In this guide, we outline whether aluminum might be more sustainable than plastic, and vice versa.
This guide compliments our separate guide comparing the sustainability of metals and plastic.
Summary – Is Aluminum More Sustainable Than Plastic?
Refer to the linked guide above for a general sustainability assessment of metals vs plastic
However, some specific sustainability considerations for aluminum can be found below
Aluminum can be used in a range of products and items such as bottles, cans, containers, windows and doors, and more.
There has to be some consideration for what the product is, and how it’s used when assessing sustainability
Each product may have a different sustainability footprint because of the variables involved with each of them … such as how long it lasts, how easy it is to recycle, and so on
The sustainability indicator being measured should also be identified and considered, as sustainability ratings can vary for different indicators.
Using one example of comparing an aluminum product with a plastic product, an aluminum bottle that is re-used hundreds of times might be more sustainable in some ways than a single use plastic bottle
Aluminum vs Plastic: Sustainability Comparison
General Sustainability Of Aluminum
Across a range of different products, some of the general sustainability considerations might be …
– Depletion of resources may not be a major concern
Aluminum comes from bauxite, and bauxite might be considered an abundant resource
But, the mining of bauxite may result in some environmental side effects
… [aluminum] comes from bauxite and depletion of resources is not really a concern (greenlifestylemag.com.au)
[Bauxite mining can cause some environmental concerns] (earth911.com)
– Energy consumption and carbon emissions at the production stage may be a concern
Aluminum production is one of the most energy intensive industries, and this can equate to significant carbon emissions too
Aluminum is reported to be more energy intensive than stainless steel production by some sources
Although, over half of all aluminum production is powered by hydroelectricity according to some reports
Additionally, energy consumption and the carbon footprint of aluminum production may be coming down over time
Aluminum takes approximately ‘13,500 to 17,000 kWh per ton’ to make (treehugger.com)
‘55% of world aluminium production is powered by renewable hydroelectric power’ (as opposed to fossil fuel powered production processes) (duration.co.uk)
In the last 40 years, energy requirements to produce aluminum, and the carbon footprint, are both improving (aluminum.org)
Aluminium production is one of the most energy-intensive industries [which may lead to greenhouse gas emission concerns if electricity comes from fossil fuels] (greenlifestylemag.com.au)
– Using recycling aluminum material may save energy and cut carbon emissions
Using recycled aluminum material for new products may save energy and cut carbon emissions compared to using only new material (from virgin material) for new aluminum products
recycling.world-aluminium.org indicates that recycled post consumer aluminum saves CO2 and electricity:
Today, recycling of post-consumer aluminium products saves over 90 million tonnes of CO2 and over 100,000 GWh of electrical energy, equivalent to the annual power consumption of the Netherlands.
Through the recycling process it saves 95% of the energy that it would cost to produce new aluminum (azahner.com)
Using recycled aluminum cans instead of raw material may use ‘five percent of the energy and [generate] five percent of the emissions’ [with] carbon emissions [being 96% less overall]
– Recycling aluminum isn’t always 100% friendly
‘[… there are] alloys that have to be removed using chemicals like chlorine; there are fumes and chemical releases that are toxic’ (treehugger.com)
– Relying on recycling aluminum has it’s own problems to consider. Cutting consumption of aluminum may need to be part of future strategies
According to treehugger.com, recycling aluminum reduces energy requirements but we should also be focussing on reducing consumption for some of the following reasons: …
… because ‘recycled aluminum creates the demand for more virgin aluminum and more environmental destruction’
[The recycling of aluminum isn’t 100% eco friendly because it can involve chemicals like chlorine, which can have toxic and hazardous effects]
[In the] future … there [may not be] enough recycled aluminum to meet demand
Aluminum mining (of bauxite) can be destructive, and then bauxite has to be shipped to another country
– Micellaneous notes on the general sustainability of aluminum
[Aluminum may be abundant as a resource, and when used in products, may be long lasting and endlessly recyclable] (duration.co.uk)
Aluminum is generally a green building material (aluminum.org)
As a general measure of aluminum’s energy consumption compared to steel: ‘Aluminum has [a] 20 percent smaller life cycle energy consumption than steel in transportation’ (aluminum.org)
Plastic vs Aluminum Materials & Products In General
Aluminum has a high recycling rate as a material compared to plastic, and aluminum can be truly closed loop in terms of being able to be recycled back into itself.
Aluminum cans are an example of this
recycling.world-aluminium.org indicates that using recycled post consumer aluminum is a repeatable process:
[The fact that aluminum is infinitely recyclable] has led to a situation where today around 75% of the almost one billion tonnes of aluminium ever produced is still in productive use
– Plastic in the environment may lead to several environmental problems that aluminum may not
Some of these problems may include breaking down into microplastics, leaching chemicals and additives from the plastic material (depending on the type of plastic), and absorbing organic pollutants (POPs)
Plastic vs Aluminum Cans
– The recycling of aluminum cans involve chemicals like chlorine to process/remove the alloys in the metal
Chlorine has potential to be toxic or release fumes
– There may be some concerns around the lining of aluminum cans and bottles
It may contain BPA like plastic does
– Aluminum as a material used in bottles or cans may have a higher carbon footprint than glass, plastic, and tetra pak
Plastic vs Aluminum & Tin In General & Specifically As A Packaging Material
desjardin.fr compares the sustainability of plastic to aluminum and tin as a packaging material, and found that each material has sustainability benefits and drawbacks:
[Plastic may use less energy and emit less CO2 during production than aluminum and tin]
[Only a fraction of the energy is used in plastic production compared to aluminum and tin]
[In terms of carbon emissions …] When the production process for each is compared it is found that 1 kg of Polyethylene plastics produce around 4 kg CO2 and 1 kg aluminum produces 10.63 kg CO2
[Aluminum is an abundant resource, doesn’t take as long as plastic to break down, doesn’t have the leaching issues and environmental issues like breaking down into microplastics, has a better recycling rate, and the recycling of aluminum and tin allows less energy and CO2 to be used and emitted in their production process]
[On the recycling rate of aluminum and tin: …] ‘In 2009 the EU had a recycling rate of 72% for tin and aluminum – compared to 9% of all plastic is recycled in the US]
[On the energy savings and emissions reductions from recycling aluminum and tin: …] ‘When tin and aluminum are recycled it allows for less new metal to be extracted from their ores. This reduces the amount of energy used annually on the production of aluminum and tinplate packaging. Due to this large recycling effort the amount of CO2 created in the production process is only 1/3 of what it would be if new ore were being continually extracted’
The Sustainability Of Plastic
Read more specifically about the sustainability of plastic in this guide.
Other Factors To Consider
– Just as there are different types of plastic, there are different types of aluminum
– Each different type of aluminum can have a different sustainability footprint (depending on how it’s processed, fabricated, etc.)
– The waste management systems, facilities and technology in a given country or State make a difference to the sustainability not just of different materials, but different waste items and products
This is because of how different waste materials and items are processed among the different disposal options at different rates
– How long an aluminum product or item lasts, or how many times it can be used/re-used before being thrown out, impacts it’s sustainability footprint
One example is aluminum cans for soda and alcohol, and another example is aluminum window and door frames used in construction.
Aluminum window frames may have a much longer lifespan than aluminum cans
– There are different types of aluminum products with different sustainability footprints, and the same is true for plastic
One examples is aluminum vs plastic window frames.
Specifically with aluminum vs plastic frames, there can be considerations to do with the insulation and energy efficiency of each too, which each have a sustainability footprint from a construction materials sense