rating – Minimum IP65 recommended
   
6. Design structure – Wind resistance, good heat dissipation, and easy installation