Should We Use Wood for Energy?An Introduction

Brief History: Energy in the U.S.

Source: EIA, 2007

Brief History: Energy in the U.S.

Energy Consumption by Source (1635-2000)

INSERT GRAPH

Source : EIA, 2007

Nonrenewable Energy

• Finite resources – Cannot be replenished over a short

period of time

• Fossil fuels– Fossilized remains of plants and animals

found in top layers of Earth’s crust– Coal, petroleum, and natural gas– In 2006, 86% of energy consumed in U.S.

produced with fossil fuels (U.S. EIA, 2006)

• Uranium (nuclear energy)

Renewable Energy

• Not depleted or can be replenished over a short period of time– Solar– Wind– Biomass– Hydroelectric– Geothermal

Photos courtesy of NREL

Renewable Energy: Future Trends

Source: EIA, 2008 (www.eia.doe.gov/oiaf/aeo/production.html)

Brainstorm

• What are some of the potential advantages and disadvantages to using: – nonrenewable energy sources?– renewable energy sources?

• How many strategies can we use to improve the energy situation?

Biomass

• Biological material from plants or animals that is either living or was recently living (Environmental Literacy Council, 2008)

– Food crops (sugar, corn, wheat)

– Grassy and woody plants– Agricultural and forestry

residues– Municipal and industrial solid

wastes– Landfill gas

Photo courtesy of NREL

Woody Biomass

• Plant material from trees and shrubs: roots, bark, leaves, branches, limbs, trunks, and vines

• Some sources of woody biomass – Urban waste wood

• Yard trimmings• Storm damage• Land-clearing debris

– Forestry residues• Thinning for forest health and wildfire,

disease, insect pest risk reduction• Ecosystem restoration• Branches from harvesting

– Wood grown for energy• Short rotation woody crops

Questions to Explore

• What do you know about using wood for energy?

• What do you need to know in order to make informed decisions regarding using wood for energy in your community?

• What do you think are some of the major issues associated with using wood for energy?

Potential Advantages of Using Wood for Energy

• Local and renewable resource

• Creates local jobs

• Can help keep land in forests

• Useful way to process “waste wood”

• Thinning results in healthier forests

• Can produce lower levels of sulfur, nitrogen, and heavy metals such as mercury than coal

• Carbon-neutral energy source

The Carbon Cycle

Potential Disadvantages of Using Wood for Energy

• Cannot meet all energy demands

• Challenges of transportation and storage

• Reduction of highly valued forests– Products– Landscapes– Recreation– Wildlife habitat– Watershed protection

• Concerns about air emissions

• Impacts on soil fertility, water quality

• Concerns about long-term availability

Harnessing Energy from Wood

• Break down cellulose in wood to release energy

• Uses of energy from wood– Generate electricity– Heat buildings with water, steam,

or air– Produce steam for industrial

purposes– Transportation fuels

Wood Conversion Technologies

• Direct combustion• Gasification• Anaerobic digestion• Pyrolysis• Fermentation• Alcoholysis

Photos courtesy of NREL

Wood Conversion Products

• Biogas• Bio-oils• Biodiesel• Ethanol• Wood pellets

Photos courtesy of NREL

Biogas

Bio-oils

BIO-OILS

HEAT POWER FUELS

BoilerCo-firing

Diesel engineMicro-turbineStirling engine

Biodiesel

Biodiesel

Canola

Soybean

Peanuts

Tung Oil Tree

Chinese Tallow (Popcorn Tree)

Chlorella

Switch Grass

Wood Chips and Residue

Giant Miscanthus

Ethanol

Sugarcane

Sweet Sorghum

PINE

EUCALYPTUS

WOOD RESIDUE

SMALL DIAMETER STEMS

Pellets

THINNING RESIDUE

Wood Pellets in the Southeast

EUROPE

FLORIDA

GEORGIA

Wood Pellets in Europe• Finland

– World leader in bio-energy generation (30% of total primary energy consumption)

• Sweden– World largest producer, importer, and consumer of wood

pellets– Pellet production in Sweden increases 25 to 30% every year– From 270 municipalities that have district heating systems,

250 use biomass fuels, mostly wood pellets

Case Study: Co-firing with Wood and Switchgrass

• Gadsden Steam Plant in northeastern Alabama

• Run by Alabama Power, subsidiary of Southern Company

• Uses switchgrass from a local farmer and wood from forest thinning, wood processing, and harvest residues

Case Study: Innovative Fuel Sources Generate Success

Telogia Power facility near Tallahassee, Florida

Telogia Power, LLC

• In operation since 1988• Liberty County, Florida• Currently supplies electricity to Seminole Electric• 14 MW gross electricity production• Fuel—190,000 tons/year

Wood (yard waste, forest management debris, timber harvest residues)

Paper waste (diaper tailings, unfit currency, confidential documents)

Occasionally more unusual sources such as contaminated peanut butter

Important Questions

• What factors should be considered?• How can a community address all of

these factors?

Sustainability

• Sustainable decisions are those that consider current and future impacts on three components: environment, economy, and society

Is Using Wood for Energy Sustainable?

• Brainstorm current and future impacts of using wood for energy on the environment, economy, and society

Many Factors to ConsiderEnvironmentalHabitat changeAir qualityWater qualitySoil fertilitySustainable management

EconomicLocal jobsCost of electricityCost of facilitySupply of woodCost of wood

SocialPublic healthQuality of lifePublic involvementFair decisionsValuesSense of place

Technical Conversion process Co-firing Transportation options Storage

Systems Thinking and Critical Thinking

• Systems thinking– Consider the whole picture– Think about all the parts of the system and how

they interrelate

• Critical thinking– Analysis– Synthesis– Evaluation

"We can't solve problems by using the same kind of thinking we used when we created them.“ - Albert Einstein

Should our community use wood for energy?