High Energy Biofuels derived from Eucalyptus oil

Carsten Külheim

Research School of Biology; ANU

Biofuel comparison

NHOC (MJ/kg) source

Bioethanol 29.7 Sugar (corn/sugarcane/biomass)

Biodiesel 37.4 Veg and animal fat/biomass

Jet-A1 42.8 Fossil

JP-5 42.4 Fossil

JP-10 42.1 Fossil

Dimerized monoterpenes

• In 2010 Ben Harvey and colleagues found that dimerized pinenes have similar physical and chemical properties as jet fuel up to JP-10

Biofuel comparison

NHOC (MJ/kg) source

Bioethanol 29.7 Sugar (corn/sugarcane/biomass)

Biodiesel 37.4 Veg and animal fat/biomass

Jet-A1 42.8 Fossil

JP-5 42.4 Fossil

JP-10 42.1 Fossil

α-pinene dimer 42.1 Pine/Eucalypts

β-pinene dimer 42.1 Pine/Eucalypts

Similar results with other non-oxygenated monoterpenes

Fuel terpenes

So… Where can we find large amounts?

• Engineered bacteria, algae or yeast

• Eucalypt leaves are filled with monoterpenes

Drew James King , Roslyn M. Gleadow and Ian E. Woodrow

Eucalyptus oil variation

• Huge within species variation of Eucalyptus oil! 10 – 30 fold and >10% of leaf mass

• There are also thousands of chemical structures in Eucalyptus oil

Eucalyptus oil (% DM)

0 2 4 6 8

Indiv

iduals

Can we find eucalypts with fuel terpenes?

• Yes

– Due to natural variations in commercial species (E. grandis, E. polybractea)

– Undomesticated species dominated by fuel terpenes (E. eremophila, E. eremicola…)

• Can also be engineered

How would it work?

1,8-cineole

additive to biodiesel

biomass to biodiesel

How much do we need to grow?

• Current yield: 200 kg / ha.y

• Elite clones: 500 kg / ha.y

• Selective breeding / engineering: ???

• Currently 20 m ha Eucalyptus plantations

– As feedstock: 10% of global aviation

fuel consumption

Example E. grandis in RSA

• Growing ca. 1 m ha E. grandis

• Foliage burned after harvest

– α-pinene dominant (av 40%)

– Oil yield is 1.5% -> ca. 300 kg / ha

– Harvest cycle is 7 y

– 120,000 t of α-pinene / harvest

– 17,000 t / y

What do we do?

• Quantitative genetics

– Understand the genetic basis of oil yield

– Provide genetic markers for breeding

• Develop methods for large scale screening of fuel terpenes

Example E. polybractea

60,000 trees from 40 families480 from 40 families selected for GWAS / GS

Eucalyptus oil is made of cineole

• Most E. polybractea have ~80-90% cineole

• Some individuals have 15% cineole

– Dominant terpenes are fuel terpenes

• Need method to screen all 60,000 trees

– Near Infrared spectroscopy can inform on quantity of fuel terpene

Near Infrared Spectroscopy

• Either hand-held NIR

– Measure ~30 plants / h

– High accuracy

• Or drone mounted NIR

– Measure ~1,000 plants / h

– Lower accuracy

Thank you!

David Kainer