upstream biomass energy

Upstream Biomass Energy

Michael Weatherl

Background Shell is investigating several unproven

lignocellulosic biomass-derived fuel and energy technologies

These could provide sources of Hydrogen, liquid fuels, and other valuable chemicals

The logistical and economic aspects of the processes are not yet fully understood

Advantages of Biomass Energy Clean, renewable source of energy Does not release additional CO2 into the

atmosphere Utilizes waste material Creates local jobs and decreases

foreign imports Several areas of high biomass

availability near areas of high demand for the end product

Project Description Identify key parameters governing bio-energy

economics, especially in the USA, Canada, and Brazil

Quantification of costs for upstream biomass collection and handling

Review several biomass conversion processes to establish economic baselines for comparison

Document the energy balance of the process Develop a simple economic model to help

guide decision making

The Bio-Energy Process

Collection & Densification Handling/Storage Transportation Conversion Distribution of End-Product

‘upstream’

Feedstock Resources - USA

Corn Stover (non-food portion): 100+ million tons

Forest Thinnings: 40+ million tons Primary Mill Residues: 40+ million tons Urban Wood Wastes: 35+ million tons Other Agricultural Waste: 50+ million tons

Estimated Sustainable Annual Supply

U.S. Biomass Resource Map

Feedstock Resources - Canada

Wheat Straw: 20+ million tons Forest Residues: 90+ million tons Mill Residues: 10+ million tons

Estimated Sustainable Annual Supply

Canadian Forestry Biomass

Canadian Agricultural Biomass

Feedstock Resources - Brazil Bagasse: 60+ million tons annually Highly developed sugarcane-to-ethanol

program

Brazilian Agriculture

A Note on Feedstocks… These numbers are conservative, and

take into account the main parameters of sustainable collection

Less than 10% of all agricultural residue is used

Pre-collected residues (bagasse & mills) tend to be used for inefficient boiler firing, but are still very low cost

What if? ‘Efficient Energy Crops of the Future’

Technology will yield more and more appealing products as time progresses. Agriculture is no different.

ORNL estimates that ‘Dedicated Energy Crops’ could provide nearly 200 million tons of biomass in the U.S. annually.

Feedstock Productivity

Corn Stover: 1.5 Wheat Straw: 1.2 Forestry Waste: 5 Energy Crops: >10

Annual tons of Biomass per acre:


Collection & Densification Handling/Storage Transportation Conversion

Biomass Collection: Case Studies

Agricultural Residue: Harvest & Collection Costs ($/ton)

Approximate Farm-Gate Cost: $27/ton

Mowing Baling Stacking TotalSource 1: Rice Straw 6 14 7 27

Source 2: Wheat Straw 7 8 11 26Source 3: Corn Stover 10 12 5 27

Biomass Collection: Case Studies

Collect/Bundle Foreward/Load Chipping TotalSource 1 16 5 3 24Source 2 7 8 11 26Source 3 10 12 5 27

Forestry Waste: Collection Costs ($/ton)

Approximate Roadside Cost: $26/ton

Biomass Collection: Conclusions One-Pass harvest of both grain and

waste biomass would eliminate several steps.

Sustainable collection is important Agricultural Residue: $27/ton Forestry Residue: $26/ton For centrally located feedstocks,

purchase cost is $5-$15/ton (based on LHV, alternate uses)


Collection & Densification Storage/Handling Transportation Conversion

Biomass Storage Agricultural waste that is only harvested once

or twice annually requires storage Large bales stored field side and covered by a

tarp will resist damage. This costs about $5/ton.

Forestry waste is generated year-round, and does not require storage

Mill residues and bagasse are stored at the site where they are generated.

Biomass Handling Agricultural waste is transported to a

local pickup/storage point. Forestry waste is forwarded to the side of

the road to await transport Mill residues and bagasse are loaded

directly onto trucks and sent to the conversion center

Biomass Transport

Truck Train Barge Pipeline?

Main Options:

North American Rail System

Transport Cost: Agricultural WasteFixed Cost ($/ton) Variable Cost ($/ton-mile)

Source 1: Rice Straw Bales 5.5 0.09Source 2: Wheat Straw Bales 4.5 0.19

Assumed Trucking Cost 5 0.14Source 3: Freight by Rail 11 0.03

Agricultural Waste Transport

0

5

10

15

20

25

30

35

0 50 100 150 200Distance (miles)

Tra

nsp

ort

Co

st (

$) Trucking

Rail

Delivered Cost: Agricultural WasteDelivered Cost of Agricultural Feedstock

0

10

20

30

40

50

60

0 50 100 150 200

Distance

Co

st ($

/ton

)

Cost After Storage

Delivered Cost (Trucks)

Delivered Cost (Rail)

Transport Cost: Forestry WasteFixed Cost ($/ton) Variable Cost ($/ton-mile)

Truck Transport 4 0.2Barge Transport (if possible) 15 0.02

Delivered Cost: Forestry WasteDelivered Cost of Forestry Residue

0

10

20

30

40

50

60

70

0 50 100 150 200

Distance

Co

st (

$/to

n)

Flat Costs

Delivered Cost

Barge (w here available)

Pipeline Transport

Pipeline Transport? Short term: probably not Long term: more likely Allows for economies of scale and

integrated processes

Biomass Transport: Conclusions

Agricultural Waste: <$50/ton Forestry Waste: <$42/ton Centralized Feedstocks: <$30/ton

Delivered Price:

Conversion Technologies Combustion (gasification)

Fermentation (MixAlco)

Scale is everything!

Gasification into HydrogenPlant Scale (tons of bioimass/day) Cost of Hydrogen ($/GJ)

345 17.081150 15.391730 14.29

Gasification

0

2

4

6

8

10

12

14

16

18

0 500 1000 1500 2000Plant Scale (tons of biomass/day)

Co

st

of

Hy

dro

ge

n (

$/G

J)

Predicted Plant-GateHydrogen Selling PriceCurrent WholesaleHydrogen Price

MixAlco MixAlco is a fermentation process which

utilizes cellulosic feedstocks (non-food sources such as waste from agriculture and forests)

Yields chemicals that can be made into acids, alcohols, and hydrogen

Developed by Dr. Mark Holtzapple of Texas A&M University

Primary Alcohol Selling Price per Capacity, for different Feedstock costs

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 1000 2000 3000 4000 5000

Tons of Biomass per Day

Sel

lin

g P

rice

($/

gal

)

$11/ton

$22/ton

$33/ton

$44/ton

$55/ton

Today

MixAlco Costs

A healthy skepticism… 15% ROI may not be high enough for

such a high-risk investment Feedstock quantity and quality are

inconsistent These numbers are educated guesses

and may overlook some unseen costs

Energy Balance

Lignocellulosic-derived ethanol has a higher NEV (Net Energy Balance - an estimated 60,000 Btu) because of a less energy-intensive conversion process, when compared to traditional ethanol sources like corn

Hydrogen will have even higher NEV because it does not require a fuel-grade liquid

Conclusions: Centralized residues appear to be the

most viable option presently Forestry waste also appears feasible,

but not as cost-effective Agricultural waste appears to be the

least economical feedstock presently Transport costs have the greatest

impact on optimal scale Infrastructure is the only showstopper

Acknowledgements:I’d like to thank the members of Shell Gamechanger for giving me the opportunity to take part in this project and learn so much this summer.

Special thanks to Jerry Morris, Jack Hirsch, Scott Wellington, Brendan Murray, Ron Reinsfelder, Jingyu Cui, Rebecca Hubbard, Russ Conser, Don Maynard, Tim O’Gorman, Jochen Marwede, Lori Glassgold, Jair Guarda, Jaison Thomas, and the rest of the Gamechanger team.

It’s truly been a pleasure!

upstream biomass energy

Documents