There are a variety of outdoor areas that require nighttime lighting. While choosing the outdooor LED lights for your space, considering the wattage is not enough to judge the brightness. Besides wattage, you should also know about how many lumens you need for outdoor lighting. In the following passage, you can learn about the relation of wattage, lumens, and brightness, as well as the recommended lumens for various applications.
Wattage, lumens, and brightness
Electromagnetic waves are the form that the light source emits energy in. Joules (J) are used to measure this energy, and it is known as radiant energy. Radiant flux is the amount of radiant energy that a light source emits every second; it is measured in watts (W). The higher the radiant flux of a light source, the brighter it seems to the human eye. Nonetheless, the brightness of two light sources with the same radiant flux differs if they produce light waves at different wavelengths. The light with higher luminous efficiency looks brighter. Thus, luminous flux—which is measured in lumens (lm), the product of radiant flux and luminous efficiency—is what actually influences how bright the light is.
“While the parameter of watt is on the light bulb packages for decades and is familiar to consumers, it measures energy consumption instead of brightness,” the FTC clarified in a press release. “As a result, relying solely on watt makes it difficult for consumers to distinguish which lights are brighter.” The U.S. Federal Trade Commission has required manufacturers of CFL lamps, incandescent lamps and LED light bulbs to use lumens to indicate the brightness of light bulbs.
Below is a lumen to watt conversion table for different light sources:
| Lumens | Incandescent | HID | CFL | LED |
| 250 lm | 25 W | 18 W | 6 W | 2-3 W |
| 560 lm | 40 W | 29 W | 10 W | 3-6 W |
| 800 lm | 60 W | 43 W | 13 W | 7-10 W |
| 1100 lm | 75 W | 53 W | 18 W | 10-15 W |
| 1600 lm | 100 W | 72 W | 23 W | 15-20 W |
| 2600 lm | 150 W | 100 W | 42 W | 20-30 W |
What are the lumens of different outdoor lights?
- Street lights: Street lights play the role of illuminating main streets, so the lighting requirements are high and may vary according to different road types. The required lumen can range from 3000 to 15000 lm. For wide roads with multiple lanes, large square, and other places that covers a large area, they need super bright LED street lights.
- Decorative street lights: The street lights in residential areas are usually 3 to 5-meter-high, and they can only illuminate a relatively small area. They guarantee inhabitants’ safety and offer lighting for their nighttime activities. Besides, they can have various styles and decorate the outdoor spaces. Therefore, the lumen requirements are not too high. Their light can be 3000 lm and the LED lights they use are 30-50 W.
- Lawn lights: Lawn lights have high luminous efficiency and emit uniform light. Mostly for decorative purposes, they are utilized as road lighting in parks, private gardens, neighborhoods, courtyards, hallways, and other public locations. Common lumen requirement for lawn lights is between 300 and 1000 lm.
- Underground lights: The wattage of LED underground lights is small, which can be 2-20 W. They can be the decorative lighting for park lawns, squares, courtyards, flower beds, and fountains. The lumen of these lights is about 50-500 lm.
- Spotlight: Spotlights can be used to highlight the decoration of a certain place, and can also increase the three-dimensional effect and create a special atmosphere. The light is quite concentrated and not very bright. The lumen of the spotlights is about 500-1500.
- Flood lights: Outdoor flood lights are high-power lights and have many functions, such as lighting up buildings and creating wall washing lighting effect, working as security lights, etc. The light of flood lights diffuse and can illuminate a large area. This light can be 1000-2000 lm bright.
Frequently asked questions
- How bright is 4000 lumens outdoor?
4000 lumens is equivalent to the brightness of four 10W LED bulbs. Similar to the visual experience brought by 30-40 W LED car lights. Looking straight at the light will cause you to feel a little dazzling.
- How much area will 3000 lumens light up?
To know the specific illumination area, you need to consider the illumination requirements of different spaces. For example, to achieve 200 lx garden lighting, 3000 lm lighting can light up 15 square meters.
- What light is best for outdoor lights?
LED lights are the best choice for outdoor lights because their efficiency keep improving, which means they can save a lot of energy. What’s more, they usually have high IP rating to resist the rain and emit little heat to keep cool under high temperature.
To wrap up
Knowing that lumen is more accurate than wattage while judging brightness is important when choosing outdoor lights. Outdoor lights include street lights, decorative lights, lawn lights, underground lights, spotlights, flood lights, and so on. Since they are used in different places to create various kinds of lighting, the lumen requirements are different. If you want to ask more about the lumen standards for other types of lights, you can contact with our experts right now!
