CO2 reductions by green material substitution - RD8

CO2 reductions by green material substitution

Green materials

30% reduction of CO2 emission by material substitution to green alternatives

We have gathered some of the latest information in the field of CO2 reductions by material substitution. Substitution of virgin materials to recycled or biobased alternatives.

E.g. one of the latest reports from May 2021 shows that CO2 emissions drop by 30% by changing a fossil-based value chain to a biobased plastics (See: “Greenhouse gas emissions and natural capital implications of plastics (including biobased plastics)”; May 2021; European Topic Centre on Waste and Materials in a Green Economy)

Plastic Recycling

Post Industrial Recycling

Plastic that is reused from production – e.g. plastic from the scrap bin. Plastic that have not been “out in the real world”. 

Post Consumer Recycling

Plastic that is reused after it has been at the consumer – typically collected from return systems, then cleaned and/or sorted by specialized industrial companies. The CO2 footprint from this source is typically higher than post industrial recycling as the supply chain longer and cleaning/sorting steps are included.

Bio-based Plastics

Bio-based Non-biodegradable

Bio-based plastics are plastics that are made by from renewable biological resources e.g. sugar cane, corn, or other leftovers from agriculture. Non-biodegradable means that the plastic will not automatically degrade in nature. This is good if you want to recycle the material – it is bad if you leave it the nature. The energy consumption to make the bio-based material can be higher than a fossil based production.

Bio-based & biodegradable

Based on renewable processes and can be degraded in nature. Difficult to reuse these types of plastics as they degrade with time. These types of plastics are often seen as pollution in recycling processes as their mechanical properties change over time and influence the need for a steady material quality.

 

Fossil-based & biodegradable

Fossil-based & biodegradable production represents plastics that are produced by fossil-based production methods but are biodegradable – meaning that the plastics in a given environment will be degraded by micro organisms.

See more about bio-based plastic definitions here.

Plastic Upcycling

Mechanical properties of recycled plastics are lower than commercial virgin materials due to that the recycled plastics are a mix of different materials due to sorting and cleaning processes. To compensate for this and be able to use the recycled plastics as technical plastics additives such as UV-stabilisators, flammability-stabilisators, glassfibres, etc. are added to get the desired mechanical properties – thus the amount of recycle-percentage decrease.

Aluminium: Recycling Facts

Primary vs. Recycled Aluminium

Typically there is no difference in mechanical properties or expected tolerances in primary (“virgin”) vs. recycled aluminium. 

Thus some alloys cannot be made “the recycled way” from “post consumer recycling“. “Post industrial recycling” is easier as the alloy composition is known and can be reused.

If appearance is important – note that despite that the mechanical properties are the same – anodizing can vary from product-product when using recycled alternatives.  

Alloy Types

Recycled alternatives is a mix of scrap/recycling types which in most cases are difficult to separate and extract into exact alloy compositions / chemical compositions. 

This typically limits the production of the cleanest types of alloys with extreme low content of Fe, Cr, Zn, Cu and various trace elements..

Price

Making recycled aluminium requires only a fraction of the energy of making a primary ingot thus recycled aluminium is typically slightly more expensive than primary ingot due to cost of the separation and recycling system.

Links

Check out more at:

  • Hydro.com – link to Hydro’s recycled materials
  • Alumeco.com – link to Alumencos recycled materials. Note that they offer both recycled options and primary ingot made by green/renewable energy sources.
CO2 reduction

Conversion of CO2 Emissions/Kg to CO2 Emissions/m^3

CO2/m^3 reflects material replacements and CO2 emission reduction hereof.

Data was gathered and converted to m^3 and grouped into categories by RD8. Sources: A) Greenhouse gas emissions and natural capital implications of plastics (including biobased plastics) - (refers to Ecoinvent database, version 3.6 (7)); May 2021; European Topic Centre on Waste and Materials in a Green Economy. B) Stainless Steel and CO2: Facts and Scientific Observations, 29 March 2019, International Stainless Steel Forum (ISSF). C) WARM Version 13; March 2015; U.S. Environmental Protection Agency. D) Report: Emission factors in kg CO2-equivalent per unit, City of Winnipeg, Canada. E) Life cycle inventory databases; 2021; University of Waterloo, ON, Canada.

When looking up CO2 emissions per kg of material, e.g., Nylon and aluminum look alike (have similar values), but aluminum is far denser than nylon; hence replacing a volume of aluminum with a volume of nylon is actually CO2 friendly.

 

By looking at the various materials and their CO2 emissions/kg, the difference between them is minimal. However, when comparing the materials CO2/m^3 emission, it states that the emission per volume is much higher than the emission per kg. 

By evaluation of the desired product part characteristics the material selection can be optimized for CO2 – e.g. strength per CO2 emissions equivalent or stiffness per CO2 emissions equivalent.

To make it easy or for an initial screening CO2 emissions/kg is converted to CO2 emissions/m^3. This indication if one product part of a given physical size is replaced by an equivalent sized part of a different material – what would the CO2 emission reduction or increase then be.

Material Substitution

CO2 emissions/m^3 for various materials grouped into categories: virgin, recycled and biobased

Data was gathered and converted to m^3 and grouped into categories by RD8. Sources: A) Greenhouse gas emissions and natural capital implications of plastics (including biobased plastics) - (refers to Ecoinvent database, version 3.6 (7)); May 2021; European Topic Centre on Waste and Materials in a Green Economy. B) Stainless Steel and CO2: Facts and Scientific Observations, 29 March 2019, International Stainless Steel Forum (ISSF). C) WARM Version 13; March 2015; U.S. Environmental Protection Agency. D) Report: Emission factors in kg CO2-equivalent per unit, City of Winnipeg, Canada. E) Life cycle inventory databases; 2021; University of Waterloo, ON, Canada.

Replacing one cubic of material can lead to CO2 reductions. For example, going from stainless steel to steel can reduce CO2 emissions by about 70%, and going from virgin aluminum to reused aluminum reduces the CO2 emission by 89%.

 

The two examples indicate that there is a huge potential in reducing CO2 by changing to greener alternative materials.

Plastics

Material substitution can lead to CO2 reductions by use of biobased or recylcled plastics

Data was gathered and converted to m^3 and grouped into categories by RD8. Sources: A) Greenhouse gas emissions and natural capital implications of plastics (including biobased plastics) - (refers to Ecoinvent database, version 3.6 (7)); May 2021; European Topic Centre on Waste and Materials in a Green Economy. B) Stainless Steel and CO2: Facts and Scientific Observations, 29 March 2019, International Stainless Steel Forum (ISSF). C) WARM Version 13; March 2015; U.S. Environmental Protection Agency. D) Report: Emission factors in kg CO2-equivalent per unit, City of Winnipeg, Canada. E) Life cycle inventory databases; 2021; University of Waterloo, ON, Canada.

RD8 RES can systematically enable changes from virgin material to biobased- or recycled alternatives and in most cases reduce CO2 emissions by more than 20%.

 

For example, it is possible to save 79% by changing from PS to PS bio alternative

 

Some product types are mainly made of plastic parts therefore a special plot for these.

Reach out to us at RD8@RD8.tech for more information about how we together systematically can turn your products green

Robustness Philosophy

Axiomatic design & classic robust design on top of a foundation of kinematic design.

Design for sensitivity, complexity reduction and decoupling – based on a kinematic design foundation.

RD8 Robust Design Philosophy