Thanks to Mr. Pierre Robillard, P. Eng., Quality Assurance and Training (electricity) Director with Kelvin-Emtech.

From the book “Vert paradoxe : le piège des solutions éco-énergétiques” by David Owen:

vert-paradoxeA Yale University economist, Mr. William D. Nordhaus, analyzed the cost of lighting throughout history and calculated as follows:

–          58 hours of work were required to the Paleolithic era to have a fire providing 1000 lumens-hour

–          In the ancient Babylon, more than 41 hours were needed to get enough oil lamp to produce 1000 lumens-hour

–          A contemporary of Thomas Jefferson had to work about 5 hours and 20 minutes to get the same amount of light from candles

–          1000 lumens-hour is the light emitted by a 75W incandescent bulb in less than an hour

–          In 1992, the average American achieves the same result with a CFL in the equivalent of less than a half second …

The author of the book concludes:

“lncreasing the energy efficiency of illumination is nothing new[…]. Yet our efficiency gains haven’t reduced the energy we expend on illumination or shrunk our energy consumption over all. On the contrary, we now generate light so extravagantly that darkness itself is spoken of as an endangered natural resource.”