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[GreenYes] Re: Energy Calculations

Title: [GreenYes] Re: Energy Calculations

According to the plastics manufacturing industry, it takes around 3.4
megajoules of energy to make a typical one-liter plastic bottle, cap,
and packaging. Making enough plastic to bottle 31.2 billion liters of
water required more than 106 billion megajoules of energy. Because a
barrel of oil contains around 6 thousand megajoules, the Pacific
Institute estimates that more the equivalent of more than 17 million
barrels of oil were needed to produce these plastic bottles.

Benefits of Aluminum Recycling
The average aluminum can contains 40 percent postconsumer recycled
aluminum. Recovering aluminum for recycling saves money and
dramatically reduces energy consumption. The aluminum can recycling
process saves 95 percent of the energy needed to produce aluminum from
bauxite ore, as well as natural resources, according to the Aluminum
Association. Making a ton of aluminum cans from virgin ore, or
bauxite, uses 229 BTUs of energy. In contrast, producing cans from
recycled aluminum uses only 8 BTUs of energy per can.

An aluminum can that is recovered for recycling is back in the
consumer stream in a short period of time. It takes about 6 weeks
total to manufacture, fill, sell, recycle, and then remanufacture a
beverage can. Most of the aluminum recovered from the waste stream is
used to manufacture new cans, "closing the loop" for can production.

Recycling saves 50% of the energy needed to make products from new

Here's a file I have on the plates question:

The MN Pollution Control Agency has done some extensive research and
marketing on product packaging.  They list some of the info on their

CAFETERIA SERVICE, REUSABLE CUPS--Switching from single-use drink cups
to reusable plastic cups, the freshman dining hall reduces annual
operating costs for this single food item by 95%, saving $186,500.
Go to

I received the same question from a high school student a few years
ago.  THE Wastewise help line 800 EPA-WISE (372-9473) sent me some
studies, it might be good to call them and give them the numbers for
the school and they will give you the waste and cost comparisons.  One
of the studies Wastewise sent me from the Itsaca Medical Center in
Grand Rapids, MN ( published in a document by the MN office of Waste
Mgmt.) was on changing from single use plates to reusable plates.
Here is what they found,  on an annual basis using 72 reusable plates
vs 64 cases of disposable plates.

cu yd = cubic yards
cu in = cubic inches

Single Use  Plates              Reusable  Plates                Waste or cost reduction using
reusable plates

Waste Volume            2,252,800 cu in/yr              510 cu in/yr
2,252,290 cu in or 39.8 cu. yd  ( 99.9% reduction)
Waste weight              1280 lb/yr                         8.4 lb/yr                          1,272 lb/yr  (99 %
weight reduction)
Cost                       $2,304/yr              $146 ( including washing costs)        $2,158  (94%
cost reduction)
Number used             32,000/yr                       72 in 3 years                    31,976/yr

Payback period - it was calculated that the payback period for buying
the reusable plates would be 39 days.  After that time the Medical
Center will save $2,209 per year for the remainder of the life of the

Dear JTRnetters:  I have received an inquiry from a school teacher
requesting concrete information about the environmental impact of
polystyrene tray use in their school cafeteria versus reuse of plastic
trays.  The school already has the reusable ones, but has abandon them
for the disposable.  In looking at JTR net and NWPC archives, I can
find  information on how to locate recycled content plastic trays and
evaluation of disposable poly versus disposable molded paper trays,
but no information regarding disposable poly versus reusable plastic.
Can anyone help steer me to a resource that can assist this teacher in
his plight? This is a school, but resources for food service reuse of
any kind would likely be helpful.  In advance, thanks.

On Sep 25, 2:37 pm, "JON TULMAN" <Jon.Tul...@no.address>
> A resident in our county is looking for information on the following:
> 1.  Energy input to make from virgin stock a plastic water or soda bottle versus making an aluminum beverage can;
> 2.  Energy input comparison to recycle each of the above;
> 3.  Energy input on using disposable paper plates versus washing dishes.
> I realize that these are pretty broad questions with many variables.  Nevertheless, if you have any data youself or can point me to a website, I'd appreciate it.
> If you prefer to answer me directly instead of to the listserve, please respond to:   jon.tul...@no.address
> Thanks.
> Jon Tulman
> Associate Planner
> Eau Claire County (Wisc) Planning Department
> 1-715-839-6190

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