Solar energy conversion with hydrogen-producing cultures of the blue-green alga, Anabaena cylindrica

Conference · Sun Jan 01 00:00:00 EST 1978 · Biotechnol. Bioeng. Symp.; (United States)

OSTI ID:5746741

Hallenbeck, P C; Kochian, L V; Weissman, J C; Benemann, J R

It was demonstrated that a catalytic, sustained production of hydrogen from water can be carried out under outdoor conditions using a simple glass converter and a stationary blue-green algal culture. This process meets the basic technical requirements of biophotolysis. Improvement in rates of hydrogen production by this system could be achieved by selecting wild-type blue-green algae better suited to hydrogen production and genetically improving the organism for this task. Specific requirements for the algae are tolerance of expected temperature variations, maximum nitrogenase (or, preferably, reversible hydrogenase) activity, increases in vegetative cell photosynthesis through decreased phycocyanin degradation during nitrogen starvation, and increased filament strength. One of the most significant requirements is that the cells continue exhibiting high levels of hydrogen production even when not stirred or mixed. Thermophylic, mat-forming, blue-green algae might provide suitable strains. The actual culture vessels and hydrogen collectors should be arranged horizontally with a gas space, so the carrier gas need not be pushed through a liquid head. The key constraint on a biological solar energy converter is the very low capital and operational costs allowable. A simple calculation shows that, if 3% of incident energy in the Southwest United States were converted to hydrogen, only 0.25 x 10/sup 9/ joules/m/sup 2//yr (21.9 x 10/sup 3/ Btu/ft/sup 2//yr would be produced, worth about $0.60, assuming $2.40/10/sup 9/ joules (approx. =$2.50/MBtu). In conclusion, biophotolysis using heterocystous blue-green algae has been demonstrated. The practical application of this system is dependent upon the development of low-cost converters and effective algal strains. 8 figures, 2 tables.

• Research Organization: Univ. of California, Berkeley
• DOE Contract Number: E(04-3)-34-239
• OSTI ID: 5746741
• Journal Information: Biotechnol. Bioeng. Symp.; (United States), Vol. 8
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
08 HYDROGEN
59 BASIC BIOLOGICAL SCIENCES
ALGAE
BIOPHOTOLYSIS
HYDROGEN PRODUCTION
SOLAR ENERGY CONVERSION
COST
THERMOPHILIC CONDITIONS
WATER
BIOCONVERSION
CHEMICAL REACTIONS
CONVERSION
DECOMPOSITION
ENERGY CONVERSION
HYDROGEN COMPOUNDS
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
PLANTS
140505* - Solar Energy Conversion- Photochemical
Photobiological
& Thermochemical Conversion- (1980-)
080106 - Hydrogen- Production- Biosynthesis & Photochemical Processes
550700 - Microbiology
140500 - Solar Energy Conversion