Human Carbon Footprint
Human Carbon Footprint is a CGTN documentary that tells the story of human development and carbon emissions. This 54-minute documentary takes the viewers on a global journey to explore how carbon has shaped our energy-intensive modern world and lifestyles, and what we need to do to wean ourselves off fossil fuels and ensure humanity's lights stay on.
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🛠️
LifestyleTranscript
00:00 Do you know that every day our species consumes more than 1.5 million terajoules of energy?
00:10 That's equals to 28,000 times the atomic explosion in Hiroshima.
00:19 For those who live in a modern society, most of the energy we use is in the form of electricity.
00:28 Shapeless and soundless.
00:31 Making energy a bit like air is all around you, but you cannot feel it.
00:38 You take it for granted.
00:41 Until this summer, when I visited Dringer in Inner Mongolia of China,
00:55 I realized that I had never seen the primary form of our energy,
01:00 so concrete and solid, before they were extracted from deep inside the earth's crust.
01:08 The color layer is about 60 meters.
01:17 Below that is the coal layer, which is about 35 meters.
01:23 Heydaigo, the largest open-pit coal mine in Asia,
01:29 is known for its high-quality coal and rather shallow reserve.
01:34 To better access the coal, Chen Hao's team needs to do some preparation.
01:42 Every time they mine, they need to put in 2 million tons of coal.
01:51 We are walking on 1,500 tons of an explosive called ANFOL,
01:57 which will move the rock layer under our feet,
02:04 horizontally into a nearby deep valley.
02:08 The coal will be about 500,000 to 600,000 tons,
02:11 and will be stored in the pit,
02:14 which will save us the mining process.
02:17 This is a very advanced process.
02:20 Ready to detonate.
02:22 5, 4, 3, 2, 1.
02:26 You ready?
02:28 First, you see it.
02:32 In two seconds,
02:35 you hear it.
02:38 Here comes the high-density fuel that powers our civilization.
02:49 A kilogram of coal can produce from 3,000 to over 6,000 kilocalories of heat.
02:58 And there's a fascinating process that goes on.
03:03 The process of energy emitting depends on the combination of carbon, hydrogen, and oxygen.
03:10 Carbon is the major source of heat during burning.
03:16 Today, fossil fuels still supply 84% of the world's energy.
03:24 A leading contributor to the rising level of greenhouse gases,
03:30 the international community agrees that we are on a path towards disaster.
03:35 We are on a highway to climate hell,
03:38 with our foot still on the accelerator.
03:42 A journey that can only be stopped by weaning ourselves off of our fossil fuel thirst.
03:48 We must reduce carbon emission on the one hand,
03:52 and remove those in the atmosphere on the other.
03:57 Complementary efforts to help us reach net-zero emissions,
04:03 or carbon neutrality,
04:06 when mankind's carbon footprint will fade from the planet.
04:11 From this coal pit, my colleagues and I will embark a global journey
04:17 to find out how this most difficult transition will be done,
04:23 while making sure mankind's lights stay on.
04:50 Throughout the history of human civilization,
04:54 we've always had a big appetite for energy of higher density.
05:00 From wood to charcoal,
05:05 from fossil fuels to nuclear,
05:10 this trend never changed,
05:15 until the climate crisis forced humanity to reverse course for the first time.
05:22 In one hour, the Earth's atmosphere received enough sunlight
05:38 to power the electricity needs of every human being for a year.
05:44 But because the Earth is so vast,
05:46 that translates to about only 1,000 watts of energy per square meter of surface.
05:53 Given the 20% efficiency of a solar panel,
05:56 that means you put one square meter panel under the sun,
06:00 and wait for about five hours,
06:03 then you can get one kilowatt hour.
06:06 That's one unit electricity on your bill.
06:10 In comparison, a power plant can finish this job by burning just 300 grams of coal.
06:15 But now we have to rely on such inefficient ways to obtain such diluted energy.
06:22 To compensate, we have to go big.
06:28 Very big.
06:38 When over 600 square kilometers of desert are covered with solar panels,
06:43 it's a different story.
06:46 You are looking at one of the world's largest solar farms.
06:51 But it's just a fraction of a more ambitious plan of Qinghai,
06:57 which includes 2,000 square kilometers of an installed capacity of 154 million kilowatts,
07:07 equivalent to seven Three Gorges power stations.
07:11 In fact, China has 323 gigawatts of solar capacity,
07:20 around a third of the entire global total.
07:24 But more importantly, mass production and research progress here
07:30 have cut the panel price by 75% in 10 years.
07:36 But that doesn't mean we can solve the climate crisis by covering an entire desert.
07:42 Engineering and economics aside,
07:45 a massive solar farm will absorb more heat than the natural sand,
07:50 change the region's climate, and dramatically transform the ecological landscape.
07:55 The good news is we have a lot of desert,
08:03 we have a lot of desert and unused land around the world.
08:06 But the bad news is few people live there.
08:09 So we need to invest more in grids to transfer the energy to people who need it.
08:14 How can we bring renewable energy closer to us?
08:18 Where space is at a premium,
08:26 wind turbines are a better option.
08:32 A report by the International Energy Agency has also found
08:36 that a growth of wind power generation was the highest among all renewable sectors in 2021.
08:43 But people want those giant blades to be smaller, shorter, and quieter.
08:49 In Madrid, our team met David Yanez,
08:58 whose solution is to just get rid of them.
09:25 November 1940.
09:27 The Tacoma Narrow-Spread Disaster in the US taught people a lesson about a destructive phenomenon
09:34 called vortex-induced oscillation.
09:37 Ever since, engineers have tried their best to avoid that force of nature.
09:43 Until they found they could turn it to their advantage.
09:49 The wind comes in this direction.
09:54 The wind produces a physical phenomenon here,
09:56 in which the pressure is high and low in both sizes alternatively.
10:01 So at the end, vortices are produced.
10:04 Prototypes are tested in this wind tunnel.
10:10 Nobody has investigated how to enhance this process
10:21 or how to absorb much amount of energy from the wind in this way.
10:25 The key to harnessing wind power in such a rare way is the alternator inside.
10:33 Unlike alternators in traditional wind turbines,
10:39 which include a magnet and copper wire coil,
10:42 the vortex alternator is driven by just a carbon fiber rod.
10:48 At Comius Pontifical University,
10:50 scientists are testing all kinds of materials to their limit
10:55 to see if they can withstand the oscillation,
10:59 including this carbon fiber rod.
11:03 We're pulling the sample.
11:06 So basically what we're checking is how much does the material stand.
11:13 The force we're applying, the whole material, the polymeric matrix,
11:17 as well as the fibers are stretching to some point.
11:22 Did it break?
11:28 It broke!
11:30 It's failed!
11:32 At least we know the limit.
11:37 It's very strong.
11:39 And very flexible.
11:42 It's very flexible and it can survive the oscillation.
11:44 It is much more strong than what is needed for the application.
11:48 One day, this technology will help us move the wind farm into the city,
11:53 occupying your roof or balcony.
11:56 Competition for available land is more severe in populated areas.
12:09 Well, today, solar panels could be found anywhere in China.
12:12 Rooftops are just old-fashioned.
12:15 If humanity wants to avoid the worst of climate change,
12:19 we need to better get more creative about where we put solar panels.
12:24 Under those panels is actually Liu Zhenhua's fish pond.
12:32 This is a pig's tail.
12:34 It's worth hundreds of thousands of yuan.
12:37 It's worth it.
12:39 The solar power above has little effect on the seafood.
12:45 And selling electricity can make money.
12:48 It's a very good way to make money.
12:51 It's a very good way to make money.
12:54 It's a very good way to make money.
12:58 And selling electricity can make money.
13:01 It's a win-win.
13:03 Compared to a massive solar farm in the remote desert,
13:08 this distributed system near people is a new trend.
13:12 For Mr. Liu, it's a good day for harvesting seafood.
13:25 And a good day for harvesting energy.
13:28 Whether it's the innovative wind power in Madrid,
13:33 or a creative fish pond host solar farm in Changzhou,
13:38 they both bring renewable energy to populated areas.
13:42 Otherwise, we need to transmit power from far, far away.
13:46 There is an abundance of renewable energy out there.
13:51 But power lines are massive black holes of energy.
13:56 Praying for safety.
14:06 Paulo Chaves was suing Go Up to his workplace at a height of 57 meters.
14:18 Treading on aluminum cables, transmitting energy at 800,000 volts.
14:23 Double the voltage of conventional lines.
14:47 The line deserves special care.
14:49 At one end, in the heart of the Amazon jungle in Brazil's northern state of Pará,
14:55 lies Develo Monte, the country's second largest hydropower station.
15:01 At the other end is Rio de Janeiro, the mega city in the country's southeast.
15:14 This 2,000 kilometer long line has to deliver 4,000 megawatts of energy
15:20 to feed 70% of the power need there.
15:24 Whether Rio can embrace more renewable energy is determined by transmission.
15:30 It's impossible for the usual alternate current transmission
15:37 because the wire resistance will generate considerable heat over such a long journey
15:43 and resulting in a huge loss of energy.
15:46 Well, Ohm's Law provides a solution.
15:49 You can apply a very high voltage
15:53 in order to transfer energy at super low current value,
15:59 thereby minimizing the energy loss over long distance.
16:04 Direct current is better suited for the long distance job.
16:11 At the converter stations, voltage will be raised to 800,000 volts,
16:15 which qualifies as ultra high voltage,
16:18 and has to the destination without any stops.
16:22 This is Develo Monte's Chinese twin in Jiangsu.
16:28 The maintenance schedule gave me, and anything else that can breathe,
16:33 a chance to get into the very heart of it.
16:37 Well, if the converter station is a still jungle,
16:41 here, the valve hole, is the holy temple,
16:46 hidden deep in the forest.
16:49 That's where all the magic happens.
16:53 Electricity is transferred at a speed of light, 300,000 kilometers per second.
17:01 The 2,000 kilometer journey between two converter stations takes only 0.007 seconds.
17:08 First, the power station generates 500 kilovolts AC.
17:13 It will be turned into 800 kilovolts ultra high voltage DC,
17:18 and the first converter station then has to the destination.
17:22 And after thousands of kilometers of transmission,
17:28 AC arrives here, where all systems are instantly engaged
17:32 to convert it back into AC, then transferred to the local grid.
17:37 All of this needs to be done in a flash,
17:41 within those valves where a core component called thyristors is within.
17:47 At the same time, tremendous heat will be generated,
17:51 so those cooling pipes will be responsible to cooling the whole system down.
17:57 Without them, the steel giants will be melted down one by one.
18:03 A masterpiece of engineering.
18:07 We have the power centers launched from the consumer centers.
18:16 Like I mentioned, this is a very useful technology in the way to reduce these losses.
18:23 It's the most efficient way to transmit this kind of energy.
18:27 Ultra high voltage will be reduced before the power enters real, for mission accomplished.
18:34 But here in Suzhou city, I saw another type of UHV, which shared the city with people.
18:51 The TKR direct current is a remote-controlled power plant.
18:55 There is only one starting point and one ending point.
18:58 The TKR direct current can have an ending point at any time.
19:02 The city's demand for electricity can be directly supplied to the power plant.
19:07 The river is running normally.
19:11 No boats are littering, no sand mining, no work is done.
19:18 Here, along this section of the Yanzu River, there is not just one megalopolis, but a group of them.
19:25 A 1000 kV AC line needs to cross the river to complete a UHV loop.
19:35 The river is a busy area, so the ships are busy transporting goods.
19:40 This will take up a lot of ship's resources, so we use the river to cross the river.
19:46 The tunnel is 5468.5 meters long.
19:51 The upper part of the tunnel is the river.
19:54 The dangers of ultra high voltage have engineers here on constant alert.
20:02 They have to guard against any small changes.
20:05 Temperature, humidity, abnormal discharge, and the forces of nature.
20:14 The tunnel is 543.5 meters long.
20:17 The tunnel is 543.5 meters long.
20:19 There is a thing like this in each section.
20:27 This is a tensioner.
20:29 There are 503 tensioners like this in the entire pipe.
20:33 This tensioner absorbs heat and coolant,
20:38 as well as the gravity of the tunnel.
20:44 This is like the tunnel in the middle of a straw.
20:48 The sturdy tunnel is not as motionless as it seems.
20:55 It is moving.
21:01 Dragged by the forces of nature.
21:13 It changes with the tide of the Yangtze River.
21:16 So the tunnel is changing slowly.
21:20 It is sinking.
21:23 This is almost the only chance for humans to get so close to 1000 kilovolts of ultra high voltage.
21:32 Thanks to the protective devices.
21:35 Without them, this voltage would break through the air in between and reduce us to ashes in seconds.
21:43 Thankfully, I can get close enough to touch it.
21:48 If it is quiet enough, you can hear the hum of energy.
21:53 Inside the insulated pipeline,
22:01 filled with dielectric gas,
22:05 energy flows safely through the Yangtze River.
22:15 This underwater tunnel and UHV infrastructure has connected Suzhou and Nantou over there,
22:24 and beyond Nanjing, Hefei, Hangzhou, and Shanghai.
22:32 A giant energy loop has been built to encircle one of the world's most important city groups and manufacturing hubs.
22:41 The East China Sea has always been our core.
22:44 Without the external power supply, we need to build a lot of things locally.
22:49 We can only rely on coal power.
22:52 After using our clean energy, we can reduce our local power plants.
22:57 In China, over 30 UHV lines are in operation,
23:03 linking renewable energy to the energy of the world.
23:08 And over 50 UHV lines are in operation,
23:11 linking renewable energy in the country's west to wider consumers on the east coast.
23:18 But not all renewable electricity can get on those lines,
23:25 because of the bad temper of solar and wind sources.
23:29 The power grid's job is to balance supply and demand at the speed of light all the time,
23:37 so the plants generate not too much, not too little.
23:40 Fossil fuels and even hydro can instantly adjust to output as desired.
23:47 But solar and wind are like untamed horses, they just run wild.
23:53 So if too much or too little renewable energy enters the system when not needed,
24:00 the grid will fluctuate or even collapse.
24:05 That's when curtailment happens, a purposeful waste of solar and wind energy.
24:12 Most countries tackle this by keeping more reliable sources of energy production in reserve.
24:25 [Music]
24:32 [Speaking Chinese]
24:36 [Music]
24:42 [Speaking Chinese]
24:55 The new challenge for this powerful generator is how to keep a low profile.
25:02 [Speaking Chinese]
25:15 But if the wind drops, or when the sun deeps beneath the horizon,
25:22 they have to be ready to ramp up their production.
25:26 But in the end, it's still fossil fuel.
25:31 [Music]
25:33 Pump storage hydropower can also help.
25:37 [Music]
25:40 Access electricity is used to pump water to the top of these dams,
25:45 where it is stored as potential energy.
25:49 When it is needed, the water is released to drive turbines.
25:53 [Music]
26:04 The largest one of this kind, China's Fengding Power Station,
26:09 proves its ability to help the 2022 Winter Olympics run on 100% renewable energy,
26:17 in line with China's promise for a Green Games.
26:20 [Music]
26:24 However, batteries are catching up as the most scalable type of great-scale storage.
26:32 CATL has supplied over 30% of global EV batteries.
26:37 Now their products have a new place to go.
26:42 The solar and wind farms to hook up new energy with the grid.
26:47 [Music]
26:49 But for now, this combination isn't cost-effective.
26:53 Because lithium-ion batteries have a relatively low energy density,
26:58 a basic science breakthrough is needed.
27:02 [Music]
27:04 And assembly lines have seen some inspiring improvement.
27:10 [Music]
27:12 Thinner foil means more electrode material could be packed in the same size battery cell,
27:36 increasing energy density.
27:39 How thick is 4.5 microns?
27:43 From raw materials to a cell like this,
28:04 emissions per kilowatt-hour battery capacity, that's about 60 kilograms.
28:09 Pan Xuexing's job is to track the carbon footprint.
28:15 [Chinese]
28:42 If a battery is what we use to tackle climate change,
28:46 it better be a product of net zero emissions.
28:50 But in the eyes of Lu Wengang,
28:53 the future of grid storage has already been produced.
28:58 [Chinese]
29:00 [Music]
29:14 Park in,
29:26 plug in,
29:29 and the system.
29:30 And Lu Wengang can take over the batteries of his colleague's 300 EVs.
29:35 Cars will instantly become storage for 2 megawatts of solar panels,
29:40 powering the entire factory.
29:43 [Chinese]
29:56 With those EVs and solar panels, his factory will become a microgrid,
30:01 which is a part of the city grid,
30:05 participating in the more complex interaction.
30:09 Energy flows through the cars,
30:12 and when the shift is over, people drive home and charge the EVs.
30:17 [Music]
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30:51 By 2040, China could have 300 million EVs,
30:56 with a combined battery 20 billion kilowatt-hour capacity,
31:01 equal to the electricity consumed in China for a day.
31:06 [Beep]
31:08 [Chinese]
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31:21 We are witnessing a revolution,
31:25 but fossil fuels won't be gone overnight,
31:28 so carbon emissions will be still there.
31:32 But if we can't store the electricity,
31:35 can we store CO2?
31:38 [Music]
31:43 Iceland is one of the most highly active geothermal countries in the world.
31:48 [Music]
31:50 At the Halle-Skadi power plant just outside of EirĂkvek,
31:53 steam from underground creates the power,
31:56 but also brings CO2 with it.
31:59 [Chinese]
32:01 Dr. Eda Eredahtur is the project manager of CarbFix,
32:05 pioneering a process to bury that CO2.
32:09 This power plant, for example, only emits 3% of the CO2.
32:14 Cold-burning power plants of the same size emit.
32:17 Last year, we captured and injected a third of the CO2 emissions from the power plant.
32:22 So how do they capture CO2?
32:25 It seems very simple.
32:28 Steam and hot water are pumped to the surface to generate electricity.
32:34 The steam drives the turbines and is then cooled and condensed.
32:39 Gases like carbon dioxide and hydrogen sulfide from underground
32:44 are pumped out of the turbine into the scrubber and showered with pure water.
32:49 Here, CO2 and other gases are dissolved and non-water-soluble gases are vented.
32:56 The CO2 mixture is then piped over to those igloos,
33:03 which protect the 2-kilometer-deep injection well and equipment from the harsh winter here.
33:11 Nature plays a big part.
33:13 Basalt rock is cooled lava and contains calcium, magnesium and iron,
33:19 which reacts with the CO2 mixture, forming solid calcium carbonate in the rocks.
33:26 So this is a core we drilled into the storage formation a few years back.
33:31 And then we have the white veins and spots in between, and that's mineralized CO2.
33:38 And it turns out that what we inject is turned into rock like this in less than two years.
33:43 So it's a very efficient and effective process, permanently getting rid of CO2.
33:49 Iceland is now looking at applying this technology to heavy industrial plants.
33:55 Wherever there is basalt rock, this process can work.
34:00 It's the most common rock type on Earth, covering around 10% of continents.
34:07 And most areas within the ocean basins are underlined by basalt.
34:13 On a big scale, we looked at all of the oceanic ridges.
34:17 Of course, it's probably not economically to do it,
34:21 but you could take all the CO2 from burning of all fossil fuels that we know of on Earth.
34:28 But the ocean can have one big advantage.
34:34 The large amount of water needed for this process.
34:37 It takes around 25 tons to convert one ton of CO2.
34:43 So Professor Gislassen is eyeing this abounded resource to test the CO2 mineralization in seawater.
34:52 What we're doing is just a drop in the bucket.
34:55 Presently we are emitting about 40 gigatons per year of CO2.
35:01 We have to be extremely focused to get going, to capture CO2 as fast as we can.
35:07 And then later on, the second half of this century, we have to clean it from air, because we're not doing it fast enough.
35:13 What can help us move faster is an ancient way of Mother Nature.
35:30 From day one for plants, they soak up sunlight and carbon dioxide in the air to create their own fuel in the leaves,
35:39 in a process called photosynthesis, a way of nature to capture carbon.
35:46 We need trees.
35:49 A lot of trees.
35:59 My name is Gay Cullen and I live here in the savannah.
36:02 Having been a pilot for over 43 years and flown all over Africa, you see that this area, the trees, are just being denuded everywhere.
36:16 Like many other areas in Africa, Kenya is losing thousands of native trees every year.
36:25 One of the main drivers is the need for charcoal.
36:33 Made by burning some certain types of trees, many people can't afford or get access to electricity.
36:40 Teddy Kenyanjan brings an ingenious way to reverse the loss with an unexpected ally, charcoal itself.
36:52 Our species choice is always, what are people cutting down for charcoal?
36:56 Bring all of the seeds to chardust, where they get made with our proprietary technology that we've invented into seed balls.
37:05 They collect native tree seeds and mix them with chardust.
37:10 With the carbon coat, the seeds would not be eaten by passing animals.
37:20 And when the rains arrive, the charcoal shell will be washed down to become nutrients.
37:26 Charcoal dust, I know, is a very good amendment for the soil. High porosity holds nutrients, holds water, microbes and bacteria.
37:35 Seed balls will be distributed to places where forest is vanishing due to charcoal making.
37:44 And just throw the seed balls.
37:47 And let them grow.
37:52 And you can do it with more creative ways.
38:01 For the hard to reach areas, seed balling becomes seed bombing.
38:09 Whistling is a way of communicating with the environment.
38:15 And the other tree that you see around here is the desert date.
38:19 I think seed balling is definitely the way to go.
38:23 It's a way of communicating with the environment.
38:27 It's a way of communicating with the environment.
38:31 It's a way of communicating with the environment.
38:35 It's a way of communicating with the environment.
38:40 It's a way of communicating with the environment.
38:45 And the more we can do it from the air, and learn how to do it from the air, we can spread it wider.
38:50 Kenya has only 7.4% forest to cover, well under the 10% minimum recommended by the UN.
38:59 Since 2016, over 26 million seed balls have been thrown on the ground with the hope to turn things around.
39:10 China
39:12 China took action earlier.
39:18 Now it has the largest area of artificial forest in the world, accounting for more than one third.
39:25 But monoculture makes it fragile.
39:33 In Qianjiangyuan National Park, young scientists are about to take some special pictures for the trees.
39:39 A basic step for a more ambitious goal to upgrade the artificial forest.
39:46 We use the laser to record the three-dimensional structure of the forest.
40:00 How to use the laws of nature to build artificial facilities and systems.
40:06 It can't be a single species.
40:09 But which species can grow together to achieve efficient solid carbon?
40:16 It's a basic research to provide a plan.
40:19 To achieve biodiversity protection and climate change reduction.
40:26 China
40:28 Lasers help scientists understand natural forests in a whole new way.
40:43 China
40:45 China
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40:51 China
40:54 China
40:57 Research in forest systems
41:00 Research in forest systems
41:03 Research in forest systems
41:06 Research in forest systems
41:10 China
41:12 But why and how biodiversity could improve carbon storage?
41:19 Lu Xiaojuan manages the decade-long experiment.
41:24 Not in the lab, but in nature.
41:28 The L24-0515, a model of a quadrilateral tree, has a diameter of 11.3 cm.
41:39 About half of the weight of trees is carbon.
41:42 The bigger they grow, the more carbon they capture.
41:46 She compares sample lands from monoculture forests to forests with 2 to 24 tree species.
41:54 A diverse plot with 24 species is the level of natural forest in Chenjiangyuan.
42:04 We compared the amount of carbon in the forest with 16 species of plum trees.
42:09 We found that after 8 years, the carbon in 16 species is twice that of the forest.
42:14 China
42:17 Researchers have found that a diversified forest can establish an invisible network.
42:26 China
42:29 China
42:33 The trees intertwine to exchange water and microbes.
42:37 China
42:40 The canopy crosses and they avoid each other to maximize sunlight intake.
42:47 China
42:50 And insects move through a network of leaves.
42:54 China
42:56 They form one entity.
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45:00 All of those efforts aim to bring everyone on this planet, our kids especially,
45:07 a quality of life that is as good as or better than what we have now.
45:15 In a short time, renewable energy could be part of the solution,
45:19 but our team believes there is a far more promising long-term alternative.
45:27 To find future energy for humans, an international collaboration of scientists is trying to recreate the power of the sun on Earth.
45:38 Nuclear fusion is considered the holy grail of an unlimited supply of clean energy.
45:50 35 countries from around the world have come together to create a sustainable fusion reaction,
45:57 designed to produce more energy than it consumes.
46:01 It's called ITER, which is Latin for "the way".
46:09 There are four Asian countries, China, Japan, South Korea, and India.
46:14 Europe is made up of all EU members, and the United States and Russia are the West.
46:20 The goal is to build a fusion reactor with a power of 500,000 kilowatts.
46:26 This reactor will be able to operate for a long time,
46:33 and will be able to generate electricity and build a foundation.
46:37 At its simplest, the sun is a huge glowing sphere of hydrogen and helium.
46:44 Its extreme temperatures strip hydrogen nuclei of their electrons,
46:50 leaving the protons and electrons moving around freely in what is known as a plasma.
46:57 Because plasmas are a mass of charged particles, they can be influenced by magnetic fields,
47:05 which is key to achieving fusion here on Earth.
47:09 And that happens inside a containment vessel known as a tokamak,
47:16 built to hold plasmas hotter than those found in the sun.
47:21 With a very powerful magnetic field, a tokamak can actually create the temperatures needed for fusion to occur.
47:32 Right now, ITER is still a giant construction project.
47:37 We're going down to the first basement and then the second basement.
47:41 But already spectacular in itself.
47:45 So here we come into the tokamak pit, and this is where you appreciate the scale of the tokamak.
47:50 This entire space will be full from ground to ceiling with the tokamak.
47:54 One of the other things about fusion is that making the plasma bigger
48:00 is easier to control and easier to make the reaction.
48:02 Because if you imagine you have a volume of plasma you're trying to heat,
48:06 then the bigger you make it, the better the surface area, so you lose less heat wasted.
48:11 So the bigger you can make your tokamak, the easier it is to do fusion.
48:14 So that's why the scale of ITER.
48:17 The efficiency and performance of the tokamak is key,
48:23 and that depends on how the plasma is created.
48:29 So as we see here, there's a central column that's like a transformer.
48:32 So you have a gas, you give some energy to it, the electrons will start to separate from this gas,
48:38 and once these electrons separate, they will further gain more energy,
48:42 and you know they will ionize another hydrogen, let's say.
48:47 It's a chain reaction and you will finally get a plasma.
48:55 The massive magnet will help control the plasma in the tokamak,
48:59 creating a magnetic field strong enough to lift an aircraft carrier clean out of the ocean.
49:05 ITER is designed to yield this plasma a tenfold return on power,
49:12 or 500 megawatts of fusion power from 50 megawatts of input.
49:17 This experiment is highly uncertain.
49:22 We are working on a scientific experiment on existing equipment.
49:25 We are comparing data, including the superconductor,
49:29 and we have achieved a result of 1020 seconds.
49:32 And our new-built 2M turbine
49:37 has achieved a single-shutdown in a very short time.
49:41 We are also using our own solution to modify the original ITER solutions.
49:49 At Calhoun's Center for Fusion Energy, scientists have the world's largest tokamak,
49:55 Jet.
49:57 Jet is a sort of a proper type of ITER.
50:01 ITER has been built on the success of Jet.
50:04 Today, scientists are going to generate plasma for real.
50:10 So this is a Jet experiments control room.
50:17 It's like science fiction, but it's not science fiction, it's actual science.
50:21 Every piece of information we get is vital to advance fusion science.
50:28 And this is one of the very important pieces of the puzzle
50:33 that we need to create the scientific knowledge to run a fusion experiment like ITER.
50:46 What's that sound?
50:47 What you've just heard is the loudspeaker indicating that we start a new countdown.
50:53 It's almost like launching a rocket.
51:05 [Rocket launching]
51:07 Five, four, three, two, one.
51:22 [Rocket launching]
51:25 [Rocket launching]
51:28 [Rocket launching]
51:33 [Rocket launching]
51:35 The climate is always changing.
51:48 Earth is not experiencing its first global warming.
51:54 [Explosion]
51:56 How bad can it be?
52:22 In fact, not bad.
52:25 Some species disappeared, and some others occupied the niches.
52:49 On the list of newborns is this little creature.
52:54 The body structure reveals it was a good tree climber.
53:01 But here, bones that made up his feet are the focus.
53:07 We found that his feet were his best feature.
53:10 Theoretically, he should be like a monkey with glasses.
53:14 But we found that he had the same feet as a human.
53:18 He happened to be standing between the monkey with glasses and the human.
53:22 Meet Achilles,
53:26 the oldest known primate fossil,
53:30 marking that great evolutionary moment of divergence.
53:35 [Water rushing]
53:37 In the long years to come, the heel bones of some of his offspring would get shorter,
53:53 and this offspring would leave the trees to walk upright on the ground,
53:58 leaving a footprint like this.
54:03 Yes, Achilles was our ancestor of some sort.
54:08 Achilles made his debut in the global warming.
54:16 Today, we have created another warming by our own hands.
54:23 Can humanity hanging there?
54:31 Or will it fade away?
54:34 Earth doesn't need saving.
54:38 We do.
54:42 [Music]
54:47 [BLANK_AUDIO]