0:00Recording 61.

0:02You will hear two students discussing their assignments.

0:06First you have some time to look at questions 21 to 26.

0:10Hi Mike, how's it going?

0:42Actually, I was up last night with an assignment, so yeah, I'm tired,

0:47but I guess we'd better sort this presentation out.

0:51Well, we've done enough background reading,

0:54but I think we need to organise exactly what we're going to say

0:58about biofuels during the presentation and the order.

1:03I thought we could start by asking our audience

1:06what car engines were first designed to run on,

1:10fossil fuels or biofuels.

1:13Nice idea.

1:14Yes, when most people think about cars and fuel,

1:18they think about all the carbon dioxide that's produced,

1:22but they don't realise that that wasn't always the case.

1:26You're probably right.

1:28The earliest car engines ran on fuel made from corn and peanut oil,

1:33didn't they?

1:34Yes.

1:35The manufacturers used the corn and peanut oil

1:38and turned them into a kind of very pure alcohol.

1:42You mean ethanol?

1:44Yes.

1:45In fact, most biofuels are still based on ethanol.

1:49Actually, I've got some notes here about the process

1:53of turning plant matter into ethanol,

1:56the chemical reactions and the fermentation stages.

2:00It's interesting.

2:02The other students would appreciate it,

2:05but different biofuels use different processes

2:09and if we give a general description,

2:12there's a risk we'll get it wrong

2:14and then the tutor might mark us down.

2:17I'd rather we focus on the environmental issues.

2:21Fair enough.

2:22So the main plants that are used for biofuel production now

2:28are sugarcane, corn and canola.

2:33Of all of them, canola is probably the least harmful

2:37because machines that use it don't produce as much carbon monoxide.

2:43Sugarcane seems to be controversial.

2:46It doesn't require as much fertilizer as corn does to grow,

2:52but when they burn the sugarcane fields,

2:55that releases loads of greenhouse gases.

2:58Yes, but some critics have suggested

3:01that the production of corn ethanol

3:03uses up more fossil fuel energy

3:06than the biofuel energy it eventually produces.

3:10For that reason, I'd say it was more harmful to the environment.

3:13I see what you mean.

3:15You're probably right.

3:17It's interesting how everyone saw the biofuel industry

3:21as the answer to our energy problems,

3:24but in some ways biofuels have created new problems.

3:28Well, in the USA,

3:30I wouldn't say that farmers are having problems.

3:33The biofuel industry for them has turned out to be really profitable.

3:38I think, though, that even in the USA,

3:41ethanol is still only used as an additive to gasoline or petrol.

3:46The problem is that it still has to be transported by trucks or rail

3:52because they haven't built any pipelines to move it.

3:56Once they do, it'll be cheaper,

3:58and the industry might move forward.

4:01That'll have to happen one day.

4:03At least the government are in favour of biofuel development.

4:07Yes, but Brazil's probably in the lead as far as biofuels are concerned.

4:14They've got to the point where they don't need to import any oil now.

4:20Which is great,

4:22and the industry in Brazil employs a huge number of people,

4:26but is it sustainable?

4:29I mean, as the population grows

4:32and there are more vehicles on the roads

4:35and there's more machinery,

4:37surely they can't depend so much on sugarcane?

4:41At some point, there has to be a limit

4:43on how much land can be used for sugarcane production.

4:47Certainly, if you want to preserve natural habitats

4:50and native wildlife.

4:52I think that whatever problems Brazil's facing now,

4:56the same will be true for any country.

4:59You have to weigh up the pros and cons.

5:02Well, we probably won't see an increase in biofuel use.

5:07I mean, they won't replace fossil fuels

5:10until we can find ways to produce them cheaply and quickly

5:15and with less cost to the environment.

5:17Making sure they require minimal energy to produce.

5:21Exactly.

5:22And in a way, that means they have to cost less than fossil fuels.

5:27Certainly when you're filling up your car.

5:30Yes, and whatever other kind of engines

5:33use fossil fuels at the moment.

6:05Now listen and answer questions 27 to 30.

6:10Alright, so in the last section of the presentation,

6:14what problems are we focusing on?

6:17Well, we've already had a look at different types of pollution

6:21in the first section,

6:23so we can leave that out.

6:25But the biggest issue related to biofuels

6:28is that land is now being used to grow biofuel crops

6:33and that's contributing to global hunger.

6:36Indeed.

6:38It doesn't seem right we're using corn to run cars

6:42when people can't afford to buy it to eat.

6:46Yes, let's talk about that.

6:49The other thing is that in some countries,

6:52the way that biofuel crops are grown and harvested

6:56still produces a great deal of pollution,

6:59really damaging to the atmosphere.

7:02Okay, that's definitely an issue we should look at.

7:06Let's not finish on a negative note though.

7:09Why don't we talk about the potential new sources of biofuel?

7:14So rather than corn and sugarcane,

7:17what other plants could be used?

7:20Good. Some companies are exploring the possibility of using wood

7:25and seeing how that can be used to make ethanol.

7:29Yes, and algae is another possibility.

7:32You can grow it in any water and it absorbs pollutants too.

7:36I read that.

7:38And grasses, they're another plant

7:41that researchers are investigating as a biofuel.

7:44And these kind of plants aren't used as food.

7:48That is the end of section 3.

7:54You now have half a minute to check your answers.

7:57Now turn to section 4.