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Forest, carbon, and air
quality impacts from
wood energy facilitieswood energy facilities
February 10, 2011
Mary S. Booth, PhD
Massachusetts Environmental Energy Alliance
BIOMASS EMITS MORE CO2 THAN FOSSIL FUELS
1. Wood inherently emits more carbon per Btu
– Natural gas: 117 lb CO2/MMBtu*
– Bituminous coal: 205 lb CO2/MMBtu**
– Wood: 213 lb CO2/MMBtu bone dry
2. Wood is often wet, dirty (degrades heating value)– at 45% mc, 237 lb CO2/MMBtu
3. Biomass boilers operate less efficiently than fossil fuel boilers3. Biomass boilers operate less efficiently than fossil fuel boilers
– Utility-scale biomass boiler: 24%
– Average efficiency US coal fleet: 33%
– Average gas plant: 43%***
In practice: per MWh, biomass emits about 150% the CO2 of coal, and 300 – 400% the CO2 of natural gas
*http://www.eia.doe.gov/oiaf/1605/coefficients.html
** http://www.eia.doe.gov/cneaf/coal/quarterly/co2_article/co2.html
*** http://www.npc.org/Study_Topic_Papers/4-DTG-ElectricEfficiency.pdf
2
DOESN’T FOREST CARBON GROW BACK?
CONSIDERATIONS:
1. Regrowth ties up the carbon that was
released
2. But forests are already sequestering carbon...
How to take that into account?
3
CARBON RECOVERY AFTER ONE YEAR’S CUTTING
7
Change in Stored Carbon: Biomass Stand Carbon minus BAU Stand Carbon
(Previous slide: the BAU stand carbon was 70 tons; the biomass stand
carbon was reduced to 50 tons; 50 minus 70 = -20)
MANOMET
CONCLUSIONS
“Increases in biomass
energy generation can lead
9
energy generation can lead
to higher GHG emissions,
even when sustainable
forestry is practiced”
Sustainability does not
equal carbon neutrality!
Woody biomass fuels in Vermont
Logging residues: carbon payback periods are 10 – 25
years, since decomposition also emits CO2.
� One half of residues generated annually (USFS data): ~261,000 tons
New trees, including “low-grade” trees: carbon payback
periods are long – not a “low-carbon” fuel:
� Biomass Energy Resource Center says there are 894,900 green tons of “net
available low-grade growth” available annually in VT, after firewood and other
uses taken into account
BERC Vermont Wood Fuel Supply Study, 2010
Update
Study results for annual net available low-grade growth (NALG) wood in Vermont
alone and Vermont plus the adjoining 10 counties in New Hampshire, Massachusetts,
and New York (rounded to the nearest 100 green ton).
Wood demand at proposed facilities in Vermont
exceeds supply
Summed residues and “net
available low-grade growth”
wood (green tons)
Proposed facility wood
demand
Existing facility wood
Supply: Residues and “NALG” wood:
1,156,087 tons/yr (optimistic!)
Wood demand at proposed facilities:
1,756,500 tons/yr
Demand from existing and proposed:
2,822,500 tons/yr
demand
LAIDLAW 70 MW PLANT IN BERLIN, NH: PETITIONS TO INTERVENE IN
POWER PURCHASE AGREEMENT FROM EXISTING BIOMASS POWER PLANTS
Would require ~900,000 green tons annually. Petitions for intervention in the PPA:
• Concord Steam Corp.
• Clean Power Development LLC
• Bridgewater Power Co.
• Pinetree Power Inc.
• Pinetree Power-Tamworth Inc.
• Springfield Power LLC
• Whitefield Power & Light
• Indeck Energy
“A petition from the latter six alleges fierce competition for the biomass fuel, saying their own plants have a substantial interest in its availability and pricing, and Laidlaw’s PPA would directly affect them.”
MAKES NO SENSE TO THINK WE CAN MEET
FUEL NEEDS WITH “WASTE” WOOD;
INDUSTRY AGREES
William Perritt, editor of RISI wood industry newsletter, speaking
of the recent expansion in facilities:
“Hungry for large volumes of wood, and frequently “Hungry for large volumes of wood, and frequently
armed with government subsidies, the nascent
operations have triggered wood price spikes and cross-
grade competition in the tightest markets. The oft-
repeated assumption that forests and sawmills are
littered with waste wood, just waiting for cheap home
is proving largely erroneous.”17
MA: “The Fitchburg Power Station is a 17 MW waste wood and landfill gas fired power facility. The facility
burns whole tree chips”
NH: “Tamworth Power Station is a 22.5 MW waste wood power facility … The facility uses wood from trees
unsuitable for lumber or pulp”
NH: “The Bethlehem Power Station burns low quality wood, which is continuously replenished through the natural
forest cycles. The facility uses approximately 675 tons (per day) of whole tree chips”
NH: Schiller Station: “Currently, PSNH’s Schiller Station in Portsmouth operates three 50 megawatt coal-fired steam
boilers built in the 1950s. PSNH will replace one of these coal boilers with a new fluidized-bed boiler. This state-of-
the-art boiler will burn whole-tree wood chips and other clean low-grade wood materials to generate
electricity.”
EXISTING PLANTS ARE USING WHOLE TREE CHIPS
electricity.”
VT: “The Ryegate Power Station burns 250,000 tons of whole tree chips per year”
VT: McNeil Station (Burlington Electric): “Seventy percent of the wood chips that fuel the McNeil Station are
called whole-tree chips and come from low quality trees and harvest residues. The trees, a majority of
which are on privately owned woodlands, are cut and chipped in the forest. Clearcutting of woodlands is
limited to areas that need to establish a new crop of trees. It may also be used in some
instances to improve wildlife habitat. In these cases, the size of the area cleared is limited to a maximum of 25 acres.
To run McNeil at full load, approximately 76 tons of whole-tree chips are consumed per
hour. That amounts to about 30 cords per hour (there are about 2.5 tons of chips per cord of green wood)”
18
1. “… we found the need to go to a raw material source other than
bark. What we went to was basically the whole tree, which we
chipped and introduced through the infeed of our system.”
• “When we get into a 100 percent whole tree run, we’re
consuming upwards of 50 to 60 tons an hour”
2. "We're not taking any waste residuals. We're only taking whole
PELLET PRODUCTION INCREASES FOREST CUTTING
2. "We're not taking any waste residuals. We're only taking whole
logs, and not using any bark.“
3. “The company will need 200,000 tons a year of whole logs to
operate the pellet mill at full capacity.”
Biomass Power City/Town State tons
Plainfield Renewable Energy Plainfield CT 512,656
NRG Energy Uncasville CT 539,638
Watertown Renewable Power Watertown CT 404,728
Russell Biomass Russell MA 674,547
Pioneer Renewable Energy Greenfield MA 634,074
Berkshire Generations Pittsfield MA 539,638
Palmer Renewable Energy Springfield MA 512,656
CCI Energy Fitchburg MA 67,455
Laidlaw Berlin Berlin NH 876,911
Concord Steam Concord NH 202,364
Clean Power Development Winchester NH 269,819
Clean Power Development Berlin NH 337,274
Pellets City/Town State tons
Corinth Wood Pellets Corinth ME 280,000
International WoodFuels Burnham ME 200,000
Maine Woods Pellet Athens ME 200,000
Geneva Wood Fuels Strong ME 160,000
Greenova LLC Berlin NH 360,000
Lakes Region Pellets Barnstead NH 176,000
New England Wood Pellet Jaffrey NH 50,000
Woodstone Pellets Moreau NY 280,000
New England Wood Pellet Deposit NY 200,000
Curran Renewable Energy Massena NY 200,000
New England Wood Pellet Schuyler NY 200,000
Essex Box & Pallet Chesterfield NY 140,000
PROPOSED BIOMASS POWER AND PELLET FACILITIES, NEW
ENGLAND AND NEW YORK
Clean Power Development Berlin NH 337,274
Laidlaw Energy Henniker NH 269,819
Indeck Energy Alexandria NH 215,855
Catalyst Renewables Geddes NY 539,638
Alliance Energy Renewables Ogdensburg NY 337,274
Newton Falls Fine Paper Newton Falls NY 134,909
U.S. Salt Watkins Glen NY 200,000
NRG Energy Dunkirk NY 202,364
Griffiss Utility Services Rome NY 129,513
Beaver Wood Energy Fair Haven VT 391,237
Beaver Wood Energy Pownal VT 391,237
Winstanley Enterprises North Springfield VT 337,274
Access Ludlow Clean Energy Ludlow VT 337,274
Essex Box & Pallet Chesterfield NY 140,000
Vermont Pellet Works Lyndonville VT 150,000
Renewable Energy Company Island Pond VT 100,000
Vermont Wood Pellet Co. Clarendon VT 20,000
Beaver Wood Energy Fair Haven VT 220,000
Woodstone Pellets (Greenova) Berlin NH 200,000
Vermont Biomass Energy Island Pond VT 200,000
Total new wood demand:
12.4 million green tons annually
Existing biomass fuel use:
~8 million green tons annually
Total roundwood harvest, 2006:
22,077,140 green tons
NEW YORK STATE CLIMATE ACTION PLAN: EXISTING
GENERATION AND 2030 GENERATION FROM BIOMASS UNDER
9,000 GWH SCENARIO
6,000,000
7,000,000
8,000,000
9,000,000
10,000,000
MWh from Wood and Wood-derived fuels
22
0
1,000,000
2,000,000
3,000,000
4,000,000
5,000,000
1980 1990 2000 2010 2020 2030 2040
(Data 1990 – 2009 from Energy Information Administration)
MAINE: A CASE STUDY IN WHAT NOT TO DO
Power sector in 2007:
• 24% from biomass
• 23% from hydropower
• 41% from natural gas• 41% from natural gas
⇒ Low emissions (on paper): 5.57 million tons CO2
Real (but unreported) emissions from biomass:
• 7.9 million tons CO2
May 12, 1998
October 31, 2007
25-ACRE CLEARCUT, MAINE
~ 950 dry tons biomass
Enough fuel to power a 50-MW
biomass plant for about 21 hours
25
Regrowth negligible
after almost ten years
60,000,000
70,000,000
80,000,000
90,000,000
100,000,000
(gre
en
to
ns)
Wood pellets
Biopower and biofuels
WOOD DEMAND IS GROWING RAPIDLY
-
10,000,000
20,000,000
30,000,000
40,000,000
50,000,000
2009 2010 2011 2012 2013 2014 2015 2016
Wo
od
de
ma
nd
(g
ree
n t
on
s
27
RGGI STATES: BIOMASS POWER GENERATION VERSUS CO2 EMISSIONS, 2008
(WOOD/BYPRODUCTS ONLY)
25,000,000
30,000,000
35,000,000
40,000,000
45,000,000
Power sector CO2 emissions
CO2 from wood /by-products (tons)
Reported power sector CO2 (tons)
100,000,000
120,000,000
140,000,000
160,000,000
Power generation
Wood/by-products (MWh)
Total generation (MWh)
29
-
5,000,000
10,000,000
15,000,000
20,000,000
CT DE MA MD ME NH NJ NY RI VT
0
20,000,000
40,000,000
60,000,000
80,000,000
CT DE MA MD ME NH NJ NY RI VT
2,550
2,750
2,950
Mil
lio
n t
on
s ca
rbo
n d
iox
ide
BIOGENIC EMISSIONS MAKE FEDERAL EMISSION REDUCTION GOALS
IMPOSSIBLE TO MEET
3% reduction
from 2006
1,750
1,950
2,150
2,350
2005 2010 2015 2020 2025 2030
Mil
lio
n t
on
s ca
rbo
n d
iox
ide
EIA projected emissions
EIA projected emissions plus
biomass emissions
EIA projected emissions plus
biomass emissions, without the
benefit of CCS
30
14% reduction
from 2006
ENVIRONMENTAL WORKING GROUP, “CLEARCUT DISASTER”
Replace coal with biomass?
Current generation from coal:
1,900,000
2,000,000
2,100,000
US Total Electric Power Industry, GWh from Coal
1,500,000
1,600,000
1,700,000
1,800,000
1,900,000
1985 1990 1995 2000 2005 2010
Potential for co-firing biomass at coal plants (MWh)
80,000,000
100,000,000
120,000,000
0
20,000,000
40,000,000
60,000,000
1985 1990 1995 2000 2005 2010
MWh from residues (100%)
Existing wood (MWh)
5% coal (MWh)
Particulate matter emissions from thermal biomass:
comparison to residential wood burning
emission factor
(g/kg) tons fuel fuel moisture
emissions
(tons)
Woodstove 18.5 10 0.2 0.15
Catalytic stove 6.2 10 0.2 0.05
Pellet stove 2 9 0.1 0.016
emission factor
(lb/mmbtu) tons fuel fuel moisture
emissions
(tons)
4 MMBtu/hr
(school boiler) 0.22 1,500 0.45 1.6
15 MMBtu/hr
(lumbermill) 0.25 14,000 0.45 16.6
Small thermal biomass: comparing
emissions to oil
PM rate PM tons NOx rate NOx tons CO rate CO tons VOC rate VOC tons SOx rate SOx tons
Oil burner 0.03 0.29 0.12 1.18 0.04 0.39 0.025 0.25 0.21 2.06
Wood burner 0.22 8.68 0.182 7.18 0.163 6.48 0.004 0.16 0.002 0.08
Air permit application for Wyalusing School District, PA:
New biomass burner with multiclone, and new oil burner
Wood/oil 7.33 29.93 1.52 6.08 4.08 16.62 0.16 0.64 0.01 0.04
PM: emissions from biomass higher than from oil
NOx: emissions from biomass higher
CO: emissions from biomass higherVOCs, SOx: emissions from oil higher
Emission rates at existing and proposed biomass plants
generally exceed those from coal (heat input basis, lb/mmbtu)
PM PM NOx NOx CO CO SOx SOxCoal Biomass Coal Biomass Coal Biomass Coal Biomass
0.01 0.02 0.07 0.07 0.10 0.10 0.10 0.02
0.01 0.02 0.07 0.12 0.10 0.19 0.14
0.02 0.03 0.07 0.13 0.10 0.19 0.25
Three best existing performers “BACT clearinghouse”(boilers >250 MMBtu).
0.02 0.03 0.07 0.13 0.10 0.19 0.25
Emissions rates from proposed biomass plants not much better:
PM NOX CO SOx
Gainesville RE, 116 MW, FL 0.015 0.07 0.08 0.029
Perryville RE, 32.5 MW, MO 0.03 0.11 0.11 0.08
Sierra Pacific, 23 MW, CA 0.02 0.13 0.35 0.005
ADAGE, 65 MW, WA 0.03 0.2 0.074 0.32
Killen Coal Plant, OH: Significant increases in organic
hazardous air pollutants when co-firing 5% biomass
Small differences in control efficiency
make a big difference to PM emissions
Control
uncontrolled
emissions
(lb/mmbtu)
btu/lb
wood tons wood
tons PM
(uncontrolled)
control
efficiency
PM rate
(lb/mmbtu)
tons PM
emitted
Multiclone 9.0 4575 26,000 1,071 80.0% 1.8 214 Multiclone 9.0 4575 26,000 1,071 80.0% 1.8 214
ESP 9.0 4575 400,000 16,470 99.0% 0.09 165
Baghouse 9.0 4575 400,000 16,470 99.7% 0.027 49
Baghouse 9.0 4575 400,000 16,470 99.9% 0.009 16
EPA’s proposed emission limits recognize that biomass emits
more than coal
PM limits:
Existing coal and existing biomass plants have the same limit: 0.02 lb/mmbtu
New biomass plants are allowed to emit 8x more PM than new coal plants (0.008 lb/mmbtu
vs. 0.001 lb/mmbtu)
EPA’s proposed emission limits for biomass vs. coal
Hydrochloric acid: new biomass plants allowed to emit more than coal
Mercury: coal emits more
Carbon monoxide: biomass always worse, by order of magnitude
Dioxins/furans: coal and biomass comparable