Powered by Hydrogen
hydrogen fuel cell technology in India finally is coming of age. Bharat Heavy Electricals Limited (bhel), based in Hyderabad, has developed a pack of 50-kilowatt (kw) phosphoric acid fuel cell (pafc). Though a handful of companies, based in other countries, have manufactured the cell, this is the first time that a pafc has been developed in India. "With this, India joins the select group of countries like usa and Japan which are using this technology," says H Krishnan, senior deputy general manager at bhel . The pafc will be installed at the at the Sree Rayalseema Alkalies and Allied Chemicals Ltd.'s plant based in Kurnool, Andhra Pradesh, and the hydrogen supply for the battery will also be obtained from the plant.
Fuel cells are used for generating power, for domestic heating, for air conditioners or in vehicles. In the us , pafc s are already in use in defense installations, hospitals, nursing homes, hotels and some power plants. onsi Corporation, a us -based company, has installed 200-kw pafc plants at over 170 sites worldwide.
A fuel cell operates on hydrogen and oxygen, emitting only heat and water vapour. Hydrogen can be obtained from caustic soda or chlor alkali plants. A Vishwanathan, the deputy general manager (research and development) at bhel, says, the pafc can be used for stationary power production and it fares better than many other types of fuel cells. It operates at about 200 c and the heat that is produced can be put to use as well, for example, to heat water.
Just as in other fuel cells, in the pafc energy is converted from the electrochemical form in hydrogen into an electric current. "The difference between the pafc and other cells is of the electrolyte used and the temperature at which the cell operates," says Vishwanathan.
Fuel cells are generally classified on the basis of the type of electrolyte they use. The pafc uses phosphoric acid as its electrolyte. The molten carbonate fuel cell uses either sodium or potassium carbonate as its electrolyte. Similarly, solid oxide fuel cell uses solid oxides for electrolyte and the alkaline fuel cell use alkaline chemicals as electrolytes.
Each type of fuel cell operates at a specific temperature. pafc operates at 200 c . The lower the temperature at which the cell functions the less cumbersome its operations. Reduced funtional temperatures makes the cell more versatile. "The challenge is to provide fuel cell power at a cost that can compete with that supplied through the grid," says Vishwanathan.