CO2 credit or energy credit in emission trading?

Emission trading is a good concept and approach to tackle global warming. However, what “currency” or “credit” should be used in the trading has remained a debatable topic. This paper proposed an “Energy Credit” concept as an alternative to the “CO₂ credit” that is currently in place. From the thermodynamic point of view, the global warming problem is an “energy balance” problem. The energy credit concept is thought to be more thermodynamically correct and tackles the core of the global warming problem more directly. The Energy credit concept proposed can be defined as: the credit to offset the extra energy trapped/absorbed in the earth (and its atmosphere) due to the extra anthropogenic emission (or other activities) by a country or company. A couple of examples are given in the paper to demonstrate the concept of the Energy credit and its advantages over the CO₂ credit concept.