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Some implications of biomass power development in New York State

Some implications of biomass power development in New York State. Mary S. Booth Massachusetts Environmental Energy Alliance January 11, 2010. Biomass emits more CO2 than fossil fuels. Wood inherently emits more carbon per Btu Natural gas: 117 lb CO2/MMBtu*

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Some implications of biomass power development in New York State

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  1. Some implications of biomass power development in New York State Mary S. Booth Massachusetts Environmental Energy Alliance January 11, 2010

  2. Biomass emits more CO2 than fossil fuels • 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 • Wood is often wet, dirty (degrades heating value) • at 45% mc, 237 lb CO2/MMBtu • 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

  3. Manomet agrees: Biomass emits more CO2 than fossil fuels, even taking forest regrowth into account Manomet Biomass Study, Massachusetts Conclusions: Even taking forest regrowth into consideration, net biomass emissions for utility-scale biomass generation still exceed those from coal in 2050; carbon profile for small-scale CHP and thermal plants somewhat better, but still close to fossil fuels. Biomass power cannot be considered carbon neutral, “low carbon, or even close to “low carbon” if carbon additionality rules violated… and especially when trees are harvested to provide fuel. Sustainability does not equal carbon neutrality!

  4. Let it grow back? Correctly accounting for carbon emissions • Regrowth ties up the carbon that was released; • But forests are already sequestering carbon... How do we take that into account?

  5. Forest regrowth under BAU and biomass scenarios

  6. Carbon recovery after one year’s cutting 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)

  7. Carbon recovery after multiple years cutting: facility footprint

  8. MANOMET CONCLUSIONS “Increases in biomass energy generation can lead to higher GHG emissions, even when sustainable forestry is practiced”

  9. NY draft sustainability standard • Forest harvesting plan • USFS Forest Stewardship plan, harvest plan • Certificate of Approval under property tax law • Forest Stewardship Council, Sustainable Forestry Initiative, American Tree Farm certification • Maintenance of land for time period sufficient to resequester carbon/100 years … but “sustainability” not enough.

  10. Draft MA regs: biomass eligibility for renewable energy credits • Define “eligible biomass fuel” as “waste” wood, wood from land-clearing, forestry residues • Restricts forest wood removals to no more than 15% of commercial timber (equivalent to 50% of residues) • Minimal efficiency requirements (40%: too low) • Partial RECs granted for lower efficiency • Lifecycle emissions after 20 years no more than 50% of those from natural gas or boiler being replaced.

  11. New York Climate Action Plan:what role for biomass power? Technical Work Group scenario for Low-Carbon Portfolio Standard: 75% of electricity from low-carbon sources in 2030 • Goal: Addition of 9,000 GWh of “lower carbon sustainable wood and other biomass”

  12. Existing generation and projected 2030 generation under 9,000 GWh scenario (Data 1990 – 2009 from Energy Information Administration) In 2009: 536 GWh from wood and wood-derived fuels, 1.66 GWh from “other” biomass . Where will fuel for the increase come from?

  13. Woody biomass availability in NY Mill wastes largely spoken for • CHP, pellets, other uses (only 1.8% unused nationally) Logging residues: ~ 1.08 m dry tons/yr, total. • assume 50% available (extremely optimistic). C&D waste wood: ORNL NY estimate 1.9 m tons, NREL estimate 2.04 m tons total • overwhelmingly in urban areas – air pollution issues • given that “clean” wood is limited and has other uses, assume 50% total is available Total of ~ 2,200 GWhgeneration supportable with “waste” wood, with scrounging. New biomass plants will harvest trees that would not otherwise have been cut, leading to significant carbon emissions.

  14. 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 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.”

  15. Existing plants are using whole tree chips • 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.” •  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)”

  16. Current status NY biomass • Existing capacity, 2009: 97 MW from wood, 396 MW from “other biomass” • About 120 - 150 MW in the pipeline • Will require at least ~1.9 m green tons (~1.07 m dry tons) But biomass power plants are not the only new consumers of “energy wood”…

  17. Wood demand (green tons) of recently built and proposed “wood energy” facilities in NY Earlier slide: availability of “waste” from forestry and construction-demolition activities ~1.5 m dry tons, equivalent to ~2.7 m green tons. New demand already exceeds supply.

  18. Pellet production increases forest cutting • “… 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” • "We're not taking any waste residuals. We're only taking whole logs, and not using any bark.“ • “The company will need 200,000 tons a year of whole logsto operate the pellet mill at full capacity.”

  19. Proposed biomass power and pellet facilities, New England and New York 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

  20. Existing facilities are worried about competition for wood 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.”

  21. RGGI states: Biomass power generation versus CO2 emissions, 2008 (wood/byproducts only)

  22. Questions? mbooth@massenvironmentalenergy.org

  23. GHG emissions from “waste” wood • Construction and demolition waste • “methane myth” of decomposition overstated • Wood decomposition in landfills: Only 0 – 3% of the carbon from wood is ever emitted as landfill gas • “US landfills serve as a tremendous carbon sink, effectively preventing major quantities of carbon from being released back into the atmosphere.”* *Micales, J.A. and Skog, K.E. 1997. The decomposition of forest products in landfills. International Biodeterioration and Biodegradation 39:145-158.

  24. Landfilled wood products represent C sequestration Estimated carbon flux for forest and harvested wood products, from EPA’s Inventory of greenhouse gas emissions and sinks, 1990 – 2008

  25. OnandagaRenewables, Geddes NY • 507 mmbtu/40 MW • 562,000 tons of wood; “eligible sources of biomass include… woody material produced during commercial timber harvesting” Emissions 566,000 tons of CO2 – (permitting threshold is 75,000 tons)

  26. Let's say we have a 100-acre forest that has about 25 tons of green wood standing per acre, and that sequesters 0.5 tons of new carbon per acre, per year. So this means that this 100 acres is sequestering 50 tons of new carbon, per year. When you do carbon accounting for biomass: You have processes (fossil fuel burning, tree harvesting and burning) putting carbon into the air. You have trees taking carbon out of the air on the acres you don't harvest - the remaining 98 acres (in the first year). Trees take both fossil fuel carbon and biomass carbon out of the air. When you replace fossil fuels with biomass, you increase #1, because biomass emits more carbon per unit energy than even coal. Meanwhile, you are doing nothing to increase the rate of growth of #2 to compensate for the increase in carbon emissions. Under the biomass scenario, let's say 2 acres of the 100 are harvested every year for fuel. This means the first year you harvest and burn those two acres, you have liquidated 50 tons of standing carbon and put it into the atmosphere (2 acres at 25 tons of standing carbon per acre).   The 98 acres that you didn't cut were going to add 49 tons of new carbon (98 acres x 0.5 tons/acre) whether you harvested those first two acres, or not. This carbon sequestration would in turn take emissions from fossil fuels out of the air. The biomass scenariothus sequesters 49 tons of carbon (0.5 tons on each of the 98 unharvested acres), and emits 50 tons of carbon into the atmosphere from the two harvested acres used as fuel. Under a "regional" accounting system that allows carbon sequestration on unharvested lands to compensate for emissions from harvested lands, the net emission = -49 tons + 50 tons = 1 ton (carbon taken out of the air is expressed as a negative number). The no-biomass harvesting/fossil fuel scenario sequesters 50 tons of carbon (0.5 tons on each of the 100 acres left unharvested). Energy emissions from coal burning are 33 tons (the amount of carbon emitted by the amount of energy generation in the biomass scenario, down-adjusted to account for the lower carbon output of coal per unit energy). Net emission: -50 tons + 33 tons = -17 tons The difference between these two scenarios is thus 18 tons more carbon emitted under the biomass scenario.

  27. Maine: a case study in what not to do Power sector in 2007: • 24% from biomass • 23% from hydropower • 41% from natural gas • Low emissions (on paper): 5.57 million tons CO2 Real (but unreported) emissions from biomass: • 7.9 million tons CO2

  28. Other lifecycle emissions e.g., Transportation: Because the energy content of wood is lower: • Wood: ~4,258 Btu/lb • Coal: ~12,250 Btu/lb for bituminous/anthracite • Requires transporting ~3x more wood to get the same fuel value Manomet calculates about 2 gallons of diesel fuel required per ton of wood, for harvest and transport

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