Additionality
A credit is additional if the emissions reduction is beyond what would have happened in comparison with business as usual - it should be over and above. Additionality is the most contested concept in carbon markets and the primary source of integrity failures. If a solar plant would have been built anyway due to its economics, credits from it are not truly additional. Similarly, if a company was required to reduce emissions due to a regulatory requirement in the natural course of business, that reduction will not pass the additionality test. Additionality must be seen from multiple dimensions - regulatory, financial, technological.
