Sustainability 2011 , 3
1901
Table 3. Various conversions used commonly in EROI analysis.
Unit Conversion Factor Reference
Primary Energy (Heat Content)
Oil 6.12 (GJ/bbl) [31]
Natural Gas 41 (KJ/m^3 ) [31]
Coal 22 (GJ/tonne)a [31]
Energy Intensities (for year 2005) MJ/$
average U.S. economy 8.3 [15]
average heavy industry 14 [15]
average oil & gas exploration and dev. 20 [12]
Material Costs GJ/tonne
Aluminum 241.2 [32]
100.2 [33]
272.2 [34]
11.7b–140 [35]
Steel 32.4 [32]
9.43c–25.2d [35]
Copper 200.2 [33]
93.7 [36]
104.4 [37]
51.7–179.7 [38]
0.08–255.7 [39]
Cement 5.5 [34]
Iron Ore 0.34–2.9 [39]
Stone 0.021–0.057 [39]
Limestone 0.034 [39]
Lead 1.4–31.1 [39]
Zinc 76 [39]
Phosphate 0.083–0.349 [39]
Glass
Molten Flint Glass 14.2 [35]
Molten Emerald Glass 11.7 [35]
Molten Amber Glass 13.2 [35]
Plastics
Polyvinyl Chloride (PVC) 59.8 [35]
General Purpose Polystrene (GPPS) 84.8 [35]
High Density Polyethylene (HDPE) 89.5 [35]
High Impact Polystyrene (HIPS) 87.4 [35]
Low Density Polyethylene (LDPE) 93.9 [35]
Polyethyene Terephthalate (PET) 88.9 [35]
Polypropylene (PP) 88.5 [35]
Linear Low Density Polyethylene (LLDPE) 83.4 [35]
Woode
Dry Lumber 2.33 [35]
Green Lumber 0.95 [35]
a Average U.S. coal production; b secondary aluminum ingot; c Electronic Arc Furnace
Billet; d Hot Rolled Coil (Integrated Mill); e Average of hardwood and softwood.