Submitted By niassuh123
Harvesting solar energy as a source of power
Photosynthetic microorganisms, such as micro-algae and cyanobacteria are able to harness low-intensity solar energy and store it as latent chemical energy in the biomass. This energy can then be released via biochemical conversion. The structural and storage carbohydrates in biomass have low energy content and it is necessary to concentrate the energy content further for fuel application. Anaerobic microbial fermentation is an efficient and widely used method for such conversion process. Useful renewable fuels produced by microorganisms include hydrocarbon, ethanol, methane and hydrogen. Biofuel cells which can release energy in fuel chemicals to generate electrical energy at ambient temperature have been developed.
Photo-biological hydrogen production: Chloroplast of some photosynthetic microorganisms such as the green alga chlorella in the presence of suitable electron acceptors is capable of producing H2 and O2 through direct photolysis of water. In the system, the substrate (electron donor) is water, sunlight as the energy source is unlimited, and the product (hydrogen) can be stored and is non-polluting. Moreover, the process is renewable, because when the energy is consumed, the substrate (water) is regenerated.
Ultimately, the sun is the only large renewable source of energy.
• We have a lot, but it is diffuse and not in a form we can use of most things for which we need energy.
Useful energy is in electrons!
• So, the goal is get the electrons from renewable, but diffuse sources into energy forms easily used by society: e.g., electricity,
• Fast growing - doubling time 0.5-1 day
• Do not require arable land
• Growth year-round
• High areal production
• Homogeneous (all cells are the same)
• Water-efficient; can recycle minerals • Not lignocellulosic