By Kim Robson:
Darkness does good things for our health and psyches. In fact, medical research shows that excessive light causes a variety of adverse health effects. Many lighting design textbooks use human health as an explicit criterion for proper interior lighting. Over-illumination and improper types of light can compromise health, resulting in headaches, fatigue, stress, decrease in sexual function, and increase in anxiety. Lab animals exposed to unavoidable light have shown negative effects on mood and anxiety. Exposure to constant bright light is considered a very simple and effective torture technique.
In “Blinded by the Light?” (2009), Professor Steven Lockley of Harvard Medical School states that the human health implications of light pollution are great, and that “light intrusion, even if dim, is likely to have measurable effects on sleep disruption and melatonin suppression. Even if these effects are relatively small from night to night, continuous chronic circadian, sleep, and hormonal disruption may have longer-term health risks.”
We can reduce light pollution and our environmental footprint by simply turning off unneeded lights. For instance, we
should be lighting up stadiums only when there are people inside them. Participating in World Lights Out events, which encourage public buildings and bridges to turn off their decorative lights for one hour, is a nice thought; but instead of practicing Lights Out only once a year – and only for one hour – why aren’t we doing it every night?
Turning off a few lights is a great start, but let’s explore other ways we can reduce our electricity consumption. In our technology-driven world, rarely a day, or even an hour, passes without using some electronic device, whether it’s a smart phone, tablet, laptop or desktop computer.
A significant portion of the population never turns these devices off, preferring to leave them in “sleep” mode, in which they are still drawing energy. The same applies to device chargers. You know how all chargers have a little black box attached to the plug end? That little black box is a capacitor, which is a mini electrical storehouse. Left plugged in at all times, chargers are constantly drawing power, even if the device isn’t charging or plugged in.
There are countless appliances that pull this sort of “ghost draw,” using electricity even when the thing seems to be turned off. All those little red lights on televisions, radios, tablets, speakers, telephones, etc. are showing there’s a capacitor ready and waiting to make your device spring to life at a moment’s notice. Appliances with clocks, like the microwave or coffeemaker, also draw power constantly, even when turned off.
Unplug all your devices and appliances with a ghost draw (most everything has one nowadays), and you could reduce your carbon emissions by about 274 kilograms a year. Annually, U.S. households spend $100 a year on average for gadgets that aren’t even being used. Idle devices and appliances use 100 KW of power a year, enough to power 8.7 million houses, costing consumers about $11 billion.
All of humanity uses approximately 62,000 terajoules of energy, spending $2.68 billion per hour. By comparison, the atomic bomb that exploded over Hiroshima released about 63 terajoules. If we had an Earth Hour every day and used that saved money to fund sources of renewable energy, we could build two solar arrays, 30 geothermal generators, four tidal generators, 37 wind turbines, 102 wave energy converters, or six hydroelectric dams. That’s for ONE HOUR.
If we did that every day, we could build enough renewable energy to meet global electricity demand in just eight months and 10 days. Suddenly, Earth Hour doesn’t sound so irrelevant and silly, does it?