Carbon Storage & Low Energy Intensity in Harvested Wood Products
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Transcript of Carbon Storage & Low Energy Intensity in Harvested Wood Products
Carbon Storage and Low Energy Intensity in Harvested Wood
Products: Critically Important in Developing a Rational Carbon Trading
Policy
Current carbon protocols under the Kyoto accord award credit only for establishment of new
forests on previously non-forested land.
Current carbon protocols under the Kyoto accord award credit only for establishment of new
forests on previously non-forested land.
However, proposed rules would provide credit (and payments) for “avoided deforestation.”
However, proposed rules would provide credit (and payments) for “avoided deforestation.”
The potential for reduced carbon emissions through use of wood rather than more energy intensive non-renewable alternatives is also gaining recognition.
The potential for reduced carbon emissions through use of wood rather than more energy intensive non-renewable alternatives is also gaining recognition.And carbon storage is likely to become an important issue in the green bldg movement.
Material
Net Carbon
Emissions (kg C/metric ton)
Framing lumber 33
Medium density fiberboard (virgin fiber)
60
Brick 88
Glass 154
Recycled steel (100% from scrap)
220
Concrete 265
Concrete block 291
Recycled aluminum (100% recycled content)
309
Steel (virgin) 694
Plastic 2,502
Aluminum (virgin) 4,5321/ Values are based on life cycle assessment and include gathering and processing of raw materials, primary and secondary processing, and transportation. 2/ Source: USEPA (2006).
Net Carbon Emissions in Producing a Ton of: 1/ 2/
Dimension lumber wood
joist floor
Concrete slab floor
Steel joist floor
Total 9.93 24.75 48.32
Consumption of Fossil Fuels (MJ/ft2) Associated with Three Floor
Designs
Source: Edmonds and Lippke (2004)
Results of a Life-Cycle Inventory of a Large Office
Building Construction
Total Energy Use*
Above Grade Energy Use*
CO2 Emissions**
Wood 3.80 2.15 73
Steel 7.35 5.20 105
Concrete 5.50 3.70 132
Source: Athena Sustainable Materials Institute (1997)
* GJ x 103
** kg x 103
Building Element
Type of Exterior Wall
Lumber-Framed
Wall
Concrete Wall
Structural components 6.27 75.89
Insulation 8.51 8.51
Cladding 22.31 8.09
Total 37.09 92.49
Total Consumption of Fossil Fuels (MJ/ft2) Associated with Two
Exterior Wall Designs in a Warm Climate Home
Source: Edmonds and Lippke (2004)
CaCO3 CaO + CO2
limestone Δ lime carbon dioxide 2700°F
Production of Cement – Energy Intensive and a Major Source of
Carbon Emissions
↑
Material
Net Carbon
Emissions (kg C/metric ton)
Framing lumber 33
Medium density fiberboard (virgin fiber)
60
Brick 88
Glass 154
Recycled steel (100% from scrap)
220
Concrete 265
Concrete block 291
Recycled aluminum (100% recycled content)
309
Steel (virgin) 694
Plastic 2,502
Aluminum (virgin) 4,5321/ Values are based on life cycle assessment and include gathering and processing of raw materials, primary and secondary processing, and transportation. 2/ Source: USEPA (2006).
Net Carbon Emissions in Producing a Ton of: 1/ 2/
Material
Net Carbon Emissions (kg
C/metric ton)
Net Carbon Emissions Including Carbon Storage
Within Material (kg C/metric ton) 3/
Framing lumber 33 -457
Medium density fiberboard (virgin fiber)
60 -382
Brick 88 88
Glass 154 154
Recycled steel (100% from scrap)
220 220
Concrete 265 265
Concrete block 291 291
Recycled aluminum (100% recycled content)
309 309
Steel (virgin) 694 694
Plastic 2,502 2,502
Aluminum (virgin) 4,532 4,5321/ Values are based on life cycle assessment and include gathering and processing of raw materials, primary and secondary processing, and transportation. 2/ Source: USEPA (2006).3/ A carbon content of 49% is assumed for wood.
Net Carbon Emissions in Producing a Ton of: 1/ 2/
Carbon Dioxide Implications of
Forest Growth and Wood Use
Carbon Dioxide Implications of
Forest Growth and Wood Use
Tree growth sequesters considerable quantities of carbon
Dry wood is 49% by weight carbon. For each pound of carbon stored:
3.7 pounds of carbon dioxide are removed from the atmosphere
2.7 pounds of oxygen are produced Carbon is stored in the soil, the litter,
and in the trunks, branches, twigs, leaves, and roots of trees.
Carbon Dioxide Implications of Forest Growth and Wood
Use
Cumulative Changes in Carbon Stocks in Soil, Forest Litter, and
Standing Trees After Afforestation
0
50
100
150
200
250
300
0 10 20 30 40 50 60 70 80 90 100
Time (Years)
Cum
lula
tive
Car
bon
(tC/h
a)
Source: Marland and Schlamadinger (1999)
SoilLitter
Trees
Cumulative Changes in Carbon Stocks with Afforestation and
Subsequent Harvest After 40 Year Rotation
020406080
100120140160180
0 7
14 21 28 35 42 49 56 63 70 77 84 91 98
Time (Years)
Cum
ulat
ive
Car
bon
(tC/h
a)
SoilLitter
Trees
Source: Marland and Schlamadinger (1999)
The production of wood products can add significantly to stocks of stored carbon . . . especially when products have a long service life.
Homebuilding Activity in the United States in the 20th
Century
0
5
10
15
20
25
'10s '20s '30s '40s '50s '60s '70s '80s '90s
Million
s o
f U
nit
s
U.S. housing inventory 2000: 116 million units.
Cumulative Changes in Carbon Stocks with Afforestation and
Subsequent Harvest After 40 Year Rotation
020406080
100120140160180200
0
10
20
30
40
50
60
70
80
90
100
Time (Years)
Cum
ula
tive C
arb
on (
tC/ha)
Long-lived productsTreesLitterSoil
Source: Marland and Schlamadinger (1999)
Projected Change in Carbon Stocks in Ontario’s Forests,
2000-2100
050
100150200
250300350
400450
FMU PFL MeasFMZ
Parks WdProd
TotForest
2000-2020
2000-2050
2000-2100
Mill
ion
metr
ic t
on
s of
carb
on
Source: Colombo, S., Chen, J., and Ter-Milkaelian, M. 2007.
While some wood may be land-filled following processing, wood residues are more commonly burned to produce process steam or electricity.
Also, when wood products, rather than products made from alternative materials, are manufactured and used, emissions of carbon dioxide are minimized.
The use of wood, therefore, results in “carbon storage” in that emissions of carbon are less that what would otherwise have been produced.
Cumulative Changes in Carbon Stocks with Afforestation and Subsequent Harvest After 40 Year Rotation
0
50
100
150
200
2500
10
20
30
40
50
60
70
80
90
100
Time (Years)
Cu
mu
lati
ve C
arb
on
(tC
/ha)
Avoided Fossil FuelsLandfillShort-lived productsLong-lived productsTreesLitterSoil
Source: Marland and Schlamadinger (1999)
t Carbon
Summary
Neither carbon storage in wood nor avoided greenhouse gas emissions resulting from use of wood rather than alternative materials are considered in global carbon protocols.
The omission is serious, as both factors have a substantial impact on carbon storage and flux.
Whatever carbon protocol we adopt in Minnesota must, at a minimum, account for carbon storage in wood products.