a stable longterm domestic policy framework with wide political support helps provide investment certainty although global uncertainties will still cause investors to question the probability of these policies being modified in the future to provide this sort of certainty the eu has already set targets for in its emissions trading system and intends to set targets in the next few years emissions trading schemes ets are currently regarded as the most politically feasible means of pricing greenhouse gas emissions aiming at providing appropriate incentives for investment in lowcarbon technologies and demand reduction however the detailed design of these schemes matters particularly setting the overall cap on emissions at a level that requires emissions reductions from participants