[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.66,0:00:04.80,Default,,0000,0000,0000,,What is hydraulic fracturing – or fracking ?
Dialogue: 0,0:00:04.80,0:00:09.80,Default,,0000,0000,0000,,Since the industrial revolution our energy consumption has risen unceasingly.
Dialogue: 0,0:00:09.80,0:00:17.38,Default,,0000,0000,0000,,The majority of this energy consumption is supplied by fossil fuels like coal or natural gas.
Dialogue: 0,0:00:17.38,0:00:21.80,Default,,0000,0000,0000,,Recently there has been a lot of talk about a controversial method of extracting natural gas:
Dialogue: 0,0:00:21.80,0:00:25.80,Default,,0000,0000,0000,,Hydraulic fracturing or fracking.
Dialogue: 0,0:00:25.80,0:00:30.58,Default,,0000,0000,0000,,Put simply, fracking describes the recovery of natural gas from deep layers inside the earth.
Dialogue: 0,0:00:30.58,0:00:34.63,Default,,0000,0000,0000,,In this method, porous rock is fractured by the use of water, sand and chemicals
Dialogue: 0,0:00:34.63,0:00:39.50,Default,,0000,0000,0000,,in order to release the enclosed natural gas.
Dialogue: 0,0:00:39.50,0:00:42.78,Default,,0000,0000,0000,,The technique of fracking has been known since the 1940s.
Dialogue: 0,0:00:42.78,0:00:48.86,Default,,0000,0000,0000,,Nonetheless, only in the last ten years has there been quite a “fracking boom”,
Dialogue: 0,0:00:48.86,0:00:51.13,Default,,0000,0000,0000,,especially in the USA.
Dialogue: 0,0:00:51.13,0:00:57.63,Default,,0000,0000,0000,,This is because most conventional natural gas sources in America and on the European continent have been exhausted.
Dialogue: 0,0:00:57.63,0:01:03.30,Default,,0000,0000,0000,,Thus prices for natural gas and other fuels are rising steadily.
Dialogue: 0,0:01:03.30,0:01:10.66,Default,,0000,0000,0000,,Significantly more complicated and expensive methods, like fracking, have now become attractive and profitable.
Dialogue: 0,0:01:10.66,0:01:17.10,Default,,0000,0000,0000,,In the meantime, fracking has already been used more than a million times in the USA alone.
Dialogue: 0,0:01:17.10,0:01:22.50,Default,,0000,0000,0000,,Over 60% of all new oil and gas wells are drilled by using fracking.
Dialogue: 0,0:01:22.50,0:01:26.80,Default,,0000,0000,0000,,Now let’s take a look at how fracking actually works:
Dialogue: 0,0:01:26.80,0:01:31.80,Default,,0000,0000,0000,,First, a shaft is drilled several hundred meters into the earth.
Dialogue: 0,0:01:31.80,0:01:37.10,Default,,0000,0000,0000,,From there, a horizontal hole is drilled into the gas-bearing layer of rock.
Dialogue: 0,0:01:37.10,0:01:42.10,Default,,0000,0000,0000,,Next, the fracking fluid is pumped into the ground using high-performance pumps.
Dialogue: 0,0:01:42.10,0:01:46.05,Default,,0000,0000,0000,,On average, the fluid consists of 8 million liters of water
Dialogue: 0,0:01:46.05,0:01:50.13,Default,,0000,0000,0000,,which amounts to about the daily consumption of 65,000 people.
Dialogue: 0,0:01:50.13,0:01:55.66,Default,,0000,0000,0000,,plus several thousand tons of sand and about 200,000 liters of chemicals.
Dialogue: 0,0:01:55.66,0:02:01.05,Default,,0000,0000,0000,,The mixture penetrates into the rock layer and produces innumerable tiny cracks.
Dialogue: 0,0:02:01.05,0:02:05.26,Default,,0000,0000,0000,,The sand prevents the cracks from closing again.
Dialogue: 0,0:02:05.26,0:02:07.96,Default,,0000,0000,0000,,The chemicals perform various tasks
Dialogue: 0,0:02:07.96,0:02:10.46,Default,,0000,0000,0000,,among other things, they condense the water,
Dialogue: 0,0:02:10.46,0:02:11.96,Default,,0000,0000,0000,,kill off bacteria
Dialogue: 0,0:02:11.96,0:02:14.88,Default,,0000,0000,0000,,or dissolve minerals.
Dialogue: 0,0:02:14.88,0:02:18.22,Default,,0000,0000,0000,,Next, the majority of the fracking fluid is pumped out again.
Dialogue: 0,0:02:18.22,0:02:22.05,Default,,0000,0000,0000,,And now the natural gas can be recovered.
Dialogue: 0,0:02:22.05,0:02:26.34,Default,,0000,0000,0000,,As soon as the gas source is exhausted, the drill hole is sealed.
Dialogue: 0,0:02:26.34,0:02:32.58,Default,,0000,0000,0000,,As a rule, the fracking fluid is pumped back into deep underground layers and sealed in there.
Dialogue: 0,0:02:32.58,0:02:37.22,Default,,0000,0000,0000,,However, fracking is also associated with several considerable risks.
Dialogue: 0,0:02:37.22,0:02:41.10,Default,,0000,0000,0000,,The primary risk consists in the contamination of drinking water sources.
Dialogue: 0,0:02:41.10,0:02:44.10,Default,,0000,0000,0000,,Fracking not only consumes large quantities of fresh water,
Dialogue: 0,0:02:44.10,0:02:49.22,Default,,0000,0000,0000,,but in addition the water is subsequently contaminated and is highly toxic.
Dialogue: 0,0:02:49.22,0:02:56.22,Default,,0000,0000,0000,,The contamination is so severe that the water cannot even be cleaned in a treatment plant.
Dialogue: 0,0:02:56.22,0:02:59.96,Default,,0000,0000,0000,,Even though the danger is known and theoretically could be managed,
Dialogue: 0,0:02:59.96,0:03:06.34,Default,,0000,0000,0000,,in the USA already sources have been contaminated due to negligence.
Dialogue: 0,0:03:06.34,0:03:09.62,Default,,0000,0000,0000,,No one yet knows how the enclosed water will behave in the future,
Dialogue: 0,0:03:09.62,0:03:14.30,Default,,0000,0000,0000,,since there have not yet been any long-term studies on the subject.
Dialogue: 0,0:03:14.30,0:03:17.58,Default,,0000,0000,0000,,The chemicals used in fracking vary from the hazardous to the
Dialogue: 0,0:03:17.58,0:03:24.74,Default,,0000,0000,0000,,extremely toxic and carcinogenic, such as benzol or formic acid.
Dialogue: 0,0:03:24.74,0:03:32.58,Default,,0000,0000,0000,,The companies using fracking say nothing about the precise composition of the chemical mixture.
Dialogue: 0,0:03:32.58,0:03:39.18,Default,,0000,0000,0000,,But it is known that there are about 700 different chemical agents which can be used in the process.
Dialogue: 0,0:03:39.18,0:03:43.54,Default,,0000,0000,0000,,Another risk is the release of greenhouse gases.
Dialogue: 0,0:03:43.54,0:03:47.42,Default,,0000,0000,0000,,The natural gas recovered by fracking consists largely of methane,
Dialogue: 0,0:03:47.42,0:03:53.46,Default,,0000,0000,0000,,a greenhouse gas which is 25 times\Nmore potent than carbon dioxide.
Dialogue: 0,0:03:53.46,0:03:57.46,Default,,0000,0000,0000,,Natural gas is less harmful than coal when burned.
Dialogue: 0,0:03:57.46,0:03:59.38,Default,,0000,0000,0000,,But nonetheless, the negative effects of fracking
Dialogue: 0,0:03:59.38,0:04:02.13,Default,,0000,0000,0000,,on the climate balance are overall greater.
Dialogue: 0,0:04:02.13,0:04:07.50,Default,,0000,0000,0000,,Firstly, the fracking process requires\Na very large consumption of energy.
Dialogue: 0,0:04:07.50,0:04:11.74,Default,,0000,0000,0000,,Secondly, the drill holes are quickly exhausted and it is necessary to drill
Dialogue: 0,0:04:11.74,0:04:16.63,Default,,0000,0000,0000,,fracking holes much more frequently than for classical natural gas wells.
Dialogue: 0,0:04:16.63,0:04:24.50,Default,,0000,0000,0000,,In addition, about 3% of the recovered gas is lost in the extraction and escapes into the atmosphere.
Dialogue: 0,0:04:24.50,0:04:27.26,Default,,0000,0000,0000,,So how is fracking and its expected benefits to be assessed
Dialogue: 0,0:04:27.26,0:04:31.50,Default,,0000,0000,0000,,when the advantages are balanced against the disadvantages?
Dialogue: 0,0:04:31.50,0:04:34.26,Default,,0000,0000,0000,,When properly employed, this technique offers one way
Dialogue: 0,0:04:34.26,0:04:41.05,Default,,0000,0000,0000,,in the short to medium term for meeting our demand for lower-cost energy.
Dialogue: 0,0:04:41.05,0:04:44.63,Default,,0000,0000,0000,,But the long-term consequences of fracking are unforeseeable
Dialogue: 0,0:04:44.63,0:04:49.26,Default,,0000,0000,0000,,and the risk to our drinking water thus should not be underestimated.