In one of his farm journals, Thomas Jefferson displays the importance of the sun. Just because the length of the workday is determined by daylight, one half more wool was spun during July than in January .
You can start to see how everywhere in colonial Virginia, sunlight made a huge difference. Building a house? Your windows will probably face east and west. But even then, you need to be sure than no tree or house blocks the sun or creates a shadow. As for painting, absorbing rather than reflecting light, dark colors should be avoided. And, if you work at home you will need lots of bright light if you are a printer and diffused light if engraving is your trade. Why not use candles? Sunlight is free.
There even was a formula that used room volume to calculate how many square feet of windows you needed. For example, if the volume of a room (l x w x h) were 64 square feet, then you take the square root of 64 and can assume that 8 square feet of windows will bring in the most light.
Fast forward to contemporary sub-Saharan Africa.
President Obama’s $7 billion “Power Africa” public/private initiative is targeting a region where two thirds of the people lack electricity. Enabling villagers to avoid the wait for a national grid, private solar panel firms have begun potentially profitable solar panel experiments. One village that recently was given small solar panels for each home is using them to power batteries. Used in 2 LED ceiling lamps and a lantern, the batteries eliminated the need for kerosene and transformed everyday life.
A Solar Panel in An African Village
Our bottom line: Whether looking at the colonial US or contemporary Africa, the sun affects the productivity of land, labor and capital.
Sources and resources: Describing how candlelight and sunlight affected colonial Virginia, this article conveyed details from everyday life. It also presented insight that applies to the contemporary sub-Saharan Africa’s electrification initiatives, described here and here and in this 289 page World Bank document. For more on African electrification, econlife looked at the impact of new street lamps in Lagos.