Download - Texas pres oct_2008
Algae Energy - Challenges & Efforts
Narasimhan Santhanam, Oilgae
Presentation in Oct, 2008, Texas, USA
How difficult is it to achieve the energy Holy Grail?
Contents
• For each of the various aspects of algal energy
– Problems present
– Efforts & solutions
Aspects Considered• End products
• Strains
• Oil yields
• GMOs
• Methods to grow algae
• Choice of cultivation plant
• Problems in cultivation
• Open pond systems• Photobioreactors• Harvesting• Extraction• Transesterification• Energy input/output• Land requirements• Scaling up• Quality of biodiesel
End Products
• Biodiesel
• Ethanol
• Hydrogen
• Methane
• Biomass
Biodiesel
• Greenfuel - recycled CO2
• Solazyme - fermentation
• Blue Marble - polluted water systems
• Inventure - algae-jet-fuel
• Aquaflow - algae in sewage
• Aurora - GM algae
• Solix - CO2 from breweries
Biodiesel - continued
• Seambiotic - CO2 from powerplants
• Cellena
Ethanol
• Ethanol from GM cyanobacteria (Univ of Hawaii)
• Algodyne - algae PBR that can produce multiple end products (fuels), including ethanol
• Algenol - “algae produce ethanol in the gas form”
Hydrogen
• Using hydrogenase enzymes (triggered by sulphur deprivation) - biophotolysis
• Using Cu to block oxygen generation
• Manipulating genes that control the amount of chlorophyll
• DIY Algae Hydrogen Kit - Amy Franceschini & Jonathan Meuser - biophotolysis
Methane
• Methane production by pyrolysis (Wu et al, 1999) - direct pyrolysis of marine nanoplankton
Biomass
• “Under favourable conditions, some algae strains have produced over 180 T / ha /yr of biomass”
• Solena - Uses high temperatures to gasify algae.
Strains• NREL’s ASP did not specify any one species
as the best, though they concluded diatoms and green algae were promising
• Microalgae or macroalgae?• Blue Marble - wild algae blooms• Solazyme - Dunaliella species• C. reinhardtii - sulphur deprived to produce
hydrogen
Strains
• Others:– Neochloris oleoabundans
– Scenedesmus dimorphus
– Euglena gracilis
– Prymnesium parvum
– Phaedactylum carterae
– Tetraselmius chui
– Tetraselmius suecica
– Isochrysis galbana
– Nannochloropsis salina
– Botryococcus braunii
Oil Yield
• Increasing oil yield by:– Nutrient deprivation - Sulphur & Nitrogen
deprivation– Silicon depletion
• ACCase gene placed to increase fatty acid
GMO
• PetroAlgae - Environmentally-friendly algae
• Solazyme - Optimizing biochemical pathways for hydrocarbon production
Photosynthesis or Fermentation?
• Photosynthesis - many companies
• Fermentation - Solazyme
• FAO - “direct extraction of lipids appears to be a more efficient method for obtaining energy, than fermentation”
Choice of Plant
• Single or multi-purpose
• Multi-purpose– Combined with power plants– Combined with wastewater treatments and
sewage– Greenfuel - power plants– Aquaflow - sewage– Inventure - power plants?
Cultivation Problems
• Formulation of Medium– Calcium, Magnesium can cause precipitation
problems– Water might require conditioning– Montana Micronutrient Booster - GSPI
Cultivation Problems
• Provision of CO2– CO2 could cover a large part of operating costs– Covered area carbonators - bubble covers– In-pond carbonation sumps– Recycling of non-lipid carbon from extraction
residues
Cultivation Problems
• Water Circulation– Paddle wheels– Airlift pump– Archimedes screw pump– Gas lift mixing
Problems in Open Pond
• Light penetration– Circulate algae using paddle wheels– Placing the light in the system - submerged into
the tank– Passive optical system - Bionavitas
Problems in Open Pond
• Odour related problems– Result mainly owing to lack of oxygen– Planned cultivation and harvesting should take
care of this
Problems in Open Pond• Contamination, temperature, pH & salinity fluctations
– Owing to:• Temperature & light variances• Infiltration from local algae• Evaporation, dust particles, rain.
– Solution• Hybrid algae product system - cross between open and closed
pond systems - GSPI• Combo of open pond and PBR - Enhanced Biofuels &
Technologies
Photobioreactor Problems• Choice of PBR
– Dynamic Biogenics develops low-cost, scalable bioreactors
– Solix B iofuels - “Massively scalable PBRs”– Texas Clean Fuels - optimized for CO2
sequestration and biofuel feedstock production– Valcent - vertical bioreactor
Photobioreactor Problems• Choice of PBR
– Origin Oil - Helix bioreactor– Academic & Univ Centre in Nove Hrady -
Czech Republic - Penthouse PBR using solar concentrators with linear fresnel lenses
Photobioreactor Problems• Cost of PBR
– DEC Simgae system - simple, benefits of both & closed systems
Harvesting• Method of Harvesting
– Besides simple sedimentation, all other methods are expensive
• The “expensive” methods - straining, filtering, flocculation
– Cost-effective (?) methods• Induced bio-flocculation followed by sedimentation or
flotation• AlgoDyne Ethanol Energy - new process to harvest
biomass from marine algal blooms
Harvesting• Long harvesting period
– GreenFuel - harvests algae daily– Advanced Biofuel Technologies - Over-
expression of ACCase leads to overproduction of triglycerides
Harvesting• Long harvesting period
– GreenFuel - harvests algae daily– Advanced Biofuel Technologies - Over-
expression of ACCase leads to overproduction of triglycerides
Harvesting• Time of Harvesting
– Ability to determine the right time to extract oil from feedstock is critical
– Current methods to determine these are expensive, time consuming and unreliable
– BioGauge “bio-profiling” technology - from International Energy Inc.
Harvesting• Harvesting Cost
– Aquaflow - developed a scalable method for harvesting algae in the wild
Extraction• Choice of extraction
– Primary• Expeller• Solvent Extraction• Super critical fluid extraction
– Less well-known• Enzymatic extraction• Osmotic shock• Ultrasonic assisted extraction• Soxhlet extraction
Extraction• Cost of extraction
– Numbers quoted are quite high - what are the real numbers?
• Energy requirements– OriginOil’s new method to extract oil without
resorting to chemical solvents, using a process called lysing, built on their patented method of “Quantum Fracturing”
Transesterification• High FFA could create transesterification
problems– Basu & Norris (2005) have developed a process
to produce esters from feedstock that have a high FFA content using calcium and barium acetate as a catalyst.
– SRS Biodiesel - FSP-Series Acid Esterification pretreatment system for high-FFA feedstock
Energy Input & Output• Best-case - Macro-algae can generate 11000
MJ/dry algae & micro-algae 9500 MJ/T.
• Solena’s plasma gasification tech consumes less than 1/4 of the energy it produces
Land Requirements• Growing algae on solid carriers in ocean -
Kansas State Univ. - Jun 2008
• Nutrients for algae in sea water - algae grew much faster when supplied with dust from a desert
• Valcent’s Vertigro uses area above a plot of land.
• Algae grown in sewage ponds - Aquaflow Bionomic
Scaling Up• When transferred to outdoor test facility,
growth rate, % oil yield decreased dramatically from those from laboratory results (NREL) (biodiesel produced per acre in OTF was just 10% of that produced in lab)
Algae Biodiesel Quality• Not enough data• High FFA content• Solazyme tests algae biodiesel that has
superior performance under cold weather conditions (algae engineered to produce an oil with optimized fatty acid profile)
• One way of bridging quality gaps is to blend biodiesel from different feedstocks?
Conclusion
• We are still not yet there, but the clarity about the problems we face and the diversity of solutions being attempted make the goal look more reachable than ever before.
Thank You