60% is pretty low for PET, Glass isn't recycled perfectly either, but is generally better than PET.
In Switzerland 82% of PET is recycled. (Note that this number is the percentage that is really reused. Not the percentage that is collected.) The same number for glass is 96%. That means only 44% of glass gets recycled 20 times.
However, this is for reuse, not recycling. Not many glass bottles get reused, most get recycled. Recycling glass is less energy efficient than reusing.
> According to this paper, glass bottles need to be recycled 20 times in order to reach the same CO2 footprint as a PET bottle
This does not support the OP's case that "Glass is heavier and causes more CO2 emissions because of the increased energy use for transporting them."
There is going to be plenty of transport taking place during those 20 cycles of use and recycle. If the main energy cost of glass is in transport, as he asserted, that's only going to make it less competitive vs. plastic as the number of cycles increases.
The quote is inaccurate. The paper talks about glass bottle _reuse_.
As long as transport + washing cost of glass bottles are less than production + transport cost of plastic bottles there will be some number of reuses that make glass the winner.
60% recycling rate for PET bottles sounds very low compared to the 90% in Finland [1]. The deposit we have on plastic bottles ranges from 0.10€ to 0.40€ depending on the bottle size (the most common 0.5 ltr bottle has a deposit of 0.20€). Cans are recycled at an even higher rate of 95%.
In Switzerland 82% of PET is recycled. (Note that this number is the percentage that is really reused. Not the percentage that is collected.) The same number for glass is 96%. That means only 44% of glass gets recycled 20 times.
However, this is for reuse, not recycling. Not many glass bottles get reused, most get recycled. Recycling glass is less energy efficient than reusing.
http://www.swissrecycling.ch/wissen/kennzahlen-und-quoten/