Not stated, however:
Pg 68,
States: "comprehensive energy consumption for an output of RMB10,000 was 3.14 tonnes standard coal"
Thus, 3.14 tonnes = RMB10,000
= 3.14 tonnes = 1,446.70 USD (as at 21/5/19 - 1RMB = 0.14USD).
Thus, 3.14 Tonnes = 3140kg
= 3140kg = 1,446.70USD
Thus, 3140/1446.70 = 2.1704569kg: 1USD