TOEFL integrated writing: fuel-cell engines

In the lecture, the professor made several points about powering engine using hydrogen, the professor argues that hydrogen could never replace fuel. The talk by the professor however, is different from the reading. According to the reading, hydrogen is a good replacement of fuel that will help producing electricity. But the professor casts doubts on that view with several points.

The first point is the availability. The reading states that hydrogen is widely available and it's easy to exploit. The professor' point is different from the reading. The lecture says that despite the fact that hydrogen is present in all the common elements on earth, producing pure liquid hydrogen is extremely difficult and requires very sophisticated procedures that consume a lot of energy.

Another point made by the professor is that using hydrogen can't reduce pollution. This is not what the reading says. The reading says that replacing fuel with a clean energy is a key factor to reduce pollution. However, the professor says that hydrogen purification requires a lot of energy: fuel for instance which harms the environment.

Finally, the professor doesn't think that hydrogen is profitable. In fact, Producing hydrogen is very expensive and requires some rare materials such as Platinum.

In conclusion, the professor challenges the claims made in the reading by showing that hydrogen is not a good substitute of fuel.