Photobiological hydrogen as a renewable fuel

Vidya Jose

doi:10.33765/thate.11.2.4

Abstract

The huge global energy consumption has raised concerns over the depletion in readily available conventional energy resources. Besides, there are harmful atmospheric effects of fossil fuels and the qualms of future energy resources. The world hence is in dire need of new renewable energy sources that are cheap, non-polluting, environmentally friendly, and clean. This is the only way we can stop using fossil. Hydrogen is considered as an ideal fuel for the future because of its high energy content and its clean combustion to water. However, extensive technologies are required to introduce hydrogen as an alternative clean and cost-effective future fuel, which brings about the relevance of the exploitation of the microorganisms for large-scale renewable energy production. Reports of photobiological hydrogen production by oxygenic photosynthetic microbes, such as green algae and cyanobacteria and by anaerobic photosynthesis, are summarized in this paper, with a focus on the major obstacles that must be overcome by scientific and technical breakthroughs to make way for commercially feasible energy. The principle, progress, and prognosis of photobiological hydrogen as a renewable energy source are reviewed.

Highlights

Concerns about environmental pollution, looming climate change, and dwindling fossil fuels are compelling reasons to switch to renewable energy sources sufficiently large in scale to meet worldwide demand
Its breakdown generates no pollutants unlike ethanol whose large scale use is predicted to release large amounts of carcinogenic acetaldehyde with the generation of large amounts of smog
Organic compounds like acetic acids, lactic acids, and butyric acids are converted into H2 and CO2 by photosynthetic bacteria in the presence of sunlight in anaerobic conditions. During photofermentation both hydrogenase and nitrogenase enzymes are involved in H2 production [11]

Summary

INTRODUCTION

Concerns about environmental pollution, looming climate change, and dwindling fossil fuels are compelling reasons to switch to renewable energy sources sufficiently large in scale to meet worldwide demand. All presently studied alternative sources are largely carbon neutral since the carbon released by their combustion is derived, directly or indirectly, from recently fixed atmospheric CO2 [1]. Since it is the lightest carbon-neutral fuel rich in energy per unit mass and easy to store, hydrogen has. Biological production of hydrogen is a method for its renewable production It could be through direct capture of solar energy or utilization of energy-rich organic material for photosynthetic fixation of carbon. Microorganisms, such as green microalgae or cyanobacteria, use sunlight to split water into oxygen and hydrogen ions [2]. The algae and bacteria could be grown in water that cannot be used for drinking or agriculture and could potentially even use wastewater [4]

PRINCIPLE AND PROGRESS

CONCLUSION