This would then change the calculation. Wikipedia (http://en.wikipedia.org/wiki/Fossil-fuel_power_station http://en.wikipedia.org/wiki/Fossil-fuel_power_station

This would then change the calculation. Wikipedia (http://en.wikipedia.org/wiki/Fossil-fuel_power_station http://en.wikipedia.org/wiki/Fossil-fuel_power_station) says that the efficiency for a coal powered generator is only 33%, as opposed to 56-60% of a combined cycle gas powered generator. Based on the above data, if one assumes only hydro carbons are used, for power production, that would give 37% natural gas and 63% coal. Then, the average efficiency is 33.63+60.37= 43%. So, the over all efficiency would be 1.14*43/60=.817 km/MJ, which now doesn't look that impressive. Also, I am not sure if the calculation accounts for transportation loss involved in getting the coal and oil to the power plant.