The one whinge of the Tea Party I share is their objection to being forced to swap incandescent light bulbs for high-efficiency fluorescent ones.
Horrid things. In small part itâ€™s the snake oil about longevity â€“ the claimed 10,000 hours or whatever only holds if you never turn them off, as my generation were brought up to do. (Last one out turns off the lights. Whatâ€™s the new rule to teach your children? Multifactorial optimisation on the go?) Another thing is the propagandist refusal to take a systems approach â€“ waste heat is space heating, which we need anyway in northern latitudes, though not of course in the tropics. Partly itâ€™s the clunky form factor; the bulky ballast means that they donâ€™t fit properly into older light fittings. Mainly however itâ€™s the unpleasant colour spectrum.
Lighting engineers think we should be happy with fluorescent lighting because itâ€™s approximately the same colour temperature as daylight. The sunâ€™s photosphere is as near as dammit a black-body radiator at 5,800K, and thatâ€™s what we get minus the ozone-filtered UV. (Mercifully we are not exposed to the radiation of the fusion furnace at the core at 13 million K.) The mean equivalent temperature of fluo lamps is 5,500 K, very close, though as they arenâ€™t black-body radiators there are spikes in the blue and green and the overall effect is hotter (psychologically: cooler and nastier).
Spectral power distributions compared. Horizontal units are wavelengths in nanometers. The shorter tail of the incandescent bulb’s distribution is truncated because it lies in the invisible infra-red.
But who said artificial daylight? What we want is firelight. The light of flames is an envelope of black-body radiation from carbon (soot) particles at various temperatures, averaging 1,700K or so. Candlelight is 1,850K. An incandescent tungsten-filament light bulb is a nearly pure black-body radiator; temperature depends on rating, but 2,700K is typical. (Source for data and image: Wikipedia.) So tungsten light bulbs are much closer to firelight than fluo lamps are, and thatâ€™s why we like them. A plea to the designers of LED lamps, the real long-term solution to low-carbon lighting, which start with three colours of monochromatic laser light: if you can, give us back our candlelight.
You could write an ev. psych. “just so” story about our deep-rooted preference for firelight. Hominids have controlled fire for at least 400,000 years – long before the emergence of modern homo sapiens a mere 100,000 years ago; we shared fire with homo erectus and Neanderthals. The same probably goes for gatherings of the hunter-gatherer band around the fire at nightfall. Over the millennia many matings must have been arranged around such fires, before sneaking off together into the dark. Disliking fire and firelight would be maladaptive; liking it, and looking good under it, adaptive, nuh?
Weeell. Not a strong story. Fire itself is a bombproof human cultural universal – surely there’s no gene for it -, and it has built up a whole raft of positive cultural associations, including warmth, food, music and storytelling. Sex too of course: the reddish light makes skin of all ages look younger and healthier, ergo more attractive. Restaurants catering to the dating market go for candles.
Everybody loves a candle. My parents used to put real ones on the Christmas tree: a bit exciting, and the soda siphon was kept handy. We could only light up once or twice for half an hour. But there was a hushed magic electric lights donâ€™t begin to match.
Recently candlelit vigils have been taken up as a form of non-violent protest or commemoration. The fragile candlelight builds community and disarms hostility. Hereâ€™s a mass protest in Seoul against the threat of mad cow disease from evil beef imports from the USA; pacific and civilised doesnâ€™t necessarily mean sensible. Source here.
For millennia, candles and oil lamps have been an important part of the rituals of many religions: Buddhism, Christianity, Confucianism, Hinduism, Judaism, Shinto, Sikhism, not to mention Wicca and Kwanzaa. Zoroastrianism is all about fire. Official Islam is the odd man out: it gives no ritual place to candles, but they are sold to pilgrims at the not-quite-kosher tombs of marabouts in Morocco.
Let me give the last seasonable word to (allegedly) Confucius:
It is better to light one small candle than to curse the darkness.