TOEFL integrated writing: fuel-cell engines

The authorities tend to replace internal combustion engines with better options and one of the proposed options is hydrogen-fuel cell-engines.

As an advantage, contrary to petroleum, hydrogen seems to be more available and less expensive than gasoline or diesel fuel. However, according to lecture, hydrogen cell-engines consume pure hydrogen that is not readily available and the process of its production is a time-consuming and complicated one. Moreover, it should be stored in liquid form in very low temperature, more than 200 degrees below 0, which makes the whole process nearly impractical.

The second thing that is mentioned as an advantage for hydrogen fuel consumption is the assumption that it is a green power source which pollute ecosystem considerable less than fossil fuels. Unfortunately, it is not true because the purification and production of hydrogen fuel is dependent on the energy which is derived from fossil fuels like coal and oil. This means lots of carbon dioxide and other air pollutants.

And the last problem with hydrogen cell-engines is that they are very costly. Platinum that comprises a vital element of these engines is a highly expensive metal that yet cannot be replaced with any substituent.

In this way, hydrogen cell-fuel engines are not yet green or economically competitive in comparison to combustion engines.