Monday, January 18, 2010

Post # 11: Putting A Lid On Bottled Water ?

Do you ever wonder about the energy consumption and CO2 footprint of a bottle of that cold, clear, water you pickup from the local quick-mart on the way to/from your kid's soccer game?  I became curious about this recently after noticing a beautiful bottle of south-pacific water in my hotel room.

After some digging, I found a very interesting short paper by Gleick and Cooley of the Pacific Institute ( that analyzed this exact question (well.. the energy consumption part of it anyway).  The paper, entitled, "Energy Implications of Bottled Water," is available online at .

Gleick and Cooley analyzed three scenarios for bottled water consumed in the Los Angles area: (1) water locally bottled, (2) water bottled in Fiji, and (3) water bottle in France.  The paper concludes that, depending on the bottling location, the energy required to purify, bottle, and deliver 1 liter of cold, clear bottled water to the consumer's lips is between 5.6 and 10.2 MJthermal/liter. (The larger number is associated with water produced in Fiji.  The energy demand would be even larger for an east-coast USA consumer.

According to Gleick and Cooley, the US consumed approximately 33 million liters of bottled water in 2007.  So if we extrapolate to the total effective energy required to meet the US market, 33E6 liters * 10 MJthermal/liter = 330E6 MJthermal.

The effective carbon footprint of this bottled water depends, of course on the source of the thermal energy.  If we assumed ALL of the energy required came from coal, and assuming a conversion factor of ~ 0.38 kg CO2 / MJthermal, the total CO2 footprint of our bottled-water addiction is approximately 330E6 MJthermal * 0.38 kg CO2 / MJthermal = 125,400,000 kg CO2 or 125,400 MT CO2.  Recalling our total annual US CO2 emissions is approximately 6,000,000,000 MT  CO2, this represents approximately 0.002% of our total annual CO2 emissions.

Significant?  You be the judge...


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