Sustainable development solar-fueled society

If we adopt the model for sustainability as we have developed in the previous two sections, then one obvious necessity is to transform a mainly fossil-fueled society into a society fueled by a more sustainable fuel such as solar energy. Solar energy is abundant and "renewable" on a time scale of millions of years. Its availability, esbmated at 2.8 x 106 Exajoules/annum (EJ/a = 1018 J/a) exceeds by far the needs of our society, 800 EJ/a even in 2040 (Table 13.2). In recent publications of Shell Intemahonal [25], the world s energy needs are estimated to be a factor 2.5-3 bmes larger in the year 2050 than in the year 2000. Not all of the 2.8 x 106 EJ/a is accessible estimates are that "only" 300-3000 EJ/a or 0.01%-0.1% can be captured. 

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