From a technical point of view, they are not the same. I don't see how we can compare the price of emission intensity and the price of emissions per se.
For example, in one study I carried out in the past, when we cannot use a market-based instrument, how can the government design an emissions intensity to achieve this given level? On a theoretical basis, this is possible, but as far as asking firms to trade emissions intensity permits, from my perspective, it's impossible. It will be very difficult to assess who is doing what and what we are trading.