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Dominik Kaestner M.S. Candidate University of Tennessee Department of Forestry, Wildlife and Fisheries February 19, 2014 12:20 pm 160 Plant Biotechnology Building

Wood Pellets A Sustainable

Energy Source ?

Ø  Introduction

Ø Current Knowledge

Ø Future Directions

Ø References

Outline    

1 1

(EDF, 2013)

Introduction – Global Warming  

2

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(Scripps, 2014) 3

Introduction – CO2  

379.88 ppm

January 19, 2014

Introduction  

(Le Quéré, 2009)

Introduction – CO2  

4

91% 33.4 billion metric tonnes

Fossil Fuels & Cement

9% 3.3 billion metric tonnes

Land Use Change 2010

26% 9.5 billion metric tonnes

24% 8.8 billion metric tonnes

50% 18.4 billion metric tonnes

Atmosphere

Land

Oceans

(EIA, 2011)

Introduction – Global Energy Consumption  

5

Qua

drill

ion

Btu

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Current Knowledge – Wood  

6

“More than two billion people depend on wood energy for cooking and/or heating, particularly in households in developing countries.”  

(FAO, 2013)

Wood – Benefits  

7

Ø Local

Ø Abundant

Ø Renewable

Ø Low Cost

Wood – Benefits  

8

O2

CO2

C  O2

CO2

O2 C  

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Wood – Issues  

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Ø High Moisture Content (40-60%) [k

Wh/

kg] 5  

0 60 Moisture Content [%]

Ø  Low Bulk Density

Ø  Irregular Shape

(BERC, 2007)

Wood Pellets  

10

“Wood pellets are a manufactured biomass fuel. They are made from wood waste materials that are condensed into pellets under heat and pressure. Natural plant lignin holds the pellets together without glues or additives”.

Biomass Fuel

Wood Waste

Without Additives

(Jones et al., 2009)

Wood & Wood Pellets – Benefits  

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Ø Local Ø Abundant Ø Renewable Ø Low Cost

Ø Efficient Transportable Ø Higher Energy Density Ø Long-term Storage (dry) Ø Convenient to Use Ø Low Ash Content

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(Cabin, 2013) (Alliance, 2009)

Wood Pellets – History  

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1970 2014

1973

 

Pellet stove invent. WA  

1983

 

Pellet stoves introduced U.S market  

2009

 

Tax credit for residential pellet stoves (30% -$1,500)  

2010

 First incentive prog. similar to European countries NH

2013

 

Southeastern U.S. become largest pellets Exporter 1.7 million tons

1993

 

Pellet Fuels Institute established

(Biomass, 2013)

PELLET MILL STATUS PLANTS CAPACITY [MILLION  

METRIC  TONS/YEAR]  

Operating 123 9,588

Construction 9 2,191

Proposed 14 3,955

Wood Pellets – Production in the U.S.  

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Total 146 15,734

(Jones et al., 2009)

Wood Pellets – Production  

14

Milling

Raw Material

Debarking/ Chipping Drying

Cooling

Packaging

Pelletizing App. 17% of the final energy content needed.

(Chen, 2009)

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(Andritz, 2012)

Wood Pellets – Production  

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1.  Die 2.  Rolls 3.  Feed Plow 4.  Knives

Pelletizing

(Andritz, 2012)

Future Directions – Torrefied Wood Pellets

16

Raw Material

Cooling

Bagging

Debarking/ Chipping Drying

Pelletizing

Milling

Torrefacation Conversion

(Hemicellulose)

No Oxygen

250- 300°C

(Ehrig et al., 2013)

Extremely diverging values and data “are often estimated by the torrefaction plant operators themselves”.

Future Directions – Torrefied Wood Pellets

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Energy density 4900 kWh/t 5400 kWh/t Bulk density 650 kg/m³ 705 kg/m³

Moisture content 6% <2%

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Take home message  

18

References  

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Aliance for Green Heat. 2009. Chronology of wood heat. <http://www.forgreenheat.org/ resources/history.html>. Biomass Magazine. 2013. Pellet Plants. <http://biomassmagazine.com/plants/listplants/pellet/US/Operational/page:1/sort:feedstock/direction:asc>. BERC Biomass Energy Resource Center. 2007. Guidebook Wood Pellet Heating. Massachusetts Division of Energy Resources. < http://www.mass.gov/eea/docs/doer/publications/doer-pellet-guidebook.pdf>. Cabin R. J., 2013. Wood Pellet Exports to Europe endanger vulnerable southern US wetlands. < wood-pellet-exports-to-europe-endanger-vulnerable-southern-us-wetlands>. Curran Renewable Energy. 2010. Energy From The Forest To You. Which is better … Hardwood or Softwood Pellets?. <http://www.curranpellets.com/documents/QualityPelletsMakeTheDifference.pdf> Environmental Defense Fund. 2013. 8 global warming effects that may surprise you. <http://www.edf.org/climate/8-global-warming-effects-may-surprise-you>. Ehrig, R., Gugler, H., Kristöfel, C., Pointner, C., Schmutzer-Roseneder, I., Feldmeier, S., Kolck, M., Rauch, P., Strasser, C., Schipfer, F., Kranzl, L., Wörgetter, M., 2013. Economic comparison of torrefaction-based and conventional pellet production-to-end-use chains. European Biomass Conference and Exhibition. Copenhagen. Eia U.S. Energy Information Administration. 2011. China and India account for half of global energy growth through 2035. <http://www.eia.gov/todayinenergy/detail.cfm?id=3130>. EcoNews. 2013. U.S. Becomes Largest Wood Pellet Exporter, Clearcutting forests and destroying wetlands. <http://ecowatch.com/2013/09/04/wood-pellet-exporter-clearcutting-forests-destroying-wetlands/>. EU. 2014. The EU climate and energy package. <http://ec.europa.eu/clima/policies/package/>. FAO. 2013. Wood Energy. <http://www.fao.org/forestry/energy/en/> Jones, D., Harper, D., Taylor, A., 2009. Wood Pellets – An introduction to their production and use. Univ. TN. <http://trace.tennessee.edu/cgi/viewcontent.cgi?article=1040&context=utk_agexfores>. Le Quéré, C., Raupach, M. R., Canadell, J. G., Marland G. 2009. Trends in the sources and sinks of carbon dioxide. Nat. Geo. Sci. 2, 831-836. MacLean, H., McKechnie, J., Zhang, Y. 2009. Life cycle assessment of wood pellet use in Ontario’s Nanticoke and Atikokan generating stations. <http://www.opg.com/power/thermal/MacLean%20Life%20Cycle%20Assessment%20of% 20Wood%20Pellet%20Use.pdf>. Scripps Institute of Oceanography. 2014. The Keeling Curve. <http://keelingcurve.ucsd.edu/>. Siyu Chen. 2009. Life Cycle Assessment of Wood Pellet. Master of Science Thesis. Univ. Göteborg. SW. Spelter, H. and Toth, D. 2009. North America’s wood pellet sector. U.S. Dep. of Agri., Forest Serv., Forest Prod. Lab.. Research Paper FPL–RP–656. Retrieved Nov. 1st 2012.

Picture Source  

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www.new-fuel.co.uk/why-use-wood-fuel.html www.forestenergysystems.com www.edf.org/climate/8-global-warming-effects-may-surprise-you http://keelingcurve.ucsd.edu/ www.altenergystocks.com picsmix.biz http://co2now.org/ www.landreport.com www.goodwp.com www.eia.gov/todayinenergy/detail.cfm?id=3130 www.behance.net/gallery/Wood-Is-Good/788133 www.e-energymarket.com www.biomassenergy.gr www.zzwbw.com www.scierie-gunstett.fr www.letsrecycle.com www.theguardian.com www.nomadetrade.com www.treefellers.co.uk/Logs-firewood.html www.new-fuel.co.uk/why-use-wood-fuel.html www.joewalker-haulage.co.uk http://de.fotolia.com/ us.intelextrememasters.com www.davesgames.net/catalog-lumber-logs-hay-bales.htm www.pelletstoves.ie ww.dadant.com/catalog/product_info.php?products_id=49 www.forestenergysystems.com http://midamericafreight.org/2012/11/wood-pellets-in-high-demand-in-the-eu/ http://hqvectors.com www.avanquest.com www.spyteksecurity.com http://fotolia.com marquezcharter.org www.mccombs.utexas.edu www.niobraranews.net www.pelletmill.net www.pellet.org/images/stories/2012%20-20wpac%20presentations%20part%20b.pdf www.motherearthnews.com www.sierraclub.org www.wpclipart.com ian.umces.edu www.ihk-demografierechner-bayern.de

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Now or later dkaestne@utk.edu

Any Questions ?  

21

(Chen, 2009)

Wood Pellet – Softwood vs. Hardwood  

I

(Curran, 2010)

Wood Pellet – Softwood vs. Hardwood  

II

The compression (app. 40 lbs per cubic foot) equalizes the density of the wood pellets whether the fiber is softwood or hardwood.

A premium quality wood pellet will have less than 1% ash content.

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(BERC, 2007)

Wood Pellet – Equal Energy Content  

III

1 ton pellets 120 gallons of heating oil 16,000 ft³ of natural gas 4,775 kilowatt hours of electricity

(USDA, 2007)

Wood Pellet – Energy Content  

IV

EU Climate Action 20 – 20 – 20  

V

Ø  A 20% reduction in EU greenhouse gas emissions from 1990 levels

Ø  Raising the share of EU energy consumption produced from renewable resources to 20%

Ø  A 20% improvement in the EU's energy efficiency

(EU, 2014)

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Impacts on Environment  

VI

(Ehrig et al., 2013)

Conventional Pellets vs. Torrefied Pellets  

VII

Definition Btu One British thermal unit is equal to the amount of heat needed to raise the temperature of one pound of water by one degree Fahrenheit, or 251.997 calories.1

1The American Heritage® Science Dictionary Copyright © 2005 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.