1. There is no debt if the carbon stock in the forest is not diminished
A Rational Explanation of Why Wood Pellets are Carbon Neutral in Combustion
There is no debt if the carbon stock in the forest is not diminished
Presented by William Strauss, PhD
President, FutureMetrics
Director, Maine Energy Systems
Chief Economist, Biomass Thermal Energy Council
March 31, 2016

2. FutureMetrics 8 Airport Road Bethel, ME 04217, USA
Consultants to the World’s Leading Companies in the Wood Pellet Sector
“Intelligent Analysis and Thought Leadership for the Pellet Sector”
8 Airport Road
Bethel, ME , USA

3. Selection of Current and Recent Clients of our Team
Intelligent Analysis and Thought Leadership for the Wood Pellet Sector.
Selection of Current and Recent Clients of our Team
Formerly GDF Suez

4. Why we care about carbon emissions

5. The same logic applies to pellets used in the heating markets.
This discussion will be in the context of using industrial wood pellets as a substitute for coal in pulverized coal power plants.
The same logic applies to pellets used in the heating markets.

6. Examples of Power Plants that Use Wood Pellets
Avedore power station in Denmark - unit one 215 MW
DONG Energy

7. Examples of Power Plants that Use Wood Pellets
Full conversion of two 645 MW lines and co-firing at 85% on the third line.
Drax Power in the UK; the largest coal power station in England Six 645 MW lines – Three on wood pellets.
The largest decarbonization project in the EU.

8. Sustainability is always the starting point!
Environmental, Economic, Ecological…
Wood pellet are substituted for coal to lower carbon emissions. It is the lowest cost strategy that leverages existing generating assets and provides significant benefits for carbon mitigation requirements.

9. One metric tonne of wood contains about 450 to 500 kilograms of carbon

10. Carbon Neutral in Combustion?
The fundamental criteria for carbon neutrality in combustion is that the stock of carbon in the atmosphere cannot be increased by the combustion of the fuel.
Here is how that works for industrial wood pellets:
The source of material for producing the pellets has to be a forest that is certified to be managed sustainably.
Sustainable management means that the forest cannot be allowed to shrink in size.
A forest that does not shrink in size also means that the stock of carbon held in the forest does not shrink.
For example, the raw materials for the pellet production plant are procured from tree plantations that produce new growth at a rate of 1,000,000 tons per year.
The daily harvest is about 1 million divided by 365 or about 2,740 tons per day.
Those tons are converted to roughly 1,400 tons per day of industrial pellets (about 500,000 tons per year).
Those pellets are co-fired in a pulverized coal power plant as low carbon fuel. The supply chain carbon still counts for pellets just as it does for coal; but the net is that pellets produce about 88% less carbon emissions than coal for the same MWh’s – more on this later.
The carbon released by the combustion of 1,400 tons of pellets is absorbed contemporaneously by the 2,740 tons of new growth that same day.
There is no net new carbon added to the atmosphere.

11. There is no “debt then dividend” as some would suggest.
There is no waiting for a tree to grow and replace the harvested tree.
Industrial working forests are dynamic continuous systems. As long as the constraint that removal cannot exceed growth is met, the carbon stock is not diminished and every ton of carbon released by combustion is absorbed by new growth THE SAME DAY!

12. Continuously growing forests are what the lumber mills, pulp mills, pellet mills, and other users of wood products depend on.
They require a steady daily flow of wood that will be available essentially forever.
No one builds a pulp mill with the expectation that they will have a bunch of wood come in and then have to wait 35 years for the forest to regrow.
A properly sized mill (pellets, lumber, pulp, etc.) will have a daily input that does not degrade their ability to have that same daily input in perpetuity.
The net forest stock, and therefore the net carbon stock, is constant or growing.

13. A stylized view of how carbon is contemporaneously captured with properly managed forestry.

14. There is very little extra carbon benefit to an aging forest as the growth to mortality ratio reaches one.

15. on a contemporaneous basis.
In aggregate, the carbon released from combustion has to be equal to or less than the carbon sequestered
on a contemporaneous basis.
The vertical axis defines the yield per acre per year and that sets the limits of the annual harvest across the landscape.

16. Combustion of wood pellets derived from sustainable sources are carbon neutral in combustion.
The supply chain carbon footprint for wood pellets depends on fossil fuel used from harvest to delivery.
But the supply chain carbon footprint for any fuel that has to be mined, refined, and transported has to be considered as well.
Depending on supply logistics, wood pellets lower total CO2 emissions by 80% to 90% compared to coal in power plants.

17. From the EPA’s Science Advisory Board (SAB), Feb. 18, 2016
Page 1 - The EPA requested the SAB to peer review a revised science-based framework for accounting for biogenic carbon emissions, which the agency defines as “CO2 emissions related to the natural carbon cycle, as well as those resulting from the combustion, harvest, digestion, fermentation, decomposition, or processing of biologically based materials.”
Page 6 - A BAF [biogenic assessment factors] formulation based on changes in carbon stocks… is preferred over an emissions (flux-based) approach because it comports with conventional carbon accounting, has well-defined boundaries and follows conservation of mass as well as mass balance.
While our anticipated baseline approach is consistent with the EPA’s, BAF∑T would accumulate the annual differences in carbon stocks on the land, which accounts for the time path of net difference in CO2 emissions over time.

18. That is not a statement based on data!!!
That is not a statement based on data!

19. The so-called “fact” that the combustion of pellets releases more CO2 than coal is also false.
Coal started its life a very long time ago as biomass. And, it turns out, on a dry basis, coal and wood yield similar results in terms of the CO2 produced (in kilograms of CO2 per unit of potential energy) . Of course wood does not have zero moisture content (MC). But neither does coal.
The typical moisture contents by weight of coal are anthracite 3% - 16%, bituminous and sub-bituminous 8% - 20%, and lignite 39% or more.
It is the water in the solid fuel that causes its CO2 emissions to increase over the dry weight basis. The underlying process that drives this is “the enthalpy of vaporization”.
The correct solid wood fuel for comparison with coal is wood pellets not green wood chips.

20. Pellets are for Pulverized Coal Power Plants
Breakdown of US Coal Generating Stations
Why not wood chips and other “green” biomass?
They cannot be used in pulverized coal plants unless dried and milled first.
High transport costs per gigajoule due to high moisture content

21. Thank you William Strauss FutureMetrics
My home in western Maine on a fall day with a snow rainbow.
Most of the forest you see is managed working forest selectively harvested for supplying the forest products industries.