What Are Marginal Abatement Cost (MAC) Curves and How Do They Support Smarter Decarbonization Pathways

Hunter Brett, P.Geo., M.Sc.

Associate, Decarbonization

Richard Hares P.Eng.

Vice President, Americas, Decarbonization & Facilities

What Are Marginal Abatement Cost (MAC) Curves?

Marginal Abatement Cost (MAC) curves are powerful analytical tools that help companies identify, quantify, and prioritize emissions reduction measures based on their cost-effectiveness. A MAC curve visually ranks emission abatement options by cost per unit of carbon dioxide equivalent (CO2e) avoided against the potential volume of emissions reduced. By ordering measures from lowest to highest marginal cost, companies gain clarity on which decarbonization strategies deliver the most emission reductions for the least expense.

In the context of energy-intensive industries such as oil & gas, utilities and investors in North America, MAC curves serve as a critical roadmap for planning and investment decisions. They enable companies to balance environmental goals with economic viability. Understanding MAC curves is essential for sustainability managers, energy executives, and investors seeking data-driven pathways to decarbonize operations while maintaining profitability.

How Do MAC Curves Support Decarbonization Decision-Making?

MAC curves guide decision makers by providing an intuitive visual framework where emission reduction opportunities are arranged along a cost and impact spectrum.

Prioritizing Cost-Effective Emissions Reduction Opportunities

This facilitates several key aspects of strategic planning:

• Prioritization: Companies can focus first on “negative cost” or low cost measures and identify quick wins.
• Investment optimization: By comparing costs and benefits across options, capital can be allocated toward actions offering the greatest emissions reduction per dollar spent.
• Scenario analysis: MAC curves allow flexible modeling to integrate evolving technology costs, regulations, and carbon pricing, helping firms adapt plans proactively.

How Are MAC Curves Applied in Real-World Decarbonization Projects?

In North America, MAC curves have become particularly vital in navigating complex regulatory and market conditions. Evolving climate policies, carbon pricing, emissions caps, and clean energy incentives, which create both opportunities and constraints are shaping decarbonization strategies.

Sproule ERCE has applied MAC curve analyses in projects globally. An example is provided here:

These efforts underscore how MAC curves help identify cost effective decarbonization options aligned with regional policy drivers like the USA’s tax credits and Canada’s Clean Fuel Standard.

What Challenges and Opportunities Come with Using MAC Curves?

Common Challenges When Developing MAC Curves

While MAC curves are valuable decision-support tools, their effective use faces several challenges:

• Data quality and availability: Accurate emissions inventories and cost estimates require consistent and high quality data, which can be lacking due to dispersed infrastructure and limited real time monitoring.
• Regulatory uncertainty: Shifting policies at federal and provincial/state levels introduce risks affecting abatement costs and project viability.
• Operational complexity: Emission reductions often spans diverse assets and processes over multiple years, complicating the aggregation and comparison of measures.
• Dynamic markets: Changing energy prices and technology developments necessitate frequent updates to MAC curves.

Turning Decarbonization Challenges into Strategic Opportunities

However, these challenges also present opportunities. Companies that invest in robust data collection, maintain flexible decarbonization pathways, and integrate regulatory trends can leverage MAC curves to identify innovative solutions while managing risks and costs.

How Does Sproule ERCE Develop Marginal Abatement Cost (MAC) Curves?

Our Approach to MAC Curve Development

Sproule ERCE combines deep technical expertise, economic understanding, and regulatory insight to develop MAC curve analyses that are both rigorous and practical. Our methodology includes:

• Comprehensive modeling incorporating OPEX and CAPEX impacts.
• Ranking and screening abatement options to highlight both immediate wins and longer-term investments.
• Aligning emissions reduction strategies with growth and regulatory trends for sustainable outcomes.
• Detailed site visits and emissions verification for data.

Example of a North American MAC Curve Project

For example, in a recent project in North America, Sproule ERCE:

• Conducted facility emission benchmarking using process flow diagrams (PFDs), piping & instrumentation diagrams (P&IDs), heat and mass balances.
• Developed a prioritized list of decarbonization options, financially modeled to assess economic viability.
• Delivered actionable plans tied to client specific assets, supporting practical implementation paths.

This hands on approach ensures clients can pursue cost effective emissions reductions aligned with evolving climate policy and market dynamics.

Why Are MAC Curves Essential for Building Smarter Decarbonization Pathways?

Marginal Abatement Cost curves are indispensable for companies seeking to navigate the complex landscape of decarbonization in North America. By quantifying and ranking emission reduction measures by cost and impact, MAC curves provide a clear framework to invest wisely, innovate, and meet climate targets without sacrificing profitability.

Sproule ERCE’s integrated expertise helps clients leverage these tools effectively, combining data driven analytics with on the ground knowledge to build smarter, adaptable decarbonization pathways. To learn how Sproule ERCE can support your decarbonization journey through customized MAC Curve analysis and strategic advisory, please contact us.

Learn how Sproule ERCE helps companies decarbonize with practical strategies:

Midstream and Facilities Decarbonization Roadmap – Sproule ERCE