Algal Biofuels

with thanks to: Chris Reddy Director, Coastal Ocean Institute Woods Hole Oceanographic Institution and in collaboration with: Scott Lindell (MBL, WHOI)

Emily Peacock

History

Rudolph Diesel (1858-1913); died likely of suicide.

• He developed the idea of an engine using high plug. • Patent awarded in 1892.

History (continued)

• A diesel engine runs on straight peanut oil in 1900 at Paris Exposition oils (SVOs). biodiesel (

as we know it

)

(wins prize)

• Lots of failures using straight vegetable • It was recognized that it was best to modify fuels and not engines. Led to • Interest fluctuates with oil prices in US

Background

• One of the most promising fuel alternatives is fats. • Many tout its ability to enhance engine lubrication, decrease harmful emissions, and minimize the • It is formulated in a variety of mixtures from B2 fossil fuels) to B100 (100% biodiesel). • Almost any diesel engine can be run on B2 though B20.

Distributors of biodiesel in the US (www.biodiesel.org)

Fats from vegetable oil

Generally liquids at room temperature

18:1 glycerin fatty acids 18 18:2 Some use this in diesel engines; called straight vegetable oil (SVO)

Fats from animals

Solids at room temperature

18 18 18

What is biodiesel?

They are the fatty acid methyl esters (FAMEs) that result from the chemical breakdown of glycerides.

H 3 C O H 3 C O C 16 FAME

Biodiesel Production: 3 Step Trans-Esterification Reaction

☺

Comparison of Properties

Gas chromatography

inlet 60-m long column detector

Typical gas chromatogram

– components vary in some molecular property that

can be used by a GC stationary phase to separate them from one another

C 10 C 12 C 14 C 16 C 18 C 20 Time (min)

(n-alkanes)

Hill et al (2006) PNAS

• “Devoting all US soybean production would have an offset of 6% on diesel demand…… • “However, because of the fossil energy required to produce biodiesel, this change would provide a net energy gain to just 2.9% of US diesel consumption…..”

Algae-based bidiesel

– Grow algae and press or extract the oil from them.

– Algal oil can be transformed with simple chemical reactions to biodiesel.

– Many consider it the “biofuel of the future”

Algal Biodiesel

• No “food for fuel” issues.

• Harvest almost daily.

• By products: Glycerine (food and other industries); Protein (fish farms); etc • Lower emissions when burnt.

One study published in 2007 entitled, “Biodiesel from Microalgae” in Biotechnology Advances, indicated that algal-based biodiesel is the only biological source capable of replacing fossil-fuel diesel.

US Energy Department study says that if algal biofuels replaced petroleum in the US market, an area 15,000 square miles would suffice (like Maryland!)

Got algae?

Possible Biofuels “farm”

Photo Bioreactors

Raceway Pond Product

Algal Concentrate

chemical reaction algal oil (algal oil is too viscous to be used as a fuel alone and must be converted to biodiesel) biodiesel

Got algae?

Be careful with the hype

Take data from the “bench” and extrapolate to millions or even billions of gallons of water/algae. Problematic?

WHOI and MBL’s initial research • Involved in a proposal for a one-acre sized marine biodiesel production site in Cape Cod.

• Motivated to identify the best algae for this region.

• Began a survey of local species this past summer.

Solix plant, CO

What about the cost?

ex. Solix right now  $33/gallon paired w/ waste heat & CO2 selling by-products   $5.50/gallon $3.50/gallon (but) that’s still $150/barrel!!

goal is to get down to $1.50 gallon (or $60-80/barrel)

Algal biofuels benefits

• home-grown (less imported oil) • biological efficiency: algae create oils that can be harvested every 5-7 days • energy density (they are 10-60% oil) • no food-for-fuel problems (unlike ethanol) • could use waste CO 2 and heat from coal

Algal biofuels problems

• Will take years to optimize technology.

• Cost still high • Still dealing with hypothetical scaling.

• Biodiesel is likely short-lived. • Green diesel and other green fuels are the future on the commercial scale (same chemical structure as traditional fossil fuels).