I have stumbled upon an interesting stats while reading Rational Optimist by Matt Ridley. Lighting folks could make good use of it. Mind it was written in 2010!
Ridley poses a question how much artificial light one can earn with an hour work.
- Sesame-oil lamp in 1750 BC: more than fifty hours of work
- Tallow candle in eighteen hundreds: around 6 hours
- Kerosene lamp in 1880: 15 minutes
- Incandescent lamp in 1950: 8 seconds
- Fluorescent lamp on the brink of the first decade of the new millennium: half a second
“From six hours to half a second – a 43,200-fold improvement – for an hour of lighting: that is how much better off you are than your ancestor was in 1800, using the currency that counts, your time,” says the author.