Page 28 - Plastics News May 2019

FEATURES

Four strategies to tackle the carbon footprint

Prachi Patel
A study shows that an aggressive implementation of multi-layered strategies would be needed in order to
curb the greenhouse gas emissions

new study published in Nature Climate Change of global emissions. If things continue as is, this could go up
Aexplores ways to cut the carbon footprint of plastic. to 6.5 gigatons, or 15 percent of the global carbon budget,
In it, researchers from the University of California, by 2050 when yearly plastic production is expected to be
Santa Barbara say that reducing the carbon emissions over 1,600 megatons.
from plastics would require four strategies at “an Reducing plastic demand would cut emissions, especially
unprecedented scale and pace”: The use of renewable if combined with renewable energy. But this is going to
energy, biologically-derived biodegradable plastics, more
recycling, and reducing the demand for plastic. EH GLIÀFXOW DV SRSXODWLRQ DQG LQFRPHV ULVH DURXQG WKH
world. Recycling might be the most straightforward way
to cut emissions, the researchers found. Recycling all
plastic waste would reduce carbon dioxide equivalent
emissions to 4.9 gigatons in 2050, or 25 percent from
business-as-usual emissions. The impact of corn- and
VXJDUFDQH EDVHG SODVWLF RQ HPLVVLRQV LV FRPSOH[ :KLOH
completely replacing petroluem-derived plastics with
bio-based plastics would reduce global greenhouse gas
emissions, composting or burning waste bio-plastics can
put those emissions back into the air. Recycling bio-plastics
would reduce emissions, but not any more than recycling
conventional ones, the researchers’ calculations showed.

Switching to renewable energy “shows the greatest
potential” to reduce GHG emissions, Zheng and Suh
found. Using renewable energy to produce plastic would
halve the greenhouse gas emissions in 2050, even if the
plastics are made from petroleum. But emissions would
still be twice that of 2015 levels because of rising demand.
Global plastic production has skyrocketed in the past Reducing overall emissions would require much more than
few decades. The world produced about 400 megatons renewable energy. Recycling all waste plastics and using
of plastic in 2015. Only 18 percent of plastic waste is 100 percent renewable would give 77 percent, 84 percent
UHF\FOHG DQG DERXW SHUFHQW JRHV WR ODQGÀOO :KLOH and 86 percent reductions in greenhouse gas emissions
the impact of plastics on the ecosystem and human from fossil fuel-, corn- and sugarcane- based plastics,
health have been studied, little attention has been paid respectively. In the end, the most drastic reduction in
to the materials’ impact on climate change, Jiajia Zheng greenhouse gas emissions of plastics—93 percent from 2050
and Sangwon Suh write. So the duo set out to analyze levels, or 0.5 gigatons carbon dioxide equivalent—came
greenhouse gas emissions from the production of ten fossil from using only sugarcane-based plastics with 100 percent
IXHO EDVHG DQG ÀYH ELR EDVHG SODVWLFV DQG HYDOXDWHG KRZ renewable energy, recycling all plastic waste, and reducing
to lower those emissions. Every stage of plastic production the growth in plastics demand. “Our study shows that an
emits greenhouse gases: producing resin from petroleum, aggressive implementation of multi-layered strategies
making products from the resin, and disposal of plastic at would be needed in order to curb the [greenhouse gas]
the end of its life.
emissions from plastics,” the researchers conclude.
Their calculations show that the plastic produced in 2015
using conventional fossil fuels gave rise to 1.8 gigatons of Source: Jiahia Zheng and Sangwon Suh. Strategies to reduce the global
carbon dioxide equivalent, which amounts to 3.8 percent carbon footprint of plastics. Nature Climate Change, 2019.

Plastics News May 2019 28