Polyethylene terephthalate (PET) is the workhorse polymer of packaged water. Its clarity, strength, gas barrier, and food contact safety are hard to beat, which is why virtually every packaged water brand in India uses it. What most consumers do not know is that PET can be made from sugarcane instead of petroleum, with no change in the final polymer.
The Chemistry
PET is a polyester made by condensing two monomers.
- Monoethylene glycol (MEG) which accounts for about 30 percent of PET's mass by weight.
- Purified terephthalic acid (PTA) which accounts for the remaining 70 percent.
Bio PET typically means PET where the MEG has been produced from sugarcane ethanol instead of fossil ethylene oxide. Because the polymer structure is chemically identical, bio PET drops straight into existing PET recycling streams without contamination. This is a critical operational win over fully bio derived polymers that need separate collection.
Carbon Footprint
A comparative cradle to gate life cycle assessment (Franklin Associates 2020, updated 2023) shows.
- Fossil PET resin: 2.15 kg CO2e per kg of resin.
- 30 percent bio PET (bio MEG, fossil PTA): 1.58 kg CO2e per kg. About 26 percent lower.
- 100 percent bio PET (bio MEG plus bio PTA, still emerging commercially): 0.75 kg CO2e per kg. About 65 percent lower.
The carbon saving comes primarily from two sources. The sugarcane crop captures CO2 during growth (biogenic carbon), and bio MEG production avoids the energy intensive steam cracking process used to produce fossil ethylene oxide.
Mechanical Properties
Because bio PET is chemically identical to fossil PET, every mechanical property matches: tensile strength, elongation at break, gas barrier, thermal stability, and clarity. Coca Cola's PlantBottle programme has been shipping 30 percent bio PET globally since 2009 with no consumer complaints about bottle performance.
What Bio PET Is Not
Bio PET is not biodegradable or compostable. Despite containing plant derived material, it does not biodegrade faster than conventional PET because the polymer structure is identical. If biodegradability is a priority, look for IS ISO 17088 certified PHA or PLA based packaging instead, which Green ORA also offers.
Our Recommendation
For brands seeking lower carbon packaging without any operational complexity or food contact risk, bio PET is an excellent choice. For brands in applications where end of life fate is uncontrolled (outdoor events, festival hospitality), certified compostable packaging is preferable. Many customers choose both, depending on the use case.