At Wren, we remove CO₂ from the atmosphere by collaborating with Projects. A portfolio is a collection of projects with specific weights, adding up to 1.

Each project has a different cost_per_ton (the price of a carbon credit representing one metric ton of CO₂ equivalents), owing to the different costs involved in each method of carbon sequestration. When multiple projects are combined into a portfolio, we combine their respective prices and weight into a rolled-up cost_per_ton for the entire portfolio.

When you place an Offset Order on Wren, you can choose which projects you'd like to support by choosing a portfolio. Right now, we do not support the ability for users to create custom portfolios on the fly when they place orders. However, we provide some options for you in the form of pre-built portfolios:

1. You can choose to offset carbon with a single project. To enable this, we have created and supplied portfolios for each project to simply dedicate 100% of the funds to that project.
2. Alternatively (and by default), you can support the Wren Climate Fund, a portfolio of all projects on Wren weighted every month by what we think needs more or less funding.

For example, the "Wren Climate Fund" portfolio contains 5 different projects, while the "Clean Cooking Fuel for Refugees" is a portfolio of a single project — the “Clean Cooking Fuel for Refugees” project. We know this system may seem a little convoluted, but just know that anything you purchase on Wren will support a Portfolio.

You can learn in-depth information about all of our projects and their verification standards by visiting our website: https://www.wren.co

Attributes

id number

Unique identifier for the object

name string

The name of the portfolio.

cost_per_ton decimal number

The price, in US Dollars, to offset one metric tonne of carbon dioxide (or carbon dioxide equivalents) from the atmosphere using this portfolio.

projects array of Projects