The adverse environmental effects of using fossil fuels are fast becoming a pressing concern for all. The pollutants produced from burning fossil fuels has aggravated ecological threats such as global warming and depletion of ozone layer. That is why a search for an alternate and cleaner fuel source is on-going.
Many feel that hydrogen is the answer because burning hydrogen in air produces steam or H2O. However, production or extraction of hydrogen remains a challenge. That is why we need to explore different methods of extracting hydrogen from water. Hydrogen can also be produced by means of fossil fuels but, due to the above mentioned concerns, we would not focus on this method.
While around 95% of the total hydrogen production is done through hydrocarbons, the second most popular method for extracting hydrogen is through electrolysis of water which makes up around 4% of the total hydrogen production. Electrolysis basically splits water into hydrogen and oxygen gas through the application of an electric current. It has an efficiency of around 70-80% which is comparable to that of the hydrocarbons method which stands at 70-85%.
While the efficiency numbers indicate that it could be suitable for widespread industrial use, the main barrier for its adoption is the cost of production. The hydrocarbons produce hydrogen at a much cheaper rate while electrolysis suffers from higher costs due relatively high electricity rates.
In order to address the electricity costs issue, photoelectrolysis is being explored as an alternate way of performing electrolysis. It makes use of a device called a photoelectrolyzer which performs the electrolysis on water using solar energy as the source of electric current required for the process.
This process definitely has potential for an application on an industrial level. It is still relatively early days for the technology. There are concerns regarding the efficiency of the process and whether a solar based system could sustain the electricity demand for the hydrogen extraction process.
Photobiological method is another interesting approach of extracting hydrogen. It makes use of biological components, like bacteria and algae, which are used to produce hydrogen in a controlled environment. The process itself is in an initial research phase but the signs so far are encouraging. In this process, hydrogen gas is produced through a metabolic mechanism of algae. Scientists have found that if the algae is starved of sulfur in a vacuum then it makes use of an enzyme called hydrogenase which breaks down water into Hydrogen and Oxygen.
There is still little data regarding its efficiency so no comment can be made regarding its industrial application. It can potentially prove to be a near limitless source of clean hydrogen.
New Development: Enhanced Electrolysis
A new research has been recently conducted at the University of Glasgow which aims to refine the electrolysis process. They observed that if the electrodes are coated with molybdenum telluride catalyst and the current is applied in a specific pattern of pulses then hydrogen production can be increased by around 50% using the same amount of energy. This development can prove to be vital for making electrolysis an economical method of hydrogen production for various industries.