Abstract: This
 study presents a linear profit model with combined economic and 
environmental factors for a switchgrass-for-biofuels agricultural system
 in the southeastern U.S. The objectives are to establish 
conversion-to-switchgrass thresholds for various market prices and 
identify policy incentives that would ensure economic profit while also 
maximizing environmental benefits (carbon sequestration, displacement of
 fossil fuels) and minimizing negative impacts (global warming 
potential, nitrate loss). Weighting factors are chosen to represent 
incentives and penalties by assigning value to the impacts. With no 
other incentives, switchgrass market prices of at least $51 and $58/dton
 would be needed in order to make a profitable switch from 
corn/Conservation Reserve Program (CRP) lands and cotton, respectively. 
At a mid-range offering of $50/dton, feasible carbon credit prices of 
$3/ $8/ $23 per metric tonne CO2e would incentivize 
conversion from corn, CRP, or cotton, respectively. Similarly, a water 
quality penalty of $0.20/ $3/ $2 per kilogram NO3–N leached 
would incentivize the same conversions with resultant watershed 
improvement. At a lower price of $30/dton switchgrass, incentives based 
on valuation of ecosystem services begin to exceed feasible ranges of 
these valuations.
Highlights
►
 A linear effective profit model predicts conversion thresholds to 
switchgrass.
► Carbon and nitrogen fluxes can be valued and incorporated into producer choices.
► Farmgate prices alone of $51 and $58/dton switchgrass will entice conversion.
► Reasonable ecosystem service valuations will encourage adoption of switchgrass.
► Carbon and nitrogen fluxes can be valued and incorporated into producer choices.
► Farmgate prices alone of $51 and $58/dton switchgrass will entice conversion.
► Reasonable ecosystem service valuations will encourage adoption of switchgrass.
- Fig. 2. Potential profitability (net income) of switchgrass in comparison with cotton, corn and CRP land uses. Running three-year averages for traditional crops are shown,but annual corn and cotton profits are highly variable, [CV=2.1 (corn) and 1.0 (cotton), where CV=ratio of standard deviation to mean].
- Fig. 3. The effects of (a) carbon credit price and (b) nitrate penalty on expected improvements in net revenues from land use conversion. A greater slope of the line shows a greater sensitivity to increases in the weighting factors (x-axis). Switchgrass price is assumed to be at the recent contracted (mid-range) offering of $50/dton.
a School of Civil Engineering and Environmental Science, University of Oklahoma, OK 73019, USA 
b School of Natural Resources and Environment, University of Michigan, Ann Arbor, MI 48109, USA
Energy Policy via Elsevier Science Direct www.ScienceDirect.com 
Volume 48, September 2012, Pages 526–536
Keywords: Switchgrass; Ecosystem services; Carbon credit
 
  
  
 
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