On its climate change information website, the New Zealand government explains how:
An emissions trading scheme (ETS) introduces a price on greenhouse gases to provide an incentive for people to reduce emissions and enhance forest sinks. Emissions trading provides flexibility in how participants comply with their obligations, enabling a least-cost response.
There are, of course, other ways to reduce emissions, such as traditional regulatory mechanisms. Pejorative phrases such as ‘command-and-control’ are usually used in the brief moment before regulation is dismissed from consideration. Indeed, the NZ Ministry for the Environment (MfE) asserts that imposing a price on greenhouse gas emissions is advantageous because:
It harnesses the market dynamic by providing automatic incentives for firms to invest in reducing emissions and to shift to lower-emissions products and services.
It provides flexibility for firms and fosters innovation and the seeking out of least-cost emission reduction strategies.
But something rather important is being glossed over here: An ETS doesn’t provide an automatic incentive for all firms to reduce emissions.
And, it turns out, this simple observation leads to some very awkward conclusions that have not been part of the carbon trading debate.