ULTRALIGHT-HYBRID VEHICLE DESIGN: OVERCOMING THE BARRIERS TO USING ADVANCED COMPOSITES IN THE AUTOMOTIVE INDUSTRY

This research paper by Rocky Mountain Institute (RMI) argues that the automotive industry's failure to adopt advanced composite materials in the body-in-white (BIW) is due to a reliance on incremental, component-based substitution. The authors propose a "leapfrog" strategy: a whole-system redesign using an all-advanced-composite monocoque BIW integrated with a hybrid-electric "hypercar" concept. This approach aims to overcome cost, manufacturing, and cultural barriers by maximizing mass reduction and simplifying assembly.

• The "hypercar" concept integrates an ultralight, aerodynamically slippery monocoque body with a hybrid-electric drive to achieve significant efficiency gains. This combination can reduce curb mass by approximately 2–3-fold, air drag by 2–3-fold, rolling resistance by 3–5-fold, and fuel consumption by 5–10-fold.
• Advanced composite bodies-in-white (BIW) offer substantial weight savings compared to traditional materials, with the potential to be up to 67% lighter than a conventional steel unibody for equivalent size and safety.
• The authors argue that a "leapfrog" approach—replacing the entire BIW with advanced composites rather than substituting parts incrementally—is the most effective way to overcome industry barriers. This strategy allows for radical reductions in parts count and assembly effort, potentially reducing the cost of BIW assembly to approximately 10% of that required for steel.
• Cost is a primary barrier, but the paper suggests that an all-advanced-composite monocoque BIW could reach manufacturing cost parity with a steel unibody at production volumes of 100,000 vehicles per year. This breakeven point is influenced by carbon-fiber prices and the degree of mass optimization; for example, a design 67% lighter than steel could be viable with carbon fiber prices only slightly below current market rates.
• Several technical barriers to high-volume production are identified as manageable through optimization rather than new invention. These include the high cost of carbon fiber (with some commodity-grade fibers as low as $17.60/kg), the difficulty of creating complex preforms, and slow liquid composite molding (LCM) cycle times, which could be mitigated by E-beam curing or thermoplastic resins.
• Industry surveys reveal that the barriers to adoption are as much cultural as technical. Automakers cite inexperience, unfamiliarity, and discomfort with composites as top disadvantages, while suppliers point to the "sunk cost" mentality associated with massive existing steel-based infrastructure.

APA

Brylawski, M. M., & Lovins, A. B. (n.d.). ULTRALIGHT-HYBRID VEHICLE DESIGN: OVERCOMING THE BARRIERS TO USING ADVANCED COMPOSITES IN THE AUTOMOTIVE INDUSTRY. RMI. https://rmi.org/app/uploads/2017/05/RMI_Document_Repository_Public-Reprts_T95-39_UHVDAdvCompAuto.pdf

Chicago

Brylawski, Michael M., and Amory B. Lovins. ULTRALIGHT-HYBRID VEHICLE DESIGN: OVERCOMING THE BARRIERS TO USING ADVANCED COMPOSITES IN THE AUTOMOTIVE INDUSTRY. RMI, n.d. https://rmi.org/app/uploads/2017/05/RMI_Document_Repository_Public-Reprts_T95-39_UHVDAdvCompAuto.pdf.

Wikipedia

{{cite report |last1=Brylawski |first1=Michael M. |last2=Lovins |first2=Amory B. |title=ULTRALIGHT-HYBRID VEHICLE DESIGN: OVERCOMING THE BARRIERS TO USING ADVANCED COMPOSITES IN THE AUTOMOTIVE INDUSTRY |publisher=RMI |url=https://rmi.org/app/uploads/2017/05/RMI_Document_Repository_Public-Reprts_T95-39_UHVDAdvCompAuto.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{brylawskindultralighthybrid, author = {Brylawski, Michael M. and Lovins, Amory B.}, title = {{ULTRALIGHT-HYBRID VEHICLE DESIGN: OVERCOMING THE BARRIERS TO USING ADVANCED COMPOSITES IN THE AUTOMOTIVE INDUSTRY}}, institution = {RMI}, url = {https://rmi.org/app/uploads/2017/05/RMI_Document_Repository_Public-Reprts_T95-39_UHVDAdvCompAuto.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }