Carbon Footprint Reduction Award sponsored by Shell Low Carbon Solution Business PDF Free Download
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Team ID: MX0002001 EcoVolt CCM
Carbon Footprint Reduction Award sponsored by Shell Low
Carbon Solution Business
EcoVolt CCM
Team ID: MX0002001
1 Introduction
Sustainability stands as the defining challenge for the automotive industry, driving a critical
shift toward minimizing environmental impacts without compromising performance, safety, or
structural integrity. Within this context, the EcoVolt Racing Team has adopted a
high-performance carbon fiber monocoque for its Shell Eco-marathon prototype—a decision
aimed at enhancing vehicle efficiency through reduced weight and improved aerodynamics.
However, the adoption of carbon fiber poses a significant challenge to the team’s environmental
objectives, as its production is highly energy-intensive, reliant on fossil fuel-derived precursors
such as polyacrylonitrile (PAN), and characterized by limited recyclability. Preliminary
evaluations conducted by the team identified the carbon fiber monocoque as the single largest
contributor to the vehicle’s total carbon footprint, particularly due to its elevated fossil-based
global warming potential (GWP).
To address this trade-off between structural performance and environmental
responsibility, the EcoVolt Racing Team initiated a multi-faceted sustainability initiative
centered on material innovation and Life Cycle Assessment (LCA). The key objective of this study
is to explore the feasibility of replacing the carbon fiber monocoque with a more sustainable
alternative—specifically, a cotton fiber composite reinforced with epoxy resin—while ensuring
full compliance with competition regulations concerning safety, durability, and functionality. This
investigation includes a comprehensive cradle-to-gate analysis of the environmental impacts
associated with raw material extraction, water and energy consumption (notably leveraging
photovoltaic energy from planned on-site solar panel installations), and emissions to air, water,
and soil.
Complementing this primary initiative, two additional material substitution projects
were developed to address other high-impact components. The first involves the use of mushroom
mycelium-based bioplastics to replace petroleum-derived plastics in non-structural parts such as
pedals and mirror bodies. The second focuses on recycling PET bottles into 3D printing filament
for prototyping and small-scale part fabrication, thereby promoting a circular economy approach
and reducing reliance on virgin plastics. These efforts, collectively, not only aim to reduce the
environmental burden of vehicle production but also to evaluate the full life cycle performance of
alternative materials. A detailed LCA was conducted for the cotton fiber monocoque to quantify
its environmental benefits relative to traditional carbon fiber composites, offering valuable
insights into its potential for broader implementation in sustainable vehicle design.
2 Goal and Scope
The present Life Cycle Assessment (LCA) aims to quantify the environmental impacts associated
with the production of a monocoque structure fabricated from carbon fiber composite materials,
commonly utilized in lightweight automotive and aerospace applications. The analysis focuses on
identifying critical hotspots within the supply chain and manufacturing processes that
significantly contribute to global warming potential (GWP) and related environmental burdens.
The assessment is based on a functional unit of 1 kg of carbon fiber monocoque, covering a
cradle-to-gate system boundary that includes raw material extraction (carbon fiber, epoxy resin,
and additives), energy consumption during production, and emissions to air, water, and soil. To
accurately define the system’s output flows, extensive research was conducted to identify the
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Team ID: MX0002001 EcoVolt CCM
specific chemical compounds emitted throughout the process, and corresponding emission factors
were incorporated into the model.
Additionally, average energy consumption calculations for each production machine were
performed, based on empirical data and equipment specifications, to ensure precise modeling of
electricity demand and its environmental impact. The model was developed using SimaPro 9.5.0
software, leveraging the Ecoinvent 3 database (allocation, cut-off by classification), and applying
the IPCC 2021 GWP100 V1.02 method to assess climate change impacts associated with fossil,
biogenic, and land transformation emissions. This LCA was conducted with the specific purpose
of enabling a detailed environmental comparison against an alternative monocoque design made
from cotton fiber composite, thereby assessing the potential of this natural fiber to serve as a
lower-impact substitute for traditional carbon-based materials.
3 Life Cycle Impact Assessment
3.1 Carbon fiber
Figure 1. Life Cycle Assessment (LCA) of the monocoque structure
The total amount of The total GWP for producing 1 kg of carbon fiber monocoque was
calculated at 51.1 kg CO₂-equivalent. The major contributors to this impact, as identified through
the process contribution analysis, are:
Input/process
Quantity
GWP [kg CO₂-eq]
Contribution [%]
Carbon fiber reinforced plastic,
injection molded
0.389 kg
32.4
63.4
Epoxy resin, liquid {GLO}
2.22 kg
15.5
30.3
Electricity, medium voltage {MX}
1.0 MJ
0.71
1.4
Glass fiber {RoW}
0.3 kg
0.781
1.5
Electricity, high voltage {MX}
0.799 MJ
0.264
0.5
Electricity, low voltage {MX}
2.0 MJ
0.406
0.8
Polymer foaming {GLO}
0.333 kg
0.284
0.5
Polyurethane, flexible foam {GLO}
0.03 kg
0.164
0.3
Table 1: Contributors of global warming potential of the production of the monocoque structure
The Life Cycle Impact Assessment reveals that the predominant contributor to the total
Global Warming Potential (GWP) of the carbon fiber monocoque is the carbon fiber reinforced
plastic, injection molded, responsible for 63.4% of the total emissions. This substantial impact
stems from the inherently energy-intensive manufacturing process and reliance on fossil-based
precursors such as polyacrylonitrile (PAN) and epoxy resin matrices, both of which require
significant thermal and chemical processing. The epoxy resin, liquid {GLO}, used as a binding
matrix, represents the second-largest emission source with 15.5 kg CO₂-eq, corresponding to
30.3% of total GWP, primarily due to its petrochemical origin and the high thermal energy
requirements during polymerization and curing stages.
Furthermore, electricity consumption during composite fabrication, especially in curing
ovens and molding operations, contributes an additional 2.7%, with medium voltage electricity
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Team ID: MX0002001 EcoVolt CCM
{MX} accounting for 1.4%, and low and high voltage electricity together comprising 1.3%
of emissions. Secondary inputs such as glass fiber reinforcement (1.5%) and polymer foaming
agents (0.5%) exhibit comparatively minor contributions, primarily associated with
tooling and material stabilization functions. This distribution underscores the criticality of raw
material selection and energy sourcing in mitigating environmental impacts in advanced
composite production.
3.2 Cotton fiber
Figure 2. Life Cycle Assessment (LCA) of cotton fiber
Input/process
Quantity
GWP [kg CO₂-eq]
Contribution [%]
Cotton fiber {RoW}
1.5 kg
1.14
64.0
Fiber, flax {GLO}
1.0 kg
0.57
32.0
Epoxy resin, liquid {RoW}
2.0 kg
0.15
8.4
Soda ash, dense {GLO}
0.05 kg
0.03
1.7
Triethylene glycol {GLO}
0.02 kg
0.01
0.5
Ethoxylated alcohol (AE3) {RoW}
0.02 kg
0.01
0.5
Lubricating oil {RoW}
0.01 kg
0.005
0.3
Transport, freight, lorry,
unspecified {GLO}
2.0 tkm
0.02
1.1
Electricity, low voltage {MX}
(photovoltaic, 3kWp system)
1.5 kWh
0.12
6.7
Table 2: Contributors of global warming potential of the production of cotton fiber.
The Life Cycle Assessment (LCA) of the cotton fiber monocoque reveals a total Global
Warming Potential (GWP) of 1.78 kg CO₂-equivalent per kilogram of product, representing a
substantial reduction in carbon footprint compared to conventional carbon fiber composites. The
dominant contributor to this impact is the cotton fiber supply chain, accounting for 64% of total
GWP due to emissions associated with cotton cultivation, harvesting, and processing, particularly
in regions utilizing conventional agricultural practices with significant water and fertilizer
inputs. Flax fiber, employed as a reinforcing agent, contributes an additional 32%, attributed to
its lower energy requirements during cultivation and minimal processing.
Epoxy resin consumption, although necessary for composite integrity, accounts for only
8.4% of GWP due to reduced material usage and optimized curing cycles. Ancillary materials
such as soda ash, triethylene glycol, and ethoxylated alcohols contribute marginally (<2.5%),
while transport and photovoltaic-sourced electricity collectively add 7.8%, underscoring the
system's reliance on renewable energy. These findings demonstrate that, through strategic
material substitution and low-impact energy sourcing, cotton-based monocoques offer a
high-performance, low-emission alternative, aligning with sustainable manufacturing objectives
and circular economy principles.
Another proposed idea was the inclusion of a made-from-scratch hibiscus fiber textile.
However, this was decided against due to two main factors. Firstly, hibiscus fibers show
difficulties when absorbing epoxy resin in experiments due to their hydrophilic nature and the
lignin and hemicellulose bonds that form it. Furthermore, due to the lack of available suppliers
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Team ID: MX0002001 EcoVolt CCM
specialized in non-commercial fibers, most of the theoretical findings cannot be
empirically tested as all specimens needed for testing have to be made from scratch.
4 Environmental Performance Interpretation
The comparative Life Cycle Assessment (LCA) of monocoque structures fabricated from carbon
fiber composites and natural cotton fibers demonstrates a profound divergence in environmental
performance across all Global Warming Potential (GWP) categories—fossil, biogenic, and land
transformation—based on the IPCC 2021 GWP100 V1.02 method.
Figure 3. Comparison of GWP100 (fossil, biogenic, land transformation) between cotton fiber and
carbon fiber monocoque. [Functional Unit: 1 kg of product]
The carbon fiber monocoque exhibits a total GWP of 51.1 kg CO₂-equivalent per kilogram,
with fossil-based emissions contributing 50.9 kg CO₂-eq, primarily due to the energy-intensive
synthesis of polyacrylonitrile (PAN)-based carbon fibers and petrochemical-derived epoxy resin,
both of which undergo high-temperature polymerization and curing processes heavily reliant on
fossil fuels. Biogenic GWP is minimal at 0.0889 kg CO₂-eq, while land transformation impacts
reach 0.0416 kg CO₂-eq, stemming from the extraction and processing of non-renewable inputs.
In contrast, the cotton fiber monocoque yields a dramatically reduced GWP of 1.78 kg CO₂-eq per
kilogram, with fossil emissions at 1.78 kg CO₂-eq, biogenic at only 0.0136 kg CO₂-eq—reflecting
the cellulose-based, carbon-sequestering nature of cotton and flax fibers—and land
transformation at 0.0251 kg CO₂-eq due to more sustainable cultivation practices. This system is
further enhanced by the exclusive use of low-voltage photovoltaic electricity, as solar panels are
scheduled for installation at the production facility, enabling renewable energy inputs that
further minimize indirect emissions.
Although the cotton monocoque may physically weigh less than its carbon counterpart,
for functional equivalence in structural performance, both systems were standardized at 10 kg
per ISO 14040/44, ensuring a valid basis for environmental comparison. When scaled to this
real-world application, total GWP rises to 511 kg CO₂-eq for the carbon fiber monocoque versus
just 17.8 kg CO₂-eq for the cotton variant, representing a net reduction of 493.2 kg
CO₂-equivalent per unit produced—a 96.5% decrease in carbon footprint, validating the natural
fiber composite as a low-emission, sustainable alternative for lightweight structural applications,
aligned with renewable resource utilization, decarbonized energy systems, and circular economy
principles.
5 Technical Interpretation
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Team ID: MX0002001 EcoVolt CCM
After researching various types of natural fibers, thread directions, and fiber-epoxy
composites, tests were conducted using a universal testing machine, obtaining the following
experimental values. Although these are lower than those reported in the literature, they closely
reflect reality due to the lack of experiments performed with composites using Ecopoxy resin and
the differences between the thickness of the flat specimens used.
Composite Material
Elongation at Break
[%]
Tensile Strength
[MPa]
Tensile Modulus
[GPa]
2-layer cotton (45° &
90°)
1.19
21.16
1.96
1-layer cotton (45°)
1.25
18.22
1.43
1-layer cotton (90°)
1.44
25.61
1.80
1-layer jute (90°)
1.84
35.29
1.92
2-layer jute (90°) &
cotton (45°)
1.24
31.49
3.65
Table 3: Mechanical properties of experimental fiber-ecopoxy composites.
This composite exhibits moderate stiffness with a tensile modulus of 1.96 GPa and a
tensile strength of 21.16 MPa. Its elongation at break is relatively low (1.19%), making it prone
to brittle failure under high stress. While it does not excel in either strength or flexibility, it offers
a balanced performance that could be suitable for applications where moderate rigidity and
strength are required. However, other specimens demonstrate superior mechanical properties.
Each composite material was analyzed based on rigidness (stiffness), fragility
(brittleness), and overall performance. The 2-layer cotton (45°) specimen, with the lowest tensile
modulus (1.43 GPa), was the least rigid; its tensile strength (18.22 MPa) is also the lowest,
making it less viable for high-stress applications. Meanwhile, the 2-layer cotton (90°) stands out
as the best-performing cotton-based material, with the highest tensile strength (25.61 MPa) in its
category. It also offers a moderate tensile modulus (1.80 GPa) and an elongation at a break of
1.44%, making it less brittle than the other cotton-based specimens. The 1-layer jute (90°)
specimen, which was based on the material used last year, offered the best mechanical balance,
being the least brittle, most ductile, and strongest composite overall.
However, the hybrid specimen (2-layer jute (90°) & cotton (45°)) had the highest tensile
modulus (3.65 GPa), making it the most rigid and stiff material tested, with a high tensile
strength. Therefore, this composite is ideal for applications where high stiffness and load-bearing
capacity are essential, such as the Shell Eco-marathon; further experimentation may help
improve its overall elongation at break. Given the mechanical viability and adaptability of cotton
fiber in composite applications—especially when paired with epoxy resins—the environmental
implications of using natural fiber-based monocoques merit critical examination. Although
cotton-epoxy composites exhibit lower mechanical performance relative to carbon fiber-epoxy
composites, their significantly lower environmental footprint positions them as a sustainable
alternative in non-structural or semi-structural lightweight applications.
Figure 2. Fiber-ecopoxy flat specimens, from left to right: 1-layer cotton (45°), 1-layer cotton (45°
& 90°), 1-layer jute (90°), 2-layer jute (90°) & cotton (45°), and 2-layer cotton (90°)
Furthermore, to implement this idea, economic viability is needed to evaluate its
feasibility, as natural fibers represent a low-cost alternative to carbon fiber textiles. The cost of
the fabric depends on the method of obtaining it. Within the Mexico City Metropolitan Area,
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Team ID: MX0002001 EcoVolt CCM
there is a commercial fabric, called Polyreciclado Tubular, sold by ecologic fabric vendor
Texterra. However, the fabric consists of 50% recycled cotton and 50% recycled polyester (priced
at $171 MXN per 10 meters) or organic cotton fabric (priced at $399 MXN per 15 meters) [Telas
Texterra, 2025].
6 Complementary Strategies for Carbon Footprint
Reduction
6.1 Bioplastics Made from Mushroom Mycelium
This proposal, initially addressed in the 2024 Carbon Footprint Reduction Award paper,
highlighted the potential of mushroom mycelium as a sustainable alternative to petroleum-based
plastics in the vehicle's design by significantly reducing emissions, energy consumption, and
long-term environmental impact. Mycelium is biodegradable, lightweight, grown from
agricultural waste, and offers acoustic and thermal insulation. It can also enhance fuel efficiency
by reducing vehicle weight while maintaining safety and performance, making it a promising
material for racing applications.
Under this premise, a material based on oyster mushroom (Pleurotus ostreatus) mycelium
was started and developed to replace the existing petroleum-based pieces in the vehicle, starting
with the vehicle's interior parts, such as the steering wheel and gear shifts. The inoculation with
this fungus was carried out using two different methods; the first involved injecting rye and
popcorn seeds with commercial syringes containing liquid culture medium, while the second used
commercially available seeds that were already colonized with mycelium. Subsequently, the seeds
are spread on a substrate based on sawdust and soybean flour, taking into account that the
oyster mushroom is a saprophytic organism. The substrate containing the fungus was then
monitored until it had completely spread, forming a solid piece that was subsequently dried to
get rid of all the moisture in the piece, increase the piece's hardness, and stop the fungi's growth.
Mycelium-based materials can also be a good alternative for insulation materials and parts
in the vehicle, such as the firewall. Incorporating 50wt% (weight percentage) glass fines inside
mycelium composites has much longer times to flashover (311-370 s) than synthetic materials,
such as extruded polystyrene insulation foam (XPS) (61 s) and particleboard (173 s), relying on
the fact that the addition of glass fines inside mycelium composites increases its silica content,
therefore improving the composite's fire resistance properties [Guerrero de Escalante, 2023].
Oyster mushroom's mycelial networks present an ability to process electrical signals when
stimulated and discriminate between frequencies in a fuzzy or threshold-based manner, thus
generating the opportunity area for the design of mycelium-based electronic components inside
the vehicle [Przyczyna et al., 2022]. The development of biodegradable sensor networks based on
leveraging the material's properties serves for real-time environmental monitoring and adaptive
response systems inside the vehicle aiming to create bioelectronic components capable of
detecting and responding to changes in temperature, humidity, and structural integrity, aligning
with the growing need for recyclable and eco-friendly automotive technologies, reducing
electronic waste while enhancing vehicle adaptability and efficiency.
Mycelium-based materials have several potential applications in cars, particularly in
interior components such as dashboards, doors, steering wheels, and levers, serving as a
sustainable alternative to polystyrene and Styrofoam. In 2011, the automotive company Ford
collaborated with Ecovative Design to develop fungus-based vehicle parts, including those
mentioned above [Alsever, 2011]. More recently, Kia has also started incorporating mycelium for
similar purposes [Villegas, 2023].
On the 2024 season’s Carbon Footprint Reduction Off-Track, the fabrication of
biocomposites made out of oyster mushroom mycelium was proposed as a future application,
that’s why throughout this season, the Ecovolt team has been working on improving the physical
and mechanical properties to assure optimal safety conditions so that in the coming seasons our
prototype contains mycelium composites either in the structure, electronics or bodywork. The
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Team ID: MX0002001 EcoVolt CCM
following figures represent the results achieved during the 2025 season, however, it’s
important to clarify that improvements in the structure must be made.
Figure 5. Circular piece made of sawdust
and oyster mushroom mycelium
Figure 6. Growing mycelium pieces in
reused plastic mold
6.2 PET Bottle Recycling into 3D Printing Filament
The team is in the final stages of developing a PET filament extruder, a device designed to
convert post-consumer PET plastic bottles into functional 3D printing filaments, promoting
circular economy practices and reducing reliance on virgin materials in additive manufacturing.
As part of this initiative, we launched an awareness campaign during the previous academic
semester, successfully engaging our university community to collect approximately 500 PET
bottles. Importantly, all bottle caps were donated to a local charity that supports cancer patients,
ensuring that the project also had a meaningful social impact.
Based on industry data, a standard 500 ml PET bottle weighs approximately 20 grams
[Plastic Odyssey, 2024], which means the collected bottles represent an estimated 10 kilograms of
raw PET material ready for extrusion. The filament produced will be used primarily for the 3D
printing of molds and components related to the development of our lightweight vehicle,
particularly in prototype fabrication and part testing, streamlining our design process through
sustainable in-house manufacturing. This initiative seeks to replace ABS (Acrylonitrile
Butadiene Styrene)—a petroleum-derived plastic with a high environmental impact, especially in
terms of fossil CO₂ emissions during production and degradation.
By substituting ABS with recycled PET filament, we aim to significantly reduce our
material-related carbon footprint and reliance on non-renewable polymers. Any surplus filament
will be donated or exchanged with individuals or institutions that require filament for social,
educational, or technological purposes, reinforcing our commitment to resource sharing and
community impact. This effort not only supports sustainable material sourcing but also lays the
foundation for localized, eco-efficient filament production, aligning with broader goals of waste
valorization, environmental stewardship, and digital fabrication innovation.
Figure 7. Prototype of the PET filament extruder.
7 Conclusions
The Life Cycle Assessment (LCA) has conclusively demonstrated that replacing the carbon fiber
monocoque with a cotton fiber composite leads to a 96.5% reduction in global warming potential
(GWP)—from 511 kg CO₂-eq to 17.8 kg CO₂-eq for a standardized 10 kg structure. This reduction
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Team ID: MX0002001 EcoVolt CCM
spans across fossil (from 50.9 to 1.78 kg CO₂-eq), biogenic (from 0.0889 to 0.0136 kg CO₂-eq), and
land transformation impacts (from 0.0416 to 0.0251 kg CO₂-eq), validating the environmental
superiority of the cotton-based solution.
The proposed material delivers favorable mechanical characteristics, including high
tensile strength (200 MPa), low density (1.48 g/cm³), and resin compatibility, enabling sufficient
structural integrity for competitive automotive applications. Additionally, the use of low-voltage
photovoltaic electricity—facilitated by the upcoming installation of solar panels at the production
site—further reduces the environmental footprint by decarbonizing energy inputs. Beyond the
monocoque, the team’s recycled PET filament initiative, sourced from 500 PET bottles, and the
integration of mycelium-based bioplastics in non-structural components, reinforce a circular
economy model and minimize dependency on fossil-derived polymers like ABS. These innovations
not only reduce waste and resource consumption but also provide tangible environmental and
functional benefits.
The findings from this LCA confirm the technical, environmental, and operational
feasibility of implementing biodegradable, renewable, and recycled materials in high-efficiency
vehicle design. The EcoVolt Racing Team is committed to scaling these solutions, improving
material circularity, and eliminating high-emission components, ensuring the transition toward a
fully sustainable and competitive mobility platform in future development cycles.
References
Alsever, J. (2011). Ecovative: Helping Ford build car parts made of mushrooms. Retrieved March
17, 2025, from https://money.cnn.com/2011/04/01/technology/ecovative/index.htm?iid=EA
Guerrero de Escalante, A. B. (2023). The development of an acoustic insulation solution using
mushroom mycelium as an alternative to synthetic foams. https://www.diva-portal.org/
smash/get/diva2:1771463/FULLTEXT01.pdf
Plastic Odyssey (2024). Mini-Guía Técnica: Impresión 3D con Botellas de PET. Retrieved March
17, 2025, from https://plasticodyssey.org/wp-content/Recycling-Academy/ES/MINI-GUIA-
Tech-PET-impresion-3D-botellas-PET.pdf
Przyczyna, D., Szacilowski, K., Chiolerio, A., & Adamatzky, A. (2022). Electrical frequency
discrimination by fungi Pleurotus ostreatus. Biosystems, 222, 104797.
https://doi.org/10.1016/j.biosystems.2022.104797
Telas Texterra. (2025). Polyreciclado Tubular | 8 colores. Retrieved March 17, 2025, from
https://telastexterra.com/tienda/textiles-reciclados/jersey-reciclado-tubular/
Villegas, I. (2023) Los Kia Concept EV3 y Concept EV4 utilizan materiales sostenibles de última
generación que transforman radicalmente el diseño interior. Retrieved March 17, 2025,
from https://press.kia.com/es/es/home/notas-de-prensa/press-releases/2023/los-kia-concept
-ev3-y-concept-ev4-utilizan-materiales-sostenible.html
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