TRANSCRIPTS
engine. What’s different is that in a hybrid, there is a combination petrol and electric engine. As well as a small petrol engine for cruising, we introduce a light electric motor with a bigger battery to give us the extra power for acceleration. And just like the electric car, the hybrid can store energy through the process of regenerative braking.
Now … oh dear, I was going to mention advantages and disadvantages of this technology, but … ah … I see that time is moving on. So instead, I’m going to …
Unit 7, Lesson 7.3, Exercise A ≤2.5 1 com'bustion 2 'generate 3 accele'ration 4 'biofuel 5 ca'pacity 6 'maximum 7 'engine 8 tech'nology 9 con'ventional
10 ef'ficiency 11 'greenhouse 12 e'lectric
Unit 7, Lesson 7.3, Exercise B ≤2.6
Part 5 I’m going to finish with some comments on the challenges of production – in other words, manufacturing.
Now, the fact of the matter is, it’s a highly complex task to make hybrid and electric cars more widespread. The reason for this is that the car industry has to consider a variety of different factors – not to mention the fact that some of these factors are key problems in the technology itself. Let’s take mileage: drivers want to make long trips, so the limited independent range of electric cars has to be resolved. Plus, there’s the fact that there is very little infrastructure for maintenance; that makes the cars unattractive to the public.
OK. Where was I? Oh yes … So, manufacturing challenges include not only product design, but planning of how the products, and the new production machinery, maintenance networks, etcetera, can be introduced in a staged way.
You’ve probably heard about Gantt charts? It was Henry Gantt who came up with a very simple idea to help with scheduling, to enable these sorts of changes to be implemented – the Gantt chart. Gantt charts help with organizing and planning changes. The advantage of Gantt charts is that they show what processes are happening at any one time. So, although it was in the early 1900s that Gantt invented his charts, they are still very much used today. This carefully staged development is important because hybrid and electric cars rely on new technologies which are untested in industry, and don’t enjoy public confidence.
To sum up, then, new engine technologies are relatively immature. Let me put it another way … alternatives to fossil fuels aren’t ready to be introduced into mainstream, mass-market manufacturing at a competitive price.
Oh, I almost forgot to mention your research topics. OK, well, what’s important for this whole area is research and development. So I’d like you to find out about the main areas of research at the moment for the development of these technologies.
Unit 7, Lesson 7.4, Exercise B ≤2.7
Extract 1 Now, as we know, power supply is one of the most important issues in the design of more environmentally friendly cars. I asked you to look at the case of fuel cells, which have become the focus of a lot of investment. Fuel cells function in a way we fully understand, and produce a large amount of energy efficiently. The market, we are told, is looking for a new, environmentally friendly, alternative to petrol. So, why are fuel cells not more commonly used commercially? Let’s have some ideas. Firstly, can someone explain how a fuel cell works, please?
Unit 7, Lesson 7.4, Exercises C and D ≤2.8
Extract 2 LEILA: A fuel cell is an electrochemical cell, but instead of having all the fuel contained within it, as a battery does, the fuel and oxidant pass through it.
EVIE: Can you expand on that, Leila?
LEILA: Sure. The cell has a positive and a negative electrode in an electrolyte. Ions flow between them as part of the chemical reaction.
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