Courtesy: NASA and satellite SOHO.
|
Energy Sinks or
Sources |
J/year
|
TWh/year below M=millions G=billions |
Relative
Human Annual Consumption ("HAC") |
|
Total Human
Consumption of energy/year |
3*10E20 |
0,083 M = 83 000 |
1 |
|
Spontanious Global Photosynthesis/year |
3*10E21 |
0,83 M |
10 |
|
Total Incident Sun Energy on Tellus/ year |
5,7*10E24 |
1,58 G |
19 000 |
Approximately 5.7 x 1024 J of solar energy are irradiated to the earth's surface on an annual basis.
Plants and photosynthetic organisms frequently living and generating in harsh environment for regeneraqtion utilize this solar energy in the fixation of large amounts of CO2 (2x1011 t = 3x1021 J/year) with a C mass of ~120 Gt C in the biomass(containing a C amount of 44w%).
The total human consumption of energy is around 3 x 1020 J/year. This represents still only ~10% of the energy converted during photosynthesis.
Although large amounts of solar energy are irradiated to the earth's surface, the effective energy concentration (energy/unit area) of solar energy at any point on the earth's surface is small. Clear sunlight represent an effect per unit area of ~1 kW/m2 at most, even at noon. During 1 h this represents 1 kWh - a common unit on an invoice for electricity within EU, even if it is not a SI unit.
Such low effect per unit area has limit the use of solar energy as a primary energy source during the fossil C use era.
What a challenge in 2010:
Incident sun energy is still 17 000 bigger than total human consumption and photosynthesis is still 12 times bigger than human annual fossil C combustion.
In late 2009 the human consumption has raised to a level the annual sun incidence on the planet is "only" 17 000 times higher than total human consumption of energy.
The relation between human annual outlets of fossil energy seems to be around 9 Gt C during 2009, while the spontanious global photosynthesis seems to reach 120 Gt C in gross energy fixed. The annual plant respiration is 14 Gt C annually.
Annual Global Net Photosynthesis is therefore around 106 Gt C fixed.
In 2009 the global net annual photosynthetic (GNAP) fixation of C is therefore still around 11,8 times bigger than total human consumption of fossil C resources.
From a mass balance point of view photosynthesis is thereby the biggest process on the planet making the green plants to the real governors of the planet as we all know from primary school education.
Because the green plants create more exergy on the planet than any other organism they represent indeed the stoechiometric governors of Planet Earth.
Sources
FAO Corporate Document Repository in "Renewable biological systems for alternative sustainable energy production", FAO Agricultural Services Bulletin - 128, 1997
at http://www.fao.org/docrep/w7241e/w7241e06.htm#2.1.1 solar energy and frontpage at http://www.fao.org/documents/
2009-11-22 RE back to www.agrochall.gl