With the spread of solar street lights, there are now many lighting levels to consider. One of those arguments is wattage and flow, as well as determining brightness. The old way to check how bright a light is is to check the number of beads. For incandescent lamps, the higher the wattage of the lamp, the brighter it will be. Now we need to pay attention to the lumens of the lamp to determine the brightness of the lamp, especially when it comes to solar street lights.

What does wattage mean? The wattage of light is the energy required to produce a certain amount of light. The higher the wattage, the brighter the light, but the more power. Incandescent lamps introduce the efficiency of the system.

E.g:

A 40 watt incandescent lamp produces only 380-460 lumens and consumes 40 watts per hour.

A 100 watt incandescent lamp produces 1700 – 1800 lumens and consumes 100 watts of energy per hour.

 Direct sunlight is about 100k lumens and consumes no energy per hour.

This is an inefficient way of lighting and has seen many advances such as the introduction of fluorescent lamps, compact fluorescent lamps, metal halides, low pressure sodium and high pressure sodium. Fluorescent and compact fluorescent lamps produce better lighting with lower tile counts, but there are some environmental factors to consider. Metal halides, LPS and HPS produce better lighting than standard incandescent lamps; however, they typically have much higher wattages and use much higher power than their CFL or LED counterparts.

E.g:

40-watt incandescent lamps are now replaced by 9-watt CFLs or 4-watt LEDs

60-watt incandescent lamps are now replaced by 13-watt CFLs or 7-watt LEDs

100-watt incandescent lamps are now replaced by 32-watt CFLs or 15-watt LEDs

What does lumen mean?

Lumens are the light emitted by a certain lamp. If replacing a standard 150 watt bulb, emitting about 2600 lumens, using a 42 watt CFL or a 25 watt LED would be about the same. This reduces the required optical power to more than a quarter of the power required to produce the same light. A 70-watt LED fixture can produce 7000 lumens or more and replace most highway and parking lot lighting fixtures with more cost-effective lamps. This becomes more efficient every day.

Why is this important for solar street lights?

Solar street lights need to consider the flow and wattage of the lights. Wattage provides the required power from solar and battery systems, and the time it takes to power a solar street light. The flow determines the amount of light from the lamp. The higher the efficiency of the lamp or lamps, the higher the solar energy efficiency, the lower the cost of the overall system.

Solar street lights are generally lower off the ground and can then use lower wattage and higher lumen efficiency to produce more lighting. Most solar street lights use luminaires ranging from 20 watt LEDs to 90 watt LEDs (9000 lumens), and most applications typically range from 35 watts to 50 watts. Lighting levels require brighter lighting, with lower usage in residential and remote areas.