Abstract: The solar energy arriving on the earth’s surface is approximately ~1.2•109 TWh/year or ~ 4.2•106 Quads/year (1 Quad=1015 BTU).
The surface area of the sun-belt deserts is approximately 36 million Km2. Each m2 of these desert areas is receiving in average 2000 KWh/year of solar irradiation, thus the whole desert area of our planet is receiving not less than 7.2•107 TWh/year or ~ 2.5•105 Quads/year (~ 6% of the overall solar energy arriving on earth).
The primary (thermal energy) consumption for 2009 is estimated to 500 Quads while the electricity demand will be less than 28000 TWh or ~100 Quads (~20% of primary consumption). It is estimated that this figure most probably could be doubled in the next 30-40 years partly because that transportation fuels could be replaced by electricity or Hydrogen made by electrolysis of clean electricity.
Let us assume that Desert Solar technology is used in desert or semi-desert areas, with an efficiency of ~1%. In order to cover 40-50% of the future electricity demand i.e. 80-100 Quads or ~22,000-28,000 TWh, we should use a desert area of 1.1-1.4 million Km2 . This is ~3-4% of desert or semi desert areas of our planet.
Desert or semi-desert areas of high solar irradiation exist in all continents and close to the big carbon emission producers.
Europe can cover its 40-50 % of its electricity demand by Desert Solar technology application in North Africa and Middle East desert and semi desert areas. An area of (300 Km X 300 Km) is sufficient.
Appropriate areas for Desert Solar technologies can be found in South West States of USA (Arizona, California, New Mexico, Nevada etc.) where the high solar irradiation is combined with mild winds. A 6% of the areas of Arizona, New Mexico and Nevada can cover USA 40-50% electricity demand.
Taklamakan desert areas in East China can be used in order to cover China’s 30-40% of China’s present and future electricity demand.
In India, Australia, South and Central America and Africa there are more than enough desert or semi- desert areas for a large scale Desert Solar technologies application.
Thus Desert Solar Technologies can be applied everywhere, where appropriate climate conditions exist.

There are three major Desert Solar technologies generating uninterrupted power electricity.
1. The Photo-Voltaic (PV) technology equipped with batteries in order to generate uninterrupted power of electricity.
2. The Concentrating Solar Power Plants (CSP) with Thermal Storage for uninterrupted power supply.
3. The Floating Solar Chimney (FSC) Technology generating uninterrupted power supply due to ground thermal storage.
A investment cost comparison is presented between these three major technologies leading to the results presented in the following table:

Although FSC technology looks superior for desert application in comparison to the other solar technologies we should notice that the FSC technology has not yet been tested in a demonstration project.

Brief Biography of the Speaker:
Prof. Christos Papageorgiou is a mechanical and electrical Engineer graduate of National Technical University of Athens (1966). He obtained his PhD by the Imperial College. He is an associate Prof. of N.T.U.A. in Electromechanical systems of Thrust and Power. His recent research interests are focused in solar thermal technologies and he is the inventor of the "Floating Solar Chimney" (www.floatingsolarchimney.gr ). In his professional career was appointed in many top managerial positions in public and private sector. The most important of which were: C.E.O. of "Olympic Airways", Chairman and President of "Hellenic Railways".