In Context

A list of quick facts about light.

It is estimated that at least 100 million birds are killed annually due to collisions with manmade structures, which include wind turbines, power lines, glass and towers. Collisions due to urban light represent approximately one third of all collisions, while two thirds of collisions occur during the daytime. 90,000 birds are killed flying into buildings in New York City alone. (American Bird Conservancy)

The lights of Las Vegas, Nevada, are visible from eight different national parks and are the dominant cause of light pollution in Death Valley National Park, 93 miles from the city. (Science News Online)

According to Energy Star, a U.S. Environmental Protection Agency and U.S. Department of Energy program, replacing a single incandescent bulb with a compact fluorescent light (CFL) bulb in every U.S. household would be the environmental equivalent of taking 800,000 cars off the road. (Energy Star)

About 63 percent of the world's population and 99 percent of the population in the European Union and United States (excluding Alaska and Hawaii) live in areas where the night sky is above the threshold set for polluted status. (Chepesuik, Ron. "Missing the Dark: Health Effects of Light Pollution." Environmental Health Perspectives, January 2009.)

The Phoebus cartel (1924-1939) was formed by light bulb manufacturers Osram, Philips, Tungsram and General Electric, among others. Manufacturers in the cartel not only fixed prices so that no manufacturer had to fear the competition of the others, but also secretly signed a commitment, pledging each other that light bulbs would be designed and constructed such that their expected life time would not exceed 1000 hours. (Glaubitz, John Paul Adrian, "Modern Consumerism and the Waste Problem.")

Glass building typology is responsible for the majority of bird deaths, two thirds of which occur in the daytime. The U.S. Green Building Council recently issued a new pilot project under the Leadership in Environment and Energy Design (LEED) program to reduce bird collisions with buildings that focuses on alterations to building materials, such as glazing. (U.S. Green Building Council)

Worldwide, 1.6 billion people do not have access to electricity (UNESCO. "Global Climate Change.")

LEED provides building owners and operators with a framework for identifying and implementing practical and measurable green buildings and reducing light pollution and light trespass. Nearly 9 billion square feet of building space participate in the LEED rating systems and 1.6 million feet are certified daily around the world.
(U.S. Green Building Council.)