Fuel Cell

About two years ago, Daimler Chrysler amazed the world by introducing a car that emitted no smoke—only water came out of its exhaust. They called it Necar, short for New Electric Car, which could reach speeds of up to 90 miles per hour.

Fuel cells are currently a much-discussed topic. Especially in the field of automobiles, researchers are working tirelessly to make their use more accessible, believing fuel cells will play a vital role. In our current civilization, our need for fuel and energy is limitless. The more we advance in science and technology, the more dependent we become on electrical energy. Presently, we rely most heavily on petroleum-based fuels to produce electricity. Furthermore, for transportation, we have no alternative to petroleum fuel. The reserves of petroleum fuels we are using today will run out in the not-too-distant future. I say “not-too-distant” because no one can precisely predict when this will happen. That’s why scientists are continuously researching new sources of energy. Some well-known new sources include solar cells, tidal energy, wind energy, etc. These energy sources all work by converting the endless power of nature into electricity. But today, we will learn about a new method: the fuel cell. Fuel cells have attracted scientists’ attention as a new energy source.

How Fuel Cells Work:
In school chemistry classes, we learned about the following chemical reaction. It shows that hydrogen reacts with oxygen to produce water.
2 H2 + O2 = 2 H2O
The same basic reaction occurs in fuel cells. Fuel cells generate electricity through the electrochemical reaction between oxygen and hydrogen. In fuel cells, hydrogen is used as fuel. It subsequently releases its charge to generate electricity and finally combines with oxygen to form water. As by-products, only a very small amount of nitrogen oxide and sulfur dioxide are produced—so negligible that they can effectively be ignored. Thus, fuel cells have attracted the attention of environmentalists since they have almost no adverse effect on the environment. Moreover, their efficiency is around 80%, which is higher than that of many other types of power generation. For example, in thermal power generation, efficiency is about 40%. This means that only 40% of the petroleum fuel used in a thermal power plant is converted to electricity; the remaining 60% dissipates as heat or other forms of energy. In the case of fuel cells, the by-product is heat, which can later be used for heating water or in air coolers. Fuel cells can use natural gas, methane gas, or LPG as fuel. Hydrogen and oxygen are first extracted from natural gas, then converted to electricity through the fuel cell. The use of methanol as a fuel in fuel cells has opened a new chapter. The biggest advantage of methanol is that it remains in liquid form at normal temperatures and contains a much higher quantity of hydrogen. As a result, there is no need to carry heavy cylinders to store hydrogen fuel. Therefore, fuel cells are being used in buses and regular cars. Moreover, methanol can be produced in a very pure form (99.85%). The biggest advantage is that if used on a large scale, the cost of methanol would be much lower than conventional fuels.

Environmental Awareness:
There is intense discussion around the world about the greenhouse effect. Carbon dioxide is identified as the main culprit. The largest emission of carbon dioxide comes from vehicles burning fuel. Scientists estimate that using fuel cells in cars could reduce the greenhouse effect by up to 42%. Fuel cells do not negatively impact the environment since the only waste product is water. As a result, fuel cells can be used in environmentally sensitive places such as hospitals and residential areas. Fuel cells are often compared to batteries that contain a gas cylinder. Unlike other batteries, they do not need to be recharged—just refill the gas, and they’re ready to go. In practical use, fuel cells were first used by NASA (America’s space agency). They used fuel cells in the Apollo and Gemini missions as a source of electric power.

Fuel Cells in Bangladesh:
Bangladesh is currently facing severe environmental pollution. Dhaka is now considered the most polluted city in the world. The number of people wearing masks in Dhaka is rising day by day. If we can implement new technologies like fuel cells, we could at least partially manage our environmental pollution.