What's the true cost of artificial light?
Instead of comparing values in terms of money in one currency or another, this article uses manual labour - measured in terms of time - to determine what producing light after sunset has cost over time.
The Greeks and Romans used wax candles and Nordhaus estimated that a typical wax candle, putting out 13 lumens, required five hours of labour to generate 1000 lumen-hours, but in our day, it costs less than half a second of labour to produce the same amount of light.
