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[greenyes] RE: Env Benefits of Recycling

I have to agree with John Reindl on this. Your description of multiplier effects is confusing, and can lead people to a wrong conclusion about the energy savings on recycling glass.  You state that at the amount of energy saved by recycling glass at an 80% rate is five times larger than the energy saved per single use of 80% recycled glass, **when considered over the live of the recycled glass**.  Well, that is true, but only because you are looking at the total energy savings over a period 5 times as long.  In fact though, if recycling 80% of the glass produced about a 20% energy savings over 1 year, it will still produce a system-wide energy savings of about 20% over the five year average "lifetime" of the glass.  The absolute savings might be five times greater over 5 years than over 1 year, but the savings per year (or per bottle manufactured) is still only 20%.

If people get confused by this multiplier effect, they might wrongly reach a conclusion that it is more important to get recycled content into products that can easily be recycled than it is to get recycled content into difficult-to-recycle products.  In fact, this is not true.

Let's take the example of glass bottles (easy to recycle) and fiberglass (hard to recycle).  Let's presume for the moment that there are important reasons for making fiberglass even though it is hard to recycle.  After all, fiberglass serves as insulation that results in much more energy savings than the energy used in fiberglass manufacture.  Let's also presume that the energy savings resulting from using recycled content in the manufacturing of glass are roughly the same whether you are making bottles or fiberglass out of the glass cullet.

Consider a city with both a fiberglass plant and a glass bottle plant.  Both plants are the same size, producing 100,000 tons of glass product per year.  Say that this is in a bottle bill state, so that 80% of the glass from the bottle manufacturing is recycled and available to make new glass.  Which of the following scenarios would use more energy?

Scenario 1) the bottle-making plant makes bottles out of 80,000 tons of cullet and 20,000 tons of virgin material each year.  The fiberglass plant uses 100,000 tons of virgin material, and no recycled cullet.

Scenario 2) the bottle-making plant uses 100,000 tons of virgin material and no recycled cullet.  The fiberglass plant uses 80,000 tons of bottle cullet and 20,000 tons of virgin material.

A person could easily think that because of the "multiplier effect", scenario 1 will save much more energy, because the glass in each bottle gets recycled 5 times before being disposed, whereas in scenario 2, the recycled glass will eventually be disposed with a single use.  In fact though, both scenarios will end up using exactly the same amount of energy, the same amount of cullet, and the same amount of virgin material as each other.  There is no environmental benefit of keeping the recycled glass in a recyclable product if doing so forces the greater use of virgin material for the non-recyclable product.

Peter Spendelow
Oregon Department of Environmental Quality
>Date: Tue, 4 Nov 2003 16:17:01 -0500
>To: "Reindl, John" <Reindl@no.address>, <greenyes@no.address>
>From: "Jeffrey Morris" <jeff.morris@no.address>
>Subject: RE: Env Benefits of Recycling
>But if we're talking about a system where glass is all disposed all the time
>versus a system with an 80% glass recycling rate, then the difference in
>energy and environmental benefits of a glass container over its life cycle
>is indeed five times greater than the benefits from just recycling that
>glass container (or a ton of cullet) once.  That's what I understood the
>debate to be about on This American Life - whether glass recycling is worth
>it.  The difference in life cycle energy and environmental benefits between
>the dispose-all-glass-all-the-time waste management system and the
>recycle-glass-at-80% waste management system is 5 times greater then the
>numbers that were discussed on This American Life, because those were the
>benefits from recycling a glass container or a ton of cullet just once.  The
>disposal-all-glass-all-the-time system throws away 5 times as much in energy
>and environmental benefits versus the 80% recycling system.

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