Deeper Thinking: Changing our mindset with building energy audits to look for deeper carbon reduction strategies

This paper defines deep carbon retrofits for commercial buildings, describes practical challenges and strategies for implementing deep carbon retrofits, and shares successful case studies with reductions in the 50-90% range.

Published by the American Council for an Energy-Efficient Economy (ACEEE) as part of the 2020 Summer Study on Energy Efficiency in Buildings. 


For over 30 years, commercial energy audits have been the cornerstone of energy reduction programs for existing buildings.  In the last several years, the global importance of climate change has shifted the focus from strictly energy use and cost reduction to carbon reduction.  This has resulted in a new approach of exploring and implementing deep carbon retrofits.

This paper will focus on several key areas:

  • A comparison of energy audits and deep carbon retrofit studies in the commercial sector
  • Sample scope of work for a deep carbon retrofit study
  • Objectives and benefits of a deep carbon retrofit to shift the mindset of practitioners and building owners
  • The practical challenges of implementing deep carbon retrofits
  • The benefits of a low carbon grid in pursuing electrification
  • Key factors to achieve results in deep carbon retrofits

Successful case studies of deep carbon retrofits shared in this paper include those from a community center, private office buildings, a laboratory, as well as an advanced education institute. We will discuss how these organizations were able to achieve carbon reductions in the 50-90% range.