A revolution is upsetting the lighting business as LED lightbulbs replace energy-hogging incandescent ones. This is good news for consumers and the environment; using less energy reduces the greenhouse gases that contribute to climate change.
But this shift comes with a cost, exemplified by a century-old lightbulb factory in St. Marys, Pa., that is the latest to shut down.
For much of its long history the LEDVANCE facility, 120 miles northeast of Pittsburgh, produced lightbulbs under the Sylvania brand. Now all it produces is scrap metal.
Times change and so do technology. The truth is the modern light-bulb is far more sophisticated then those outdated technologies, and China built the factories to make the inexpensive advanced, highly-efficent switch-mode power supplies and LED panels that make the modern bulbs much more affordable -- rather then the United States. But as technologies advance, it really is a win for most Americans, even if the old technology manufacturers are left behind.
This is a very interesting video about street lighting.
It turns out humans (and most animals) have a lot of trouble seeing yellow light after dark, which means that much of supposed efficiency of high pressure sodium lights is wasted. Colder light colors, like that of the mostly obsolete mercury vapor lights of 1950s and 1960s, and modern LED bulb are better at lighting up a street with less actual light output. As the video notes, is some evidence today they made a mistake in 1970s ripping out mercury vapors lights in favor of the more "higher laboratory light output per watt" high pressure sodium.
LEDs can be made any color you want based on the phosphorous. Cold white is popular because you can use a dimmer light while it appears brighter to human and animal eyes. Warm white is less disruptive to sleep and wildlife, more pleasant to the eye, and with less light pollution (in theory) but it's harder humans to see. One interesting idea proposed in the video would be to have street lights start out at a lower-output cold white color in the early evening, and switch to a higher-output warm white color in the early hours of the morning, when fewer people are in the street but you don't to disrupt sleep as much.
Another interesting idea from the comments in the video would be to use high pressure lamps (or warm white LED bulbs) in residential neighborhoods, while using well aimed cold white LED in commercial areas, on highways, and other "high crash areas" such as city centers where there many pedestrians crossing the streets. Mixing warm white and cold white strategically could work to further warn drivers -- suddenly transitioning from a warm white color to cold white color could warn the driver that they are entering a "high crash area" and to use extra care proceeding through that area.
What are the differences between different waterproofing rates on LEDs and other products?
Learning about the different types of RGB LED products that are out there.
And I was impressed by the 400 watt light bulbs they used to have at SUNY Plattsburgh in the Conference Rooms. Even with Albany's pricey residential electricity, this light bulb would only set you back $3 an hour to operate -- assuming you had 166 amp line at 120 volts or 83 amp at 240 volts.