The map shows the geographical distribution of
the solar radiation incident on the earth's surface
each year. Depending on the shape of the sun's apparent
path (solar ecliptic), the amount of radiation decreases
towards the polar regions.
On the land area worldwide, this results in a solar
radiation of at least 200,000,000 TWh per year.
(For comparison: 9 billion people, each requiring
2,000 watts, would have a total annual energy demand
of 160,000 TWh.)