Should we use net energy to measure global energy reserves?

Net energy is a simple concept really. Once you understand that it takes energy to get energy, the basic math is clear. To calculate the net energy available from an energy resource, you add up the energy used to find, extract, process and deliver that resource and then subtract that amount from the amount of energy the resource contains. But global reserves for finite energy resources such as coal, oil, natural gas and uranium are estimated using measures such as tons, barrels, cubic feet and pounds. These measures tell us little about the ultimate usable energy content of each type of resource.

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