Improving the environmental footprint for materials industries — plastics as well as steel, aluminum, cement and even food production — is crucial to achieving global climate goals, according to a new report from the United Kingdom-based Ellen MacArthur Foundation.
The foundation said in its Sept. 23 report "Completing the Picture: How the Circular Economy Tackles Climate Change," that greener production of materials in those industries could help the world achieve 45% of the greenhouse gas emission reductions needed to meet United Nations climate goals.
In effect, the report says that switching all energy to renewables will not be enough. It would only get 55% of the way to meeting the 2050 net zero emissions goals of the Paris Agreement.
More environmental production methods would reduce greenhouse gas emissions by 9.3 billion tonnes annually by 2050, equivalent to eliminating the current emissions from all forms of transportation, it said.
"Switching to renewable energy plays a vital role in addressing climate change, but this alone will not be enough," said Ellen MacArthur, founder of the group. "In order to achieve targets on climate, it is critical that we transform how we design, make, and use products and food."
The Paris Agreement says net zero emissions are needed to limit the global temperature increase to 1.5º C.
The four materials industries that the report focuses on — cement, steel, plastics and aluminium — account for 60% of emissions from industry, which overall is responsible for 21% of global greenhouse gas emissions.
The foundation said switching to greener methods of making cars, clothes, food and other products is an opportunity for industry.
"Carbon constraints actually represent huge ingenuity opportunities," said Christiana Figueres, former executive secretary of the United Nations Framework Convention on Climate Change, in a statement released by the foundation. "This report offers compelling figures to give confidence in our ability to optimise decarbonisation and economic development in mutual support of each other."
The report gave some specific examples of how switching production methods for plastics could reduce carbon emissions.
It said, for example, that using renewable feedstocks for items such as bio-based plastics has the potential to bind carbon in products or in effect become a carbon sink.
While 1.8 kilograms of carbon dioxide is released to make each kg of fossil-fuel based polyethylene, the report said making a kg of bio-based polyethylene has the potential for negative emissions, in effect reducing 2.2kg of carbon dioxide emissions per kg of bio-based PE.
As well, it said recycling 1 metric ton of plastics can reduce CO2 emissions by 1.1 to 3 tonnes compared with producing the same amount of virgin plastics.
"The use of recycled materials reduces the demand for virgin materials, while the processing of recycled aggregates can generate 40-70% fewer CO2 emissions compared to virgin aggregates," the report said.
It said that reusing recycled materials could remove 1.7 billion tonnes of CO2 per year by 2050, with the report assuming a 28% recycling rate for plastics overall from mechanical processes and 21% from chemical recycling.