The price of lighting has dropped over 99.9% since 1700

In the last two centuries, the price of lighting has decreased drastically.

You can see this in the chart, which plots historical data from Roger Fouquet and Peter Pearson. To allow for comparisons over time, the data is adjusted for inflation and expressed in prices for the year 2000.

In the 1300s, one million lumen-hours — a standard lighting measure — would have cost around £40,800 in 2000 prices. By 2006, this had fallen to £2.90, a 14,000-fold decline.

Innovations in lighting appliances, fuels, infrastructures, and institutions during the 19th and 20th centuries made this progress possible.

To put this in perspective, consider that a standard 100-watt incandescent light bulb today can emit about 1,700 lumens. Therefore, running one such bulb for 24 hours would produce about 50,000 lumen-hours. That means that 1 million lumen-hours today would require continuously keeping a standard 100-watt incandescent bulb on for about 25 days. Achieving the same amount of light with candles would require burning more than 100 candles every day for that period.

Most people today take the ability to switch on a light at night for granted. But those who live or have lived without artificial light can appreciate how important it is.

Read more on our page on light at night →