Biomass Feasibility Project Final Report - Xcel Energy

Most promising categories. The bar graph below narrows our focus to the categories we have
identified as economically feasible for bio-power applications. The gap between technical and
economic limitations varies by feedstock type. Technical limitations account for most of the
difference between the total energy and bio-power potential energy of hays, straws and stalks.
For woody biomass, most of the difference between total energy content and bio-power
potential is due to economic limitations. For manures each limitation plays a roughly equal role.
500,000
450,000
Total
Total
400,000
Technical
350,000
300,000
Billion Btu
250,000
200,000
Technical
Economic
150,000
100,000
50,000
Economic
Total
Technical
Economic
0
Agricultural Residues Wood Manures
Figure III-13: Theoretical, Technical, and Economic Potential of
Crop Residues, Wood, and Manures
Comparing Costs of Biomass and Fossil Fuels
Hays, straws, and stalks and woody residues are the most abundant sources for biomass power
feedstocks, but currently tend to be more expensive than coal. Figure III-14 illustrates the cost
components of baled switchgrass, logging residues, and hybrid poplars in comparison to
delivered coal. It is important to note that, as with other products, the per unit price of coal may
decrease with higher volumes. Large scale coal-fired power plants (hundreds of MWs) operated
under long-term utility contracts may pay around $1.08/MMBtu while smaller facilities (hundreds
of kWs to tens of MWs) will pay higher amounts around $2.60/MMBtu (Lindquist, 2007). When
comparing fuels for smaller plants, a higher cost of coal estimate would be more appropriate.
This of course does not include any added environmental taxes that may be implemented at a
later date (something to consider with such long-term operation schedules). Much discussion
surrounds the idea of establishing carbon taxes to combat global warming. If such taxes were
instituted, the price of coal could increase dramatically.
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Identifying Effective Biomass Strategies:
Quantifying Minnesota’s Resources and Evaluating Future Opportunities