The Azimuth Project
Potential of solar power

Idea

This page is an investigation of the potential ability for solar power to replace fossil fuels.

Details

A priori the energy which is transported from the sun to the earth is not only enough to satisfy our nowadays energy needs but could provide a lot more. However this energy has to be captured and converted into electrical energy.

The area of the deserts is according to the Grassl, White Book by Desertec (see also the Azimuth entry Desertec) 3610 12m 236\cdot 10^{12} m^2 the average power received per square metre in deserts is according to the White Book 260W/m 2260W/m^2 \footnote{as a comparision in northern european areas solar power per area is only about 100W/m 2100W/m^2}, which gives in a year an energy of 3610 12260W8760h8210 610 12Wh=82millionTwh36\cdot10^{12}\cdot 260 W \cdot 8760 h \cdot \simeq 82 \cdot 10^6 \cdot 10^{12} Wh = 82 \;\; million\;\; Twh.

The fossil and nuclear energy consumption in 2005 was according to the white book 10710 3TWh107\cdot10^3 TWh, so the energy arriving in a year in the worlds desert is approx. 750 times more than the fossil and nuclear energy needed in 2005. Currently the conversion efficiency from solar energy to electricity from mass produced photovoltaic energy is about 15-20 %.

Let’s be pessimistic and assume an efficiency of 10 % then filling the deserts with photovoltaic elements would still give 75 times more electric energy than from the fossil and nuclear fuels in 2005.

However it is clear that filling alone 10 % of the deserts with solar energy conversion systems is a giant technological and economical task, but still -it leaves us with 7.5 times more energy than from the fossil and nuclear fuels in 2005. And even if energy demand doubles by 2050(roughly) this still leaves us with 3.75 times more energy then from the fossil and nuclear fuels a.s.o. Moreover the principle efficiency of photovoltaic solar cells can be largely improved. Currently an efficiency of 35.8 % for photovoltaic conversion (Sharp Solar Efficiency Record) can be achieved. Conversion from solar thermal energy may currently reach an efficiency of 31.25 % (Sandia solar conversion efficiency record). These rough calculations display that in principle 10/3 % = 3.33 % of the deserts area would in principle suffice (in fact by the calculations one would have 3.75 times more) for replacing the fossil and nuclear fuels of the world by solar energy until 2050.

One has to keep in mind that also here there may be limitations in terms of the materials needed for conversion, also with regard to waste. Moreover high efficiencies are currently very expensive. Technological undertakings which try to harvest solar energy from space are still in their infancy state and even more costly with regard to other energy production methods. But still - the current existing technology can be improved, also beyond the above efficiencies. However as long as other energy production means are cheaper there exists no (free) market mechanism which encourages investments in research and development.

The current text is together with the section on economic growth and Economic growth and labour part of an article draft about using games for simulating economical/political scenarios especially with respect to power generation at randform.

category: energy