When it comes to technical terms used for solar lightin […]
When it comes to technical terms used for solar lighting, many may be confused at first. Industry-specific words are used which can make it hard to understand the advantages of one light over another. LED stands for Light Emitting Diode. They can use up to 90% less energy than traditional lighting and last up to 25 times longer (ref. US Dept. of Energy LED article below). When talking about Solar LED Lighting, there is a combination of two newer technologies that involve jargon from both industries. “Lumens” is a measure of the quantity of total visible light emitted by a source. This is the best way to measure how powerful a light is. To see how much energy it takes to create a given level of Lumens, Wattage is primarily used. Wattage is a measure of power comprised of AMPS X Volts. To understand the overall efficiency of a light relative to how much light it produces, Lumens per Watt is the industry standard. Soltech Smart Solar lighting provides 200 Lumens for every 1 Watt of stored sunlight, up to double the efficiency of many solar lights. It is this one of the performance breakthroughs that make our solar lighting a viable and realistic alternative to traditional lights on city streets, especially during sub-optimal sunlight conditions. Many municipalities have a minimum wattage requirement for lighting, but this measures consumption of energy, not performance relative to efficiency.
Color Temperatures Explained
The Kelvin Scale is another helpful unit of measurement when trying to understand light. Generally, the lower the Kelvin rating, the more yellow or warm the light appears. High Kelvin ratings appear as bright white light, but actually have more blue light in them. High Kelvin, less warm lighting is generally used in parking lots, street lights, & football stadiums. It appears more bright. Lower Kelvin ratings with a warmer color actually penetrate darkness further, can be less harsh to look at, can circumvent particles in the air (fog), and are more suitable for residential or marine applications. Some might ask, if yellow light penetrates darkness further, why isn’t the ocean yellow? In water, absorption is strong in the red and weak in the blue, thus red light is absorbed quickly in the ocean leaving blue. Red does not absorb as quickly as blue because blue is scattered more than other colors-it travels as shorter, smaller light waves. The higher the Kelvins, the more blue light is visible. The International Dark Sky Association officially recommends lights to be 3000 Kelvins or less. Some of the reasons they list include the harsh glare high Kelvin lighting can create, the suppression of natural melatonin production in the brain (part of the reason smartphones now have low Kelvin night modes), and the conservation of nightscapes/nocturnal wildlife. Some places, like southern Arizona, are aware of these factors, as well as others, and require all outdoor lights to be 3000 Kelvins or below.