Life cycle greenhouse gas assessments of cellulosic ethanol concepts

Bioenergy Australia, Brisbane, 14 Nov. 2016

Jesper Hedal Kløverprisa, Nassera Ahmeda, Patrick McDonnellb, Sander Bruunc, Ingrid Kaag Thomsend, Uffe Jørgensend, and Niclas Scott Bentsenc

a Novozymes A/S, b BEE Holdings, c University of Copenhagen, d University of Aarhus

Content

1. Novozymes and state of the cellulosic ethanol industry

2. GHG assessments of cellulosic ethanol concepts

• Case 1: Hybrid biorefinery (sugar-based and cellulosic ethanol combined) • Case 2: Straw-based biorefinery

• Case 3: Miscanthus-based biorefinery

Brief overview of concepts and results

2

Novozymes: Biotech company

Note: Next largest enzyme players are DuPont (21%) and DSM (6%)

different industries

products (industrial enzymes and microbes)

Global presence

Bioenergy

of sales

3

Rethink tomorrow – Innovations across Bioenergy

Starch-based

ethanol (1G) Corn fiber (1.5G)

corn wheat sugar cane sugar beet cassava

Household waste and cellulosic sludge

yellow grease brown grease animal fats acid distillates sewage waste

wheat straw corn stover energy crops MSW

Cellulosic

ethanol (2G)

Biodiesel

Biogas

bagasse

woodchips

4

The 2G journey: 15 years of continuous development and one of our largest R&D investments

5

2001

Launch of

Cellic® CTec for

first demo plants

World’s first

commercial 2G

plant uses our

Cellic® enzymes

Pilot plants

worldwide testing

our enzymes

One of the largest

R&D investments

in our history

5 of 7 commercial

2G plants

worldwide use

Cellic® enzymes

Exclusive

partnership with

Brazil’s largest

ethanol producer

2005 2009 2012 2013 2015

Foundation Pilot stage Demo stage Initial commercial stage Optimization stage

15X Enzyme potency improvement

Lever of

value

creation

Phase 1 (2016-17)

Proof of technology

(1-8 plants)

Phase 2 (2017-2022)

Second wave

(8-20 plants)

Phase 3 (2020-…)

Growth

(20+ plants)

Phase 4

Maturation

• Several “first-of-its-kind”

advanced ethanol

technologies proven at

commercial scale (i.e.

capacity, stability and

conversion kinetics)

• Some of the current first

movers have the

potential to succeed

• Several “first-of-its-kind”

technologies successfully

replicated with competitive

economics across regions

• Advanced ethanol mandates will

be in place

• Strategic players are willing to use

their own balance sheets to build

further plants

• Large scale roll out of advanced

ethanol technology with financial

guarantees from technology

providers to make projects

bankable

• Project Financing available to the

advanced ethanol industry

• Best in class

efficiency

To

da

y

6

What do

you need

to believe?

Four phases of the commercial stage building on top of each other

• The continued ramp-up of the industry requires political support

• …which partly hinges on the promise of climate change mitigation

• This is a key ‘societal selling point’

• The topic is too important not to understand deeply

• Novozymes has

• in-house LCA capacity

• strong ties to academia

• deep insights in ethanol and enzyme production

• Quite unique position to explore the GHG profile of cellulosic ethanol and contribute to this research field

Life cycle GHG assessments of cellulosic ethanol concepts Why is Novozymes active in this research field?

Bioethanol Gasoline

Exploration

for best sites

Production

Refining

Transportation

fuel

7

Starting with the enzymes…

Lesson: GHG assessments of cellulosic ethanol must consider the development stage of cellulase production

GHG intensity of enzyme production: Reduced

Enzyme potency: Improved → lower dosages

Enzyme contribution to ethanol GHG emissions:

75% reduction in seven years

8

Enzyme contribution to carbon

footprint of cellulosic ethanol

Life cycle GHG analyses of cellulosic ethanol (case studies)

# Concepta Feedstock(s)

Authors Co-products Methods

(applied separately)

Status

1 ‘Hybrid’

biorefineryb

Molasses, sugar

crops, and

agricultural residues

J.H. Kløverprisg

N. Ahmedg

P. McDonnellh

Sugar-based and cellulosic

ethanol, power, fertilizers,

and animal feed

1) Consequential (ISO)d

2) Attributional (RSB)e

Critical ISO review

completed (panel of

three int’l experts)

2 Integrated

biorefineryc

Cereal straw J.H. Kløverprisg

S. Bruuni

I.K. Thomsenj

Cellulosic ethanol, power,

heat, upgraded biogas,

and fertilizers

1) Consequential (ISO)d Scientific paper in

progress

3 Integrated

biorefineryc

Miscanthus J.H. Kløverprisg

U. Jørgensenj

N.S. Bentseni

Cellulosic ethanol, power,

and fertilizers

1) Consequential (ISO)d

2) Attributional (EU RED)f

Results complete,

documentation in

progress

a All concepts are theoretical but considered realistic and feasible in a short term perspective (‘2020’) b Multi-feedstock concept combining conventional sugar-based ethanol, cellulosic ethanol production, and combined heat and power (CHP) c Cellulosic ethanol production combined with biogas production and CHP d System expansion applied for multi-output processes and marginal data applied to the extent possible e Roundtable on Sustainable Biomaterials: GHG method based on economic allocation for multi-output processes and average data f EU Renewable Energy Directive: GHG method based on energy allocation (primarily) for multi-output processes and average data g Novozymes A/S, Denmark h BEE Holdings, Mexico i University of Copenhagen, Denmark j Aarhus University, Denmark

9

Juice

Filter mud

(fertilizer)

Solid/liquid

separation Concentrated stillage (fertilizer)

Solid/liquid

separation Vinasse (fertilizer)

Excess yeast

(animal feed)

Fermentation

Distillation Bioethanol

(sugar-based)

Enzymatic

hydrolysis

Fermentation

Distillation Bioethanol

(cellulosic)

Bagasse

Pretreatment

Trash

Crop residues

Molasses

Diffuser

Sugarcane and

sweet sorghum

Mechanical

processing

Juice

Combined heat

and power

Lignin

Heat and electricity

(for internal use + exports)

Boiler ash (fertilizer)

Crop residues

Case 1: The hybrid biorefinery

Regional setting

• Dry tropical climate

• Low land utilization and low cropping intensity

10

Case 1: Hybrid biorefinery with system expansion

Molasses

Crop residues Grain sorghum

production

Foreground system

Su

ga

r

Gra

in

so

rgh

um

Sugarcane

production*

Bioethanol

Heat and

bioelectricity

Vinasse,

concentrated

stillage, filter

mud, and

boiler ash

Transport sector

Sweet sorghum

production*

Sugar

production US feed market

Corn production

(and ILUC)

Corn

Soymeal

production

Soybean meal

Fertilizer

production

Auxiliary inputs

(enzymes, yeast, etc.)

Grazing on

adjacent land with

higher densities

* On land previously used for extensive grazing

Livestock

grazing

Molasses

Gasoline

production

Hybrid

biorefinery

Displaced process

Induced process

Unaffected process

Land

Land

Electric grid

Natural gas-

based electricity

production

Fertilization of

agricultural land

Fertilizer

production

Land

Induced flow

Unaffected flow

Displaced flow

Legend

Overview not exhaustive! 11

Case 1: GHG results for the hybrid biorefinery

Consequential approach (ISO) Marginal data and system expansiona

• Molasses 11.6 g CO2e/MJ

• Sugarcane 1.3 g CO2e/MJ

• Sweet Sorghum 8.2 g CO2e/MJ

• Crop residues 4.2 g CO2e/MJ

• Auxiliaries 4.0 g CO2e/MJ

Attributional approach (RSB) Average data and economic allocation

• Molasses 8.5 g CO2e/MJ

• Sugarcane 2.6 g CO2e/MJ

• Sweet sorghum 8.0 g CO2e/MJ

• Crop residues 4.5 g CO2e/MJ

• Auxiliaries 5.1 g CO2e/MJ

Feedstocks/biorefinery (A) 29.2 g CO2e/MJ

Electricity exports (B) -13.1 g CO2e/MJ

Other co-products (C) -3.9 g CO2e/MJ

Bioethanol (D) = (A + B + C) 12.2 g CO2e/MJ

Gasoline, marginal (Ecofys) (E) 115.0 g CO2e/MJ

GHG savings ((E – D) / E) 89%

Feedstocks/biorefinery 28.7 g CO2e/MJ

Electricity exports (8%b) -2.3 g CO2e/MJ

Other co-products (3%b) -0.9 g CO2e/MJ

Bioethanol (89%b) 25.5 g CO2e/MJ

Gasoline, average (RSB) 90.0 g CO2e/MJ

GHG savings 72%

(A)

b Economic allocation factor a Modifications compared to original, reviewed study: - Time perspective for LUC changed from 30 to 20 years - Enzyme product and dose updated (to customized Cellic)

12

• Same feedstocks, same ‘land footprint’

• More excess electricity from the stand-alone units due to combustion of cellulose

• …but higher total GHG savings with the hybrid biorefinery concept (due to more efficient conversion of biomass)

• Lesson: Don’t focus on CI per MJ alone. Overall GHG reduction (‘project level’) is more important.

Hybrid plant vs. stand-alone units

110 kt molasses

1,400 kt energy crops

2G

• Ethanol: 160 mill. l/y

• Electricity: 300 GWh/y

• CI: -7.9 g CO2e/MJa

• Total GHG savingsb:

400 kt CO2e/y

140 kt crop residues

1G

110 kt molasses

1,400 kt energy crops

Hybrid

• Ethanol: 230 mill. l/y

• Electricity: 160 GWh/y

• CI: 9.9 g CO2e/MJa

• Total GHG savingsb:

500 kt CO2e/y

140 kt crop residues

a Result from original, critically reviewed study: 30 y LUC perspective, Cellic CTec3 for enzymatic

hydrolysis (newer version available now), no consideration of reduction in N2O from residue removal

b Versus marginal gasoline at 115 g CO2e/MJ

Higher total

GHG savings

Better CI per MJ

More electricity

More ethanol

Case 2: Straw ethanol

** 71 kg CH4 per Mg dry biomass

Case 3: Miscanthus ethanol

* Dry matter

P and K fertilizers applied to compensate for nutrient removal

(no additional N due to Danish fertilizer regulations)

N and C flows modeled by the University of Copenhagen (Peltre et al. 2016)

Assumptions primarily based on internal Novozymes model Electricity assumption partly based on publically available info from Beta Renewables

Biogas production

Excess

electricity

Electricity

and steam

Ethanol

production

Miscanthus

Combined heat

and power (CHP)

0.29 l/kg biomass*

Biofertilizer

Not considered in

this case study

Ethanol

Vinasse

Electricity

0.51 kWh/kg biomass*

Might even be 0.76

Lignin

Biogas**

grown on existing cropland

(worst case scenario)

Integrated biorefinery

Biogas production

and upgrade

Excess

electricity

Electricity

and steam

Ethanol

production

Straw

Combined heat

and power (CHP)

0.30 l/kg straw*

Biofertilizer

Renewable

energy gas

58 l/kg straw*

Ethanol

Vinasse

Electricity

0.27 kWh/kg straw*

Lignin

50%

removal

rate

Integrated biorefinery

Back on

field

14

• Highest single emission: Soil carbon (ΔSOC)

• Negative correlation with N2O field emissions

• With a 100 year time perspective, reduced N2O emissions exceed increased CO2 from ΔSOC (when measured in CO2 equivalents)

• Lesson: GHG emissions from changes in SOC should be seen in combination with impacts on N2O field emissions

Case 2: GHG emissions from straw ethanol

• Avoided electricity assumed to come from renewables (mainly wind)

• Soil carbon (ΔSOC) given as CO2 emissions annualized over 20 years

Conservative results

15

Modeled by the Uni. of Copenhagen

Notes Average of three cereal straw scenarios (temp. climate, 50% removal) Cereal produced on sandy loam (JB6 in the DK classification system)

Straw-based ethanol: GHG implications of electricity and time

Notes Results represent an average of the straw scenarios considered (barley, wheat, and wheat with intercrop) ‘Avoided electricity’: Grid electricity displaced by excess (bio)electricity from the biorefinery ‘Other’ includes reduced N2O field emissions and the co-product credit for avoided natural gas 16

Lesson: The ‘darker’ the avoided electricity and the longer the (LUC) time perspective, the lower is the GHG emissions of cellulosic ethanol

GHG savings: 60-140%

Case 3: GHG emissions from Miscanthus ethanol

17

Notes Miscanthus assumed to be grown on former wheat fields ILUC estimate (23.4 g CO2e/MJ on average) based on Laborde (2011) Difference between spring and autumn harvest primarily due to yield and soil carbon

Same general picture as on previous graph - here with potential indirect land use change (ILUC) included

Average results with 20 year land use change perspective

Consequential/marginal

Gasoline Bioethanol

Attributional Attributional/average

Marginal

US shale

‘Hybrid’ ethanol: Sugar-based and cellulosic ethanol (region with low land utilization, no ILUC from local energy crops) Straw-based ethanol: Average of three straw scenarios (cereal produced on sandy loam in temperate climate, 50% removal rate) Miscanthus ethanol: Average of spring and autumn harvest (feedstock grown on prime cropland, ILUC included)

EU RED

Hybrid Straw Miscanthus

Avoided electricity based on:

Natural gas Coal Renewables Avg. grid (DK)

EU FQD

CARB RSB US EPA

Ecofys ERA

Hybrid Straw

18

19

Conclusions and Perspectives Methodological consistency

• Ensure apples-to-apples comparisons (average to average, marginal to marginal)

GHG savings

• Substantial GHG savings (55–160%) for the three cases, even with conservative assumptions

• Total GHG savings (‘project level’) more important than savings per MJ

Avoided grid electricity

• High impact on cellulosic ethanol GHG emissions

• Type of grid electricity replaced is regionally dependent

ΔSOC and N2O field emissions

• Interconnected and should not be viewed in isolation

Enzyme contribution to carbon footprint of cellulosic ethanol

• Not fixed but depending on ongoing development in cellulase potency and production

Future perspective

• The potential for ethanol from sustainably removed crop residues (<18%) by 2030 corresponds to 50% of global gasoline demand (BNEF 2012)