Friday, March 23, 2012

Plastics - Green Washing Recycling

The increasing media attention to plastic pollution is an encouraging sign.  One by one cities are implementing plastic bag bans or use fees.   The plight of the oceanic garbage patches have reached mainstream media.   But plastic consumption is still rising, one study estimates that by 2015 individual usage in North America and Europe will increase by 40%, in Asia it is closer to 50%.  We already have a major plastics problem, so what are we to do with all this additional plastic?

By now, everyone has heard of the 3 R's, but it seems more attention, even by major environmental groups, is being paid to the third and last R – RECYCLE.  On a recent trip to The National Zoo, I noticed the following “informational” trash can:

Doesn’t it give you the warm fuzzies?  “Look ma, it’s OK to buy plastic water bottles because look at how much energy we are saving by recycling!”  So that got me thinking, aren’t  they just green washing the truth?  Why not tell us how much energy we can save by reusing and NOT buying and recycling a single-use plastic bottle.

I thought this would be an easy task, but after scouring the internet for a few hours, I found only one study that attempted to estimate the energy required to produce plastic (PET) water bottles.   

The 2009 Pacific Institute report, Energy Implications of Bottled Water (, breaks down the energy required for each phase of production.  Their findings show that it takes 5.6 – 10.2 MJ of energy to manufacture, treat, fill, and transport for a single 1 L plastic water bottle.  In comparison, tap water takes 0.005 MJ/L to produce.

Energy intensity (MJth/ L)
Manufacture plastic bottle
Treatment at bottling plant
Fill, label, and seal bottle
Transportation: range from three scenarios

So how does that compare to our sign claiming recycling a single bottle can power a 60-watt bulb for 6 hours?  If we take the average of the energy required from the study, 7.9 MJ/L, and convert that to watt-hours (1 watt-hour = 3600 J), you can power a single 60-watt light bulb for approximately 37 HOURS

Extrapolating by assuming that every American uses 200 plastic bottles/year, that is equal to powering a 60-watt bulb for 308 DAYS

Unlike most of our plastic problems, this solution is easy: bring and refill your own reusable bottle.  So why are we not advocating that little fact more?