Unit 1. Exercise 9b. Talk on a hydrogen-based economy

Speaker So welcome back. I hope you had a good lunch and are ready for an exciting new topic, because now I'd like to move onto the issue of the hydrogen economy. As I'm sure you know, some universities are undertaking R&D into finding a substitute for fossil fuel. Hydrogen seems to be the best candidate although at present production is quite expensive. The gas can be obtained from fossil fuels such as natural gas, but in this process CO₂ is released, which is not beneficial. Research is therefore focussed on producing hydrogen from water via electrolysis because the production of greenhouse gases can be avoided in this way. The only products are oxygen and hydrogen. One of the most interesting ways of doing this is to use photovoltaic cells. The current generated from these cells could be used for the purpose of electrolysis. If we move on now to the possible applications, hydrogen could be used in a number of ways instead of hydrocarbons. Aircraft engines could be modified to burn the fuel. Road vehicles could also burn hydrogen in internal combustion engines with certain technical changes. The big advantage, again, would be that the combustion process produces no greenhouse gases. Hydrogen could also be utilized to power vehicles with electric motors in conjunction with fuel cells. And, again in combination with fuel cells, hydrogen could be harnessed for electricity production in decentralized energy systems. Storage of the gas, however, is one of the biggest challenges. It can be stored in pressurized containers, but the problem is that the quantities needed for practical application are very large when compared with the fuels we use today. This is particularly true for vehicles and aircraft. Weight would also pose a problem. But perhaps the biggest obstacle for this technology is the reluctance of governments and oil companies to support research. So it would seem that whether the hydrogen economy ever becomes a reality will depend on the market.

Дата добавления: 2015-08-03