Biogenic Carbon Energies Limitations

Chapters 2 to 4 have presented reasoned hypotheses for the evolution by source of global carbon energy supplies in the 21st century. This has shown that renewables will do no more than modestly supplement the increasingly important contributions of coal, oil and natural gas as they maintain the 2% per annum rate of growth in energy demand until mid-century. Thereafter, there will be a slowly declining rate of increase in the demand for energy. This will be down to only 1.2% per annum in the 2090s. As a consequence of this falling rate of increase in energy demand, the supply of renewables will still need to increase only modestly for much of the rest of the century. Indeed, any significant increases in the requirements for renewable energy supplies will, even in the later decades of the century, only occur if they are competitive with carbon fuels.

The 21st century required supply of coal will, as shown in Chapter 2, involve a cumulative total output of some 460Gtoe. This is much the same as the present declaration of proven reserves of 465Gtoe which, in turn, encompass only 8% of estimated ultimately recoverable coal resources. As it is near certain that additional reserves of coal, more than adequate to sustain the continuation of the relatively modest expansion of production from 2.2Gtoe in 2000 to 6.4Gtoe in 2100, will be declared proven in the 21st century, then a sufficiency of supplies to meet the demand is self-evident; especially in...