CRP to Ethanol

Mario BiondiniScott PryorWon Koo

Kris Ringwall

Brief Background• Nationally 14 million ha in CRP• 53% in Great Plains and central corn belt

with 1.4 million ha in ND.• Average biomass yield of 4.8 Mg.ha-1.yr-1

(range 2.4-8.4).• With “current technology” can potentially

generate 1,550 L.yr-1 of ethanol per ha.

• CRP grasslands consist of perennial plants that are adapted to the climate, require limited maintenance.

• Generate minimal production and transportation-related greenhouse gas fluxes (Robertson et al. 2000, Tilman et al. 2006, Biondini 2007).

Roberts et al. (2000)

Tilman et al. (2006)

Tilman et al. (2006)

Issues

• Preserve and even enhance the original objectives of the CRP program: “the restoration and permanence of prairie ecosystems,…the protection of their long term productivity,…and the enhancement of wildlife habitats”

• Conversion technology will have to be robust to handle a variable feedstock supply with minimal variation in processing parameters or ethanol yield.

• There needs to be a careful assessment of the long-term economic feasibility of producing cellulosic ethanol from CRP biomass, in particular transportation issues.

Objective 1

• Develop new restoration techniques and management strategies to optimize biomass production for ethanol while maintaining the CRP program objectives.

Current Status of Objective 1• With funding from NSF and USDA we

have conducted extensive research in morphology, physiology, and growth patters of 60 species common to the great plains Grasslands.

• (Johnson and Biondini 2000, Levang-Brilz and Biondini 2001)

• Constructed a 3D plant-soil interaction model (3DMIPS).

• It can only run in the parallel cluster super- computer at NDSU.

• Biondini (2001,2003)

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Plant Growth:ƒ(RGRmax

; Leaves N & P concentration; Soil Water; Air Temperature; Hs of Light; Senescence)

R:S Ratio: ƒ(Soil Nutrients)

Biomass Translocation:ƒ(AGB; BGB, R:S; Senescence

Translocation Ratio; Soil Temperature)

Nutrient Translocation:ƒ(AGB-N; BGB-N; Senescence;

Min and Max R:S Nutrient Ratio;Root Age)

Night Shoot Respiration:ƒ(Respiration Rate; Hs Light; Plant Growth)

Shoot Death:ƒ(Death Rate, Senescence; Trampling;LAI;

Air Temperature; Soil Water, Grazing)

Root Respiration:ƒ(Respiration Rate;

Soil Temperature)

Root Death:ƒ( Death Rate; Root Age; Soil Water)BGDBt

SDB

Litter

OM & OM-N

Mineral Nutrients

Biomass Transfer to Litter:ƒ(Wind; Rain; Trampling)

Litter Decomposition:ƒ(Decomposition Rate; N;

Lignin; Soil Water& Temperature)

Root Decomposition:ƒ(Decomposition Rate; N;

Lignin, Soil Temperature;Soil Water)

Litter Release of Nutrients:ƒ(Litter Decomposition;

Nutrient Content)

Root Release of Nutrients:ƒ(Root Decomposition;

Nutrient Contents)

OM Respiration:ƒ(Sand Fraction; Soil

Temperature & Water)

OM Nutrient Release:ƒ(OM Respiration; Litter &

Root Nutrient Release)

Root Age Structure:ƒ(Time; Biomass Translocation;

Root Mortality & Respiration)

• Implemented two large scale field experiments in grassland restoration to test various hypotheses regarding diversity, production, and stability.

• The experiments involved 50 seed- mixtures (1 to 20 species) and various N and P fertilization levels.

• 400 and 300 plots each.• Biondini (2007).

New Treatments

• Superimpose a split plot design with 3 treatments.– No Harvest: one third of each plot will

continue the current treatment.– Yearly Harvest: One third of each plot will be

entirely harvested every year.– Rotation Harvest: One third of each plot will

be entirely harvested every other year.

Objective 2

• Construct a user-oriented model for the planning and ecological assessments of CRP-ethanol projects across a variety of climatic and soils conditions.

• Take 3DMIPS and make it a 1D model that can run in a desktop.

Objective 3 (Scott Pryor)

• Determine which combination(s) of plant species will produce optimal fermentable sugar yields.

• The task will involve individual species and mixed feedstock biomass characterization, and evaluation of biomass pretreatment conditions for mixed species feedstocks.

Objective 3 (Won Koo)

• Determine the optimal feedstock transportation, handling, and storage methods to deliver a steady supply of biomass from subdivided CRP regions to a centrally located cellulosic ethanol processing plant.