I just read your article and I must be missing something. Burning wood chips is considered "neutral" because trees absorbed CO2 that is now being released - yet coal, or oil, is considered releasing new CO2. Aren't you really talking about time differences? Wood chips are releasing the carbon that was absorbed when they were alive in the past. Admittedly, that time may be fairly recent, but coal and oil absorbed carbon when they were formed billions of years ago. So why is more recent absorption of carbon being considered neutral and that absorbed billions of years ago is not?

I can see where co-burning can reduce a power plant's carbon emissions, but so is the energy output reduced. That is no different than we are discovering with ethanol, which has reduced mileage performance of automobiles.

This also doesn't address the issue of the low price of wood chips because they are a waste product. What happens when every utility wants wood chips - will be start cutting down forests to get more wood chips?

Sounds like an alchemy argument by environmentalists.

G. Allen Brooks
Houston, TX

Burning Biomass with Fossil Fuels is a great article. I am glad to see that attention is being paid to this new technology.

I am mainly responding to the carbon neutral statements in this article, "Biomass crops, such as trees, absorb CO2. When burned, however, the biomass material releases the CO2 back into the atmosphere. But, such discharges are considered "neutral," meaning that the plants absorbed the same amount as the materials released -- unlike traditional fossil fuels that essentially discharge all new CO2 into the air."

I agree with these statements completely. However, I think that it is important to acknowledge the fact that Biomass crops such as trees and switchgrass are considered carbon neutral at the very least. They are in fact carbon negative because of the carbon sequestration that takes place in their roots during the plants' lifetime of photosynthetic process. The underground plant mass that sequestered CO2 are left behind after harvest. Switchgrass, although not mentioned in the article, is a perennial grass and its carbon sequestration is greater than annual biomass crops since no plow methods are used and replanting is not required.

In my opinion the carbon negative system of biomass crops makes them an even more attractive option for offsetting greenhouse gas emissions and helping to make our country more independent of foreign oil.

Lindsay Crider
Auburn University
Graduate Student
Agronomy and Soils

I'm not sure I agree with your statement regarding "new CO2"

"Biomass crops, such as trees, absorb CO2. When burned, however, the biomass material releases the CO2 back into the atmosphere. But, such discharges are considered "neutral," meaning that the plants absorbed the same amount as the materials released -- unlike traditional fossil fuels that essentially discharge all new CO2 into the air."

Correct me if I am wrong but aren't fossil fuels made up of, for the most part, "fossil plants" hence their name. Therefore would not the CO2 being released from these "fossil plants" be as neutral as the CO2 being released from burning biomass? Or in the reverse wouldn't the CO2 being generated from the biomass be as "bad" as the CO2 released by the use of fossil fuels? Don't get me wrong; I am behind the use of renewables more than most people in our industry. But let's not sugar coat the use of them in generating electricity

F. Perry Odom
Electric Utility Forester
City of Tallahassee Electric

Further to your article on using biomass with fossil fuels, it is correct that some fossil fuel plants running on coal may be converted to add biomass to the fuel mix. Yet in order for the country to move to an overall higher biomass usage, new plant construction will be needed. I raise this issue because in the proposed Federal Energy Legislation, there are a couple of disconnects between biomass usage and current tax policy.

To wit, there is a distinction made between open and closed loop biomass in earning Production Tax Credits ("PTCs"). By far, the wood wastes generated in this country are not from specific energy crops (closed loop) but are a byproduct of timber harvesting and co- harvesting the non-commercial species. It may be a noble idea to grow energy crops, but in reality, the forests have been cultivated for years by the lumber and pulp and paper industries. Lumber and paper uses are the highest values for a tree farm. Or put another way, the resultant electricity price will be north of $100/MWHR if one want to draw on lumber trees for fuel. Yet using the limbs and tops by-product is a reasonable means to an electricity cost on par with a coal plant (especially after CO2/environmental costs).

Therefore, if one wants to achieve greater biomass usage, then the distinction between open and closed biomass should be dropped for PTCs.

A second disconnect is the in the co-firing area. Renewable Energy Credits ("RECs") follow the proportion of biomass versus fossil fuel usage when co-fired. The tax code is different. For PTCs, the use of fossil fuel co-firing is very limited, or the PTCs are not allowed (earned) at all. In terms of stimulating new plant construction, forcing the plant to essentially be a 100% biomass plant is counter- productive. Ultimately, the electricity consumer is paying for this electricity. There may be times over the 50-year life of a plant that biomass may become more expensive than fossil fuels or supplies are constrained. For example, heavy rains limit tree harvesting activity, and thereby, wood waste by-products. Heavy snows limit harvests as well. True a plant will carry an inventory, but do the PTC rules really need to be so rigid that on a particular hour, one can't use some fossil fuel to make up for a biomass shortfall? And in terms of electricity price, shouldn't a uti lity be able to use fuel price competition to ensure the electricity price to the consumer is reasonable? It may be a noble idea to ban any fossil use in these new plants, but ultimately the electricity user needs a reasonable electricity price, and the best means to achieve that is to allow some flexibility in the plant design so the operator has fuel price competition and alternative supplies (inventory) in his tool box. PTCs should adopt the same methodology as RECs and be attributable to the biomass usage. This change would be good public policy as it keeps the incentive, but does not force the plant design into an area where traditional utility cost management tools are lost.

I hope you will consider supporting the above changes to tax policy as the country debates the Federal Energy Legislation in Congress this fall. PTCs are a powerful tool to stimulate new investment in renewable energy. And by making the above noted changes, the goals of increased renewable energy investment can be achieved while maintaining utility cost management tools.

Mark S. Sajer
Managing Director
Summit Energy Partners, LLC

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