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LIFE CYCLE ASSESSMENT FOR

BIOENERGY

Charles D. Ray

Life Cycle Assessment• A life cycle assessment (LCA, also known as life cycle

analysis, ecobalance, and cradle-to-grave analysis) is a

technique to assess environmental impacts associated with

all the stages of a product's life from cradle-to-grave (i.e.,

from raw material extraction through materials processing,

manufacture, distribution, use, repair and maintenance, and

disposal or recycling). LCA’s can help avoid a narrow outlook

on environmental concerns by:

– Compiling an inventory of relevant energy and material inputs and

environmental releases;

– Evaluating the potential impacts associated with identified inputs and

releases;

– Interpreting the results to help you make a more informed decision.

http://en.wikipedia.org/wiki/Life_cycle_assessment

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Energy in LCA

• Usually treated as an input from the

technosphere

– Technosphere is an ecological term describing

the novel human techno-ecosystems that are

economically engineered systems of the total

human ecosystem (or anthrome)

• Can be analyzed as independent process(es)

for energy analysis and comparison

But…

• Energy projects typically focus on energy

balances, efficiency, and economics

• “Carbon replacement” is the only ecological

concept typically considered in energy

projects

• The broader environmental impacts of

energy decisions are complex and not usually

considered

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AtmosphereEnergy

Conversion

Decay or

burned

without

energy

conversion

Forests

Roundwood

Lumber

Pallets

Disposal

Recycling

The Carbon Cycle of Wood Pallets

Adapted from Skog and Nicholson, 2000

GrowthHarvest

CO2

CO2

AtmosphereEnergy

Conversion

Decay or

burned

without

energy

conversion

Underground

Refining

Resin/Pellets

Pallets

Recycling

The Carbon Cycle of Plastic Pallets

Drilling

Disposal

CO2

CO2

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AtmosphereEnergy

Conversion

Decay or

burned

without

energy

conversion

Underground Refining

Resin/Pellets

Pallets

Recycling

Drilling /

Forests

Roundwood

Lumber

Pallets

Harvest

What’s the difference?

Carbon +

Carbon

Neutral

Disposal

CO2

CO2

CO2

How do the different treatment methods compare?

• Comparing Heat Treatment, Me Br Fumigation and RF Heating

“Life Cycle Analysis of pallet types and treatment methods” – Ray, et al 2010

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Why bioenergy?

• Assumed benefits for:

– Climate change impact

– Solution to peak oil

– Energy security

– Local economy

The need for scientific, not political,

evaluation of energy sources

“There is no shortage of energy

anywhere on earth that has not been

caused by government.”

- Michael T. Halbouty, world-renowned

oilman and geologist

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The need for scientific, not political,

evaluation of energy sources

“In 122 years, about 3.3 million oil wells have been drilled

into the planet’s crust. Of this number, 2.5 million were

drilled in the 48 continental states of the United States…The

rest of the world has been relatively unexplored, especially

formerly colonial nations of Africa and Asia.”

- Jude Wanniski, economist and author, The Way the World

Works

U.S. Wood Energy Potential

• By 1980 USDA estimate, 600 million dry tons/year of “unused” wood

• Using standard btu conversions, this is equivalent to 1.675 billion barrels of oil

• US oil consumption is currently 7.3 billion barrels oil/year

• Nearly one quarter of our oil consumption could be eliminated by full utilization of unused woody biomass

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Pennsylvania’s Forests – 16 million acres of biological “solar

panels” storing carbon energy!

•658 million tons (55%) of our forest is in “low-use wood” (LUW); 469 million tons are

potentially available for harvest

•This volume of forest wood could yield about 6 million dry tons per year in perpetuity

300 Million 40 lb bags of

wood pellets

3 million homes

6 Million Dry Tons Per Year is

Equivalent to:

5 - 10 Wood Ethanol

Plants

480-600 million gals

ethanol

600 District Energy

Projects

475 - 500 million gallons of #2

heating oil (Karakash, 2007)

How LCA works

http://www.epa.gov/climatechange/wycd/waste/lifecycle.html

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http://www.worldchanging.com/archives/009334.html

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Questions remain:

• When is biomass energy a smart

environmental option?

• Are “environmentally correct” and

“economically correct” mutually exclusive?

• Is LCA a way to produce scientifically sound

public energy policy?

• Will LCA evolve into a world standard policy

tool?

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