When the system was initially implemented, usage dropped approximately 40% to 50%, eliminating the prints that previously went into the garbage and recycling cans. If the system encourages individuals to print more conservatively, it is likely that it will eliminate the need for over 5 million prints. Even though the university uses recycled paper, reducing the number of prints by 5 million will save several hundred trees.


Environmental Implications of Reduced Paper Consumption from Intelliprint System

We used the following assumptions to calculate the number of trees theoretically "saved" by not using 5,400,000 sheets of Springhill Relay, as well as some other environmental effects.


Assumptions:
  1. The paper was manufactured at our Riverdale mill in Selma, Alabama. Manufacturing data from this mill are used in these calculations.
  2. The Springhill Relay 30% post-consumer waste (PCW) paper contains 72.5% recycled and virgin fiber on average, and approximately 27.5% non-fiber components, including starch, filler and moisture. Since the 30% recycled fiber originally came from trees, we used the 72.5% to represent total wood fiber. You could take the position that the total number of newly cut trees used to make the product is less if you account for the 30% PCW in the paper, but we didn't make that assumption for the purpose of this analysis.
  3. All fiber used to manufacture this paper is harvested from plantations of loblolly pine. There may be a small percentage of other species, but we used this one tree to simplify the analysis.
  4. The average pine harvested is 10 inches in diameter at breast height (dbh). We used this diameter instead of the 7 to 8 inches because 10 inches is the average size tree at our pulp mills. Growth studies still underway suggest that 5.3 trees of this size are required to produce 1 bone-dry (0% moisture) ton of fiber for paper.
  5. For the purpose of this analysis, we pretend that the paper does not come from managed forests (if we don't make this assumption, there would be no trees to save, since without the product we would not have planted the trees in the first place).

Basis for Calculations:

Sheets per box = 5,000
Boxes per pallet = 40
Sheets per pallet = 200,000
Pounds per pallet = 2,000


Analysis:

Step 1:
We first need to calculate how much wood fiber there is in 1 pallet or 1 ton of paper product. Each pallet can hold 2000 pounds of paper. We can use the fiber content of the paper (72.5%) to calculate how much fiber is in one ton of product, or one pallet of product.
  • One pallet or one ton of product (200,000 8.5" x 11" sheets of Springhill Relay) contains 1,450 pounds of bone-dry fiber. [ 1 pallet = 2000 pounds of paper]

    2000 pounds of paper x 0.725 = 1,450 pounds of fiber per ton of paper or per pallet

Step 2:
From assumption #4, we know that forest growth studies suggest that it takes approximately 5.3 loblolly pine trees (at 10" diameter) to produce 1 ton of bone dry fiber. Since we now know that there are 1,450 pounds of bone dry fiber in one ton of paper or one pallet, we can convert the pounds to tons and multiply this by the number of trees (5.3) to figure out how many trees it takes to make one ton of paper product or one pallet of product.
  • One pallet of paper = 3.84 trees

    (1,450 pounds x 5.3)/2000 = # trees per pallet = 3.84

Step 3:
Now that we know how many trees go into one ton of paper product or one pallet, we can use the estimates from your paper reduction program (45% decrease in consumption, saving 5,400,000 sheets, 27 tons or 27 pallets) to determine how many trees would not be used.
  • Decreasing consumption of paper by 27 tons will save 103.68 trees.

    3.84 trees/pallet x 27 pallets = 103.68 , or

    1,450 pounds fiber/pallet x 27 pallets = 39,150 pounds of fiber or 19.6 tons of fiber x 5.3 trees/ton of fiber = 103.88 (rounding difference)


The 103.68 trees represent approximately 1/5 of an acre of trees when planted as seedlings, or approximately 1 acre of mature loblolly pine trees when harvested around the age of 25 years (the stand is thinned 1-2 times during the growth cycle, leaving approximately 120 trees per acre for the final harvest).


Some Other Environmental Implications:

Approximately 35.1% of printing and writing papers are recovered for recycling after use, diverting paper from the landfill. (American Forest & Paper Association's Recovered Paper Statistical Highlights, 1998)

The paper not purchased (27 tons or 5.4 million sheets) would have required the mill to use 602,451 gallons of water and 894.5 million BTU of energy to manufacture.

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