The Resources of the Earth - Thanatia: The Destiny of the Earth's Mineral Resources - page 155

Table 6.7. World fossil fuel resources

Fuel Proven reserves Estimated additional reserves

(Gtoe) 3 (Gt) (Gtoe) 3

(Gt)

Conventional fuels
Coal 1 Bituminous (+
anthracite)

404.76 253.72 800.77 501.96

Sub-
bituminous

260.79 117.70 392.24 177.03

Lignite 195.39 55.52 771.70 219.30

188.78 2 141 5 Oil 190.69 142.43

187.14 Tm 3 168.93 2 500 Gtoe 4 Natural gas

Non-conventional fuels
Coal bed methane 231.68 4
Gas from fractured oil shale 412.22 4
Gas from tight sands 176.66 4
Clathrates 20 10 15 m 3 18,053.28 5
Oil shale 408.60 6 91.72 1446.15 5
Natural bitumen 338.2 6 324.66 110.07 6 105.66
Extra-heavy oil 314.31 6 303.23 25.96 6 25.04
Peat 108.53 7 25.29 535.46 7 124.80
1 Distribution according to “Survey of energy resources 2010” (WEC, 2010). The total amount
of coal is 860.9 Gt (WEC, 2010).
2 Reported value by BP (2011).
3 Energy values for all the fuels were calculated using the net calorific values reported by the
IPCC (Eggleston et al., 2006).
4 Energy data taken from Gregory and Rogner (1998).
5 Data taken from Kvenvolden (1999); Beauchamp (2004).
6 Data taken from WEC (2007).
7 Data taken from Alpern and Lemos de Sousa (2002).

6.7 Energy resources summary

Table 6.8 summarises the results discussed in the previous sections. It shows all
of the available resources that Nature provides, those which could be potentially
obtained using technology into the near future and those which are used today. All
consumption figures in Table 6.8 are taken from the end of 2010, except for those
of biomass and non-conventional fossil fuels, which are 2005 values.
It must be pointed out that the data in Table 6.8 is an approximation and must
be treated as such. In any case, it might increase, as technology permits a more
e cient use of resources and an ability to exploit those fuels which are not currently
recoverable. It should also be remembered that the future of a resource is not
typically the product of a unilateral decision. This is because whilst governments
and global accords play a key role in defining objectives and implementing policies, it