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High-Tech Climate Solutions
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0:01
Giant CO2 vacuum cleaners, miracle dust in the fields,
0:07
algae farms in Africa. High-tech efforts to stop global warming.
0:13
Ten years from now is too late. We need to start now and research it from all angles, what is most effective, what can be implemented later? But which innovations can really mitigate the climate crisis? And which ones should be used with caution?
0:31
We can't take one problem we humans have created and add another on top, I find that very unappealing.
0:38
High-tech innovations are breaking new ground. But can they REALLY stop climate change?
0:58
Marcel Rensmann is doing the rounds in his garden in western Germany’s Rhine-Hesse region. Most of his plants have recovered from last summer’s heatwave.
1:09
The lawn which was exposed to the sun turned into a field of stubble. It looked nothing like a lawn anymore. It looked like it was in southern Spain and it hadn’t rained for 30 years. It was alarming. At one point we just stopped watering it, the drought stress was too much. The consequences of climate change are palpable. Both here in the garden, and more dramatically elsewhere in the world. Marcel Rensmann believes that something has to change, on a small as well as a large scale.
1:37
There’s a wide range of solutions. There’s no one answer. It's not just down to electromobility, or rainwater management, or giving up meat. There are so many constructive solutions that work well.
1:49
Marcel will show us later which of these solutions he’s involved in professionally.
1:59
Intensive research into climate change mitigation has been conducted for several years now.
2:06
In Iceland, nature offers a solution with an ideal combination of ingredients: geothermal energy, volcanic rock and plenty of water.
2:25
Like a spaceship stranded in the middle of nowhere, the Orca carbon-capture plant is the first of its kind.
2:33
Orca uses giant collectors to filter carbon dioxide, a harmful greenhouse gas, from the atmosphere.
2:44
The filter captures the CO2 molecules while releasing the cleaner air back in the atmosphere and once the filters are full you close up the compartments that the filter is in, and you apply heat at around a 100 degrees Celsius which releases the CO2 which we can capture and collect. The heat is produced renewably from a geothermal power station. The Orca plant has collected 4,000 tons per year so far, the equivalent of the greenhouse gas emissions of 360 people in Germany.
3:17
It's not a lot. I mean the globe emits around 36 billion tons of CO2 per year. But this is a new technology. We went from capturing milligrams to kilograms to tons to 4,000 tons and so we are on our way to a huge and massive scale-up.
3:36
More plants will be built soon, not just here in Iceland. Wherever there is volcanic rock, these plants can be built, as the CO2 can be permanently stored in the rock.
3:49
That's what's happening under these igloos nearby.
4:00
Ólafur Teitur Guðnason explains to us exactly how. The company he works for developed the process.
4:09
It’s simple - at least in principle.
4:15
So this large pipe we are looking at is a pipe from the geothermal power plant injecting geothermal water into the ground - 2 km deep into the geothermal area. And what Carbfix does is to actually borrow that pipe and inject our CO2 charged water coming through this smaller pipe into the bigger one and also going down into the earth, where the CO2 from the water is mineralized in less than two years.
4:45
It’s a natural process, but it runs more quickly here and sequesters large quantities of CO2. It’s all a question of the right ratio between pressure, temperature and depth. What I am holding here in my hand is two cores that show the before and after of the Carbfix method. One of them is the basaltic rock that you can see has a lot of holes in it. So, the water which we inject into the ground goes through these holes and the CO2 in the water dissolves metals
5:21
in the rock and forms a mineral called calcite. And this core that I’m holding here shows you the white dots is CO2 that has been turned into stone filling up the holes in the rock.
5:39
The CO2 can stay in the rock forever. Several hundred million tons of CO2 could be stored under this plant alone, and much more worldwide.
5:52
In principle, it's a brilliant process, says Thorben Amann. At the University of Hamburg, he's working on ideas to remove CO2 from the atmosphere.
6:04
But of course, you do have to ask yourself what it costs. And if there are other solutions that can make a contribution, which are perhaps less costly.
6:16
But direct air carbon capture is one way. There’s huge potential.
6:23
At least in places where there is enough basalt rock and green energy. But is it really the way to stop climate change? You cannot use this technology as an excuse for business as usual, it can only be an addition to all our other efforts in reducing emissions, reducing dependency on fossil fuels, changing over to greener sources of energy. We need to do all of those things. According to the UN intergovernmental Panel on Climate Change, carbon dioxide emissions need to be reduced quickly
7:01
and drastically to hold global warming to 1.5 degrees Celsius, as laid out in the 2015 Paris climate agreement. But to ensure this, existing greenhouse gases also have to be removed from the atmosphere. This is known as "negative emissions": The curve needs to fall below zero.
7:21
Currently just two gigatons of carbon dioxide are extracted from the atmosphere per year - mainly through reforestation. A tiny fraction is extracted using technical methods. According to one study, these would have to extract over 1,300 times more by the middle of the century than they do now.
7:43
As it is now, it won't work. It has to be done faster. If we facilitate more research, of course it will go faster. But it's not all we need. The right political guidelines are also necessary, to specify which direction we want to go in, which goals we want to have.
8:02
At home in his garden, Marcel Rensmann also relies on a small-scale technical solution putting up umbrellas to protect against the heat.
8:15
We have two umbrellas for the area where children play. At 30 degrees in the shade with direct sunlight - the garden faces south it's not very sensible to be there without shade.
8:29
Is the idea of a giant parasol to cool the whole planet a crazy one? Actually not, it’s been around for some time.
8:38
In 1991, the Pinatubo volcano erupted in the Philippines. Hundreds of people were killed, and the damage was enormous. Yet the volcano did something that researchers all over the world have been studying ever since.
8:54
The volcano ejected sulfur gas into the stratosphere, where it reacted with oxygen to form tiny particles. This formed a thin layer which reflected and blocked the sunlight, creating a kind of giant shield, like a parasol for the planet.
9:10
For months, temperatures were half a degree cooler than usual.
9:15
If volcanoes can do it, why can't humans? Special aircraft could bring the sulfur up into the stratosphere.
9:26
Technically, it is possible to create an artificial shield against the sun. The Max Planck Institute for Meteorology in Hamburg is researching how it could work.
9:36
Ulrike Niemeier and her team are using data collected during volcanic eruptions.
9:44
If we brought sulfur into the atmosphere, it would be globally distributed, in all directions, via air currents. It would affect everybody. This is exactly what makes it difficult to assess the impact and consequences.
9:57
We have to see what the impact of a sulfur emission up there would be, what kind of climate effect would it have. Maybe there would be side effects we can't easily foresee.
10:08
It could change rainy and dry seasons regionally, with consequences for farmers. It’s also not clear how much sulfur would be needed.
10:19
Sulfur has a lifetime of about one year, so that means you would have to bring up large amounts continuously, or at least once, twice, three times a year, to get to a fairly constant layer. If you stopped the whole thing, the sulfur would be gone again in two years at most, and the earth temperatures would rise rapidly again.
10:39
No one has yet dared to attempt such a technical intervention in the course of nature. But suitable aircraft could be available in just a few years.
10:50
It should really only be used as a last resort. But if we don't reduce emissions, I think life on Earth will become very difficult in some regions, which could very well tip the public mood in favor of such methods. Of course, this would mean creating another artificial solution on top of artificial climate change, which is not such a nice idea either.
11:15
Dr. Niemeier would then want to see a political framework put in place to regulate the deployment of sulfur worldwide.
11:24
The idea was sparked by a volcanic eruption. Volcanoes also happen to provide the raw materials for other solutions which could permanently remove CO2 from the atmosphere. Volcanic rock can be used as a greenhouse gas sink, not just in Icelandic soil.
11:46
In Ortenau, Baden-Württemberg, basalt rock dust is being spread across the fields.
11:58
It’s an experiment to show that CO2 can also be sequestered without specially developed high-tech machines.
12:10
What we are doing here is accelerating a natural process. The weathering of siliceous rock happens around the globe all the time.
12:19
In the weathering process, rainwater reacts with the minerals in the rock.
12:26
The CO2 becomes fixed and permanently bound within a salt, as a decomposition product. The conditions in the arable soil are ideal.
12:37
The plants that grow there, the microorganisms that live there, they produce CO2: The CO2 concentration in the soil is much higher than in the atmosphere. That accelerates the weathering process. It sounds simple enough, but it requires more research.
12:54
Farmer Georg Hosch is already struggling with one of the more surmountable problems on his first field: the machine is taking longer than expected.
13:04
This technology is actually designed for fertilizer - for lime that's why too little is coming out,
13:12
but we just improvise and double back.
13:18
There is less of the powdered rock, which is very fine and dry. It creates a lot of dust.
13:25
I think you can see the effect in the neighbor’s field, too
13:29
A debriefing with the scientists. The method and the formula still need some work.
13:36
Every field, and every kind of soil is different. The grain size makes a difference too.
13:43
The finer we grind the rock, the greater the surface area you can cover. There are pros and cons both ways. If you have very finely ground material, with very little moisture, you get a lot of dust when you distribute it.
13:57
The production of the material is also more expensive, which is why the researchers want to use existing powdered rock, if possible. It can be found by the ton, simply lying around in quarries. This would be cheaper and more efficient.
14:13
Another advantage is that enhanced weathering releases nutrients that improve the soil.
14:23
Thorben Amann's team at the University of Hamburg is investigating exactly how much CO2 is captured in the process.
14:31
The result: The method works, and not only in the laboratory.
14:37
It also works in the field; we have to assume that. It's just more difficult to prove it. Of course, a field is not enclosed like a bucket, or a tube, or a huge rain barrel used for an experiment. It’s open in all directions - upwards, downwards, to all sides so it’s hard to really trace where the products of our weathering ended up. Are they still stuck in the ground, maybe we can’t recognize them at first, will we spot them again later? That's the challenge.
15:06
Dr. Amann is sure it will work and could capture up to 5% of the CO2 emitted annually worldwide.
15:14
The infrastructure already exists, and there is plenty of arable land.
15:25
But there’s even more ocean. The oceans already absorb around a quarter of the carbon dioxide emitted, and researchers think the real figure might be much higher. The problem is that when CO2 dissolves in water it turns into acid, which harms both animals and plants.
15:45
The carbon dioxide would have to be permanently sequestered in the ocean, and acidity levels need to be reduced.
15:54
An experiment is currently being prepared at the Geomar Ocean Research Center in Kiel. Measuring probes are installed in these simple boxes, which are filled with soil and water. Sonja Geilert and her research team call these boxes ‘benthocosms’.
16:12
We have managed to bring the seabed to the fjord. By filling these benthocosms with sediment from the Baltic Sea and pouring fjord water over it, we can simulate the seabed of the Baltic Sea.
16:28
Geilert and her team have retrieved sediment from the seabed in various sea locations.
16:36
The experiments are now being done in the benthocosms, without any risk to the environment.
16:43
Rock dust will be added to the water soon, in different grain sizes and ratios.
16:52
It can be silicate, or carbonate minerals. When they dissolve, the marine chemistry; the chemistry of the seawater, is changed in a way that means more CO2 can be absorbed.
17:06
A welcome side effect is that it also neutralizes harmful acidity in the water. These processes can be precisely measured.
17:16
We have different probes that we insert into the sediment itself and some that we measure at the surface so we can determine exactly how the chemistry changes, and how the organisms and bacteria in the sediment are subsequently affected.
17:31
The seabed is teaming with life. Starfish, snails and worms could all be at risk from heavy metals that could be lurking in the rock dust.
17:43
Nickel and manganese for example can have a toxic effect on some organisms. But it has not yet been researched how much is released, and whether it really has a negative effect on organisms. That's exactly what we want to find out here.
17:57
The weather has taken a turn for the worse at the fjord in Kiel. Cold and rain are hampering the researchers’ work.
18:05
And this is the tricky part: the different mixtures have to be carefully distributed in the benthocosms.
18:17
We're sprinkling lime into the benthocosms. It’s actually a byproduct of cement production.
18:26
We want to get just the right mixture, so it all dissolves and there is no thick layer left at the bottom of the benthocosm.
18:36
A layer would also cover creatures on the seabed.
18:41
In a few months it’ll be possible to see exactly how well the process works. By then, results be will also be available from experiments conducted in other locations, such as the coast of Gran Canaria.
18:55
Creatures live just below the water surface there, too. The influence on them of minerals added to the water is also being tested in closed containers. The potential of this method could be huge.
19:13
You need large quantities, so also new ships, or part of the loading capacity of existing ships could be used for distributing the rock dust. But either way, we have to come up with a method to get the material into the ocean.
19:32
New methods, such as here on the Atlantic coast of Morocco. On the edge of the Sahara, this plant is already extracting CO2 from the atmosphere.
19:43
Marine algae do the job in the huge tanks.
19:49
Biologist Raffael Jovine came up with the idea.
19:54
Algae naturally absorb CO2 from the water and store it as carbon.
20:03
We learned very quickly how much light they need, how many nutrients they need, what temperature they need, how much wind they like, just what makes these algae happy, as it were, so they grow fast.
20:17
The organisms are also very generous. They've been around for hundreds of millions of years and they're very patient - they've put up with a lot of our research.
20:31
The algae in these cylinders in the greenhouse are just two weeks old, they are not robust enough for the outdoor tanks yet. Dr. Raffael Jovine and his team have been tinkering with it for eleven years.
20:48
The algae are indigenous to Morocco. They grow especially quickly under the facility’s conditions. Their biomass doubles in less than one day.
21:01
In this environment, they can be very effective, 30 times more effective than trees in extracting CO2 from the air.
21:10
The location on the Moroccan coast is ideal.
21:14
The algae like the local climate and lots of sun. The nutrient-rich water comes from the sea, and the electricity for the pumps and paddle wheels is from local wind and solar plants.
21:28
Harvesting takes place after 30 days. The algae are dried in machines, or in the sun. This is how they end up looking.
21:40
Here are our dried algae. They're now dehydrated, super dry and super salty. We can now bury these algae directly and they will last for several thousand years.
21:57
Buried in the desert soil, carbon dioxide can no longer escape.
22:03
The aim is for the algae plant to operate as quickly and energy-efficiently as possible.
22:11
Jovine and his team are already one step ahead.
22:20
In this experimental plant made of Plexiglas, sensors constantly measure the conditions and adjust them independently for optimal growth.
22:34
In this new greenhouse, we are trying out the technologies to automate our algae cultivation.
22:42
Algae can adapt very well to the environment, but we can also adapt the environment to the algae here in the greenhouse.
22:53
Construction of a plant ten times larger than this one is about to begin. Others are planned. Here in southern Morocco, 400,000 tons of CO2 could soon be removed annually. And that’s just the start.
23:09
In Morocco alone, there are 5,000 square kilometers of land that’s ideal. And that's just Morocco.
23:18
Worldwide, there are about half a million square kilometers of perfect land - flat, sunny, by the ocean.
23:27
About two billion tons of CO2 per year could be sequestered this way, about 5.5% of current emissions. Many companies are interested in the technology. By buying CO2 certificates, they could improve their carbon footprint.
23:46
The method wouldn’t work in the German climate. But another one does, which also relies on biomass from plants.
23:54
Helmut Gerber helped develop this pilot project in Dörth, Rhineland-Palatinate.
24:02
The raw materials are organic waste, in which plants have stored carbon naturally.
24:11
We use residual materials from wood chip production, which we obtain from the local forest. But we could use any other dry plant residues here to produce biochar.
24:22
Coal from plants has been around for centuries. But Gerber's machine processes the residues far more efficiently and cleanly.
24:33
In its latest version, it runs entirely on its own energy. No harmful gases are released.
24:41
In the end, the wood chips are turned into biochar.
24:49
We rediscovered methods that already existed, technology from old civilizations which was originally developed by Indigenous people in Brazil. We built a machine which can also be operated in central Europe,
25:03
which complies with the limits and also ensures that the heat generated can be used.
25:12
Here in Dörth, the energy is fed into the local heating grid. The system is already working and is finding new customers worldwide. The order books are full for Gerber and his team. The system being assembled here is soon to be installed in the USA.
25:33
Our buyers are composting plants, municipalities, cities that process green waste in the facility.
25:42
These days we also have industrial customers.
25:46
Our customer range is widening due to climate change being such a massive issue now.
25:53
Biochar is also produced in Dörth. We meet Marcel Rensmann again, who works as plant manager at Gerber. They take a sample of the biochar that permanently sequesters CO2 from the atmosphere.
26:10
Great quality. Try a piece?
26:13
You probably wouldn’t want to eat it! It’s mostly used as a dye, as an additive in concrete, and even in skin scrubs.
26:23
Or traditionally as a soil conditioner in agriculture. A look under the microscope shows why.
26:31
Biochar is a carrier in compost, it works like a sponge, it binds and stores nutrients and water, and since our summers are getting hotter and hotter and it's raining less and less, with extended periods of drought, the biochar is very helpful.
26:49
Marcel Rensmann also uses biochar at home in his garden. He mixes it with sand and humus before planting his vegetables in it.
27:01
It also helps on a small scale, he says.
27:05
In our kitchen garden, where we’ve added significantly more biochar, we don’t have to water as much. That’s one effect which is very clearly achievable.
27:16
In this way, his garden is also making a contribution to the fight against climate change, albeit a very small one.
27:24
Winning the battle against climate change cannot only be achieved by technical solutions.
27:33
Avoiding a ton of CO2 by not emitting it in the first place costs relatively little. Recapturing a ton of CO2 that is already in the atmosphere costs much more. So you have to think: do you want to do nothing and pay ten times as much, maybe twenty times as much?
27:50
Or would you rather save money and just do the obvious thing, by not emitting CO2 in the first place?
28:00
High-tech solutions are crucial to stop climate change. But even the best methods cannot win the battle alone.
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