Building Retrofit Marginal Abatement Cost Curve (2D): A Tool for Climate Action

What is a Marginal Abatement Cost Curve (MACC)?

A Marginal Abatement Cost Curve (MACC) is a graphical representation that ranks potential actions based on their cost-effectiveness. Each point on the curve represents an action, with its position indicating the level of emissions reduction and the associated cost. The MACC helps policymakers identify the most cost-effective strategies for reducing greenhouse gas emissions.

In the context of building retrofits, the MACC shows which buildings or retrofit measures offer the greatest emission reductions at the lowest costs, allowing cities to prioritize their spending efficiently.

How Does the 2D MACC Work?

The 2D MACC in this simulation is a simplified representation that uses bars sorted by cost-effectiveness. Each bar represents a building or retrofit measure, with its position on the x-axis indicating the cost per ton of CO2 avoided and its height representing the potential emissions reduction. The y-axis shows the cumulative budget available for retrofits.

The curve forms a staircase pattern as each action is taken in sequence until the budget is exhausted, illustrating how resources are allocated to achieve maximum emission reductions within financial constraints.

Why Does Prioritization Matter?

Prioritizing actions based on cost-effectiveness ensures that limited budgets are used most efficiently. By focusing on the lowest-cost options first, cities can achieve significant emissions reductions with their available funds. This approach is crucial for maximizing the impact of public and private investments in sustainability.

The simulation allows users to explore different prioritization strategies: cost-effectiveness (the default), oldest-first (prioritizing older buildings regardless of cost), and random (selecting actions without regard to cost). Each strategy has its own implications for overall emissions reductions.

What is Wright's Law?

Wright’s law, also known as the learning curve, describes how costs decrease as a technology or process becomes more familiar and efficient. In the context of building retrofits, this means that as cities implement more retrofits, they can do so at lower costs due to improved techniques and bulk procurement discounts.

The Wright's-law scatter plot in the simulation shows how costs evolve over time, with points representing past projects or measures. This helps illustrate the potential for cost savings through experience and scale.

Frequently asked questions

Try it live

Everything above runs in your browser — open Building Retrofit Marginal Abatement Cost Curve (2D) and change the parameters while it is running. Nothing is installed, nothing is uploaded, the whole model lives in one tab.