114. EROEI AS A POLITICAL NUMBER
When talk turns to the EROEI of mining coal, the EROEI advocates want to show that coal mining is becoming increasingly unfeasible, so they try to make EI (Energy Invested) as large as they can. For example, in the case of strip mining, they stress that mining companies are supposed to put the overburden back into the hole, compact the dirt, do landscaping etc., and that the energy necessary to do that restoration must be included in EI.
Whatever your position on such restoration, it is clearly a political/regulatory requirement, not a physical requirement necessary to harvest and use the coal energy.
If we include energy inputs like this, then EROEI is not an objective, physical number. It's an advocacy number.
It may be that the EROEI of coal (or other energy sources) is decreasing not because the energy is getting harder to mine or use, but because of an ever increasing load of regulatory requirements. In that case, EROEI isn't a hard physical number at all. It's a value which depends on the regulatory climate. Which of course means that the EROEI of coal can also be instantaneously increased by eliminating regulations (i.e. eliminating the requirement to fill in overburden). EROEI loses a lot of credence as a hard physical limit, if the coal lobby can change it by making a few phone calls to the right people.