Standard and Poor’s is coming out with a new rating system for the green-ness of bonds.

Our proposed Green Bond Evaluation methodology looks beyond the governance and management of a bond by providing an analysis and estimate of the environmental impact of the projects or initiatives financed by the bond’s proceeds over its lifetime relative to a local baseline. This would be in addition to assessing the governance and transparency surrounding the bond. When evaluating environmental impact, the methodology would consider both climate change mitigation and adaptation projects.

Mitigation projects focus on efforts to reduce or prevent the emission of greenhouse gases, ranging from upgrades to conventional generation projects to new renewable energy and energy efficiency initiatives. Adaptation projects aim to take practical steps toward reducing the exposure to and managing the impact of natural catastrophes, such as building the resilience of communities and critical infrastructure against an increased risk of extreme weather events due to climate change.

The output of the Green Bond Evaluation would include at least three scores (a Transparency score, a Governance score and a Mitigation score and/or Adaptation score, as relevant…

An interesting question is whether the idea is that investors would expect to make more on a green investment, or whether some investors would be willing to settle for less in exchange for the satisfaction of having a positive impact. Borrowers would have a financial incentive to be good if doing so meant a lower interest rate, which kind of supports the latter possibility. Exactly why the rating agency itself is motivated to do this was unclear to me. But after digging into the paper a little, it looks like governments and companies will have an incentive to show that they are complying with the Paris agreement, so that may be part of what is driving this.