It's a great question.
In terms of the lowest cost, it's obviously what you can do to avoid emissions. In other words, what can you do to make sure you're operating as efficiently as possible? That's one of the things that we in business constantly do. We look at where we are being inefficient, because that adds cost.
From a higher-cost perspective, I think it comes right down to what the cost is of an abatement opportunity, based on the carbon price and, as I think Tristan was saying, based on the uncertainty associated with that carbon price or any of the other existing regulations, because you're taking a risk. For a major project, for a project in which you're hoping to capture a lot of emissions, if you don't have confidence that the carbon price will be where it's at or that a clean fuels regulation will be able to generate the credits, you're taking on risk. You're taking on investor risk.
Investor risk is just like it is for you and me. We give money to a company and we hope on a return. We buy a house and we hope the investment in that house doesn't go down but stays equal or goes up. We have to be thoughtful about the investment decisions we make. Where there's uncertainty, there's risk.
Therefore, the way we can address some of these big opportunities to capture emissions, as an example, is by working with government, with existing regulations, and finding ways to reduce that risk by looking at things that could make that investment economic where it's not.