字幕列表 影片播放 列印英文字幕 The oil company Equinor is doing something extraordinary on the Sleipner gas platform in the North Sea. It pumps millions of tons of carbon dioxide under the sea bed: The greenhouse gas that threatens to warm the planet is simply bunkered away. And Equinor has plans to sequester even more carbon dioxide. The storage potential in the North Sea is large enough to handle a substantial part if not everything that comes out of Europe. Can that work? Will ships with CO2 soon be going to Norway to sink our climate problem under the North Sea? The technologies exist, but do they really advance climate protection or are we just buying time? According to the Intergovernmental Panel on Climate Change, we can only emit a maximum of around 330 billion tons of CO2 if the rise in global temperature is to stay below 1.5 degrees Celsius. We are currently releasing around 42 billion tons a year. If we carry on as before, the CO2 budget would be used up in around 8 years, by 2028. Steps like closing coal-fired power plants, expanding the use of renewable energies and switching to electric cars will cause CO2 emissions to decrease. The more ambitious we are, the more they go down. But keeping the increase below 330 billion tons seems a hopeless cause. And it means there'll be more CO2 that has to be removed from the air. We need reforestation. We have to think about how to deal with our bogs, but that won't be enough. Even if we cut our CO2 emissions in half every decade, we will still have to remove several hundred million tons of CO2 from the atmosphere by the end of the century. So, we have to ask ourselves where we can put it. Norway has a lot of experience removing and storing CO2. Equinor extracts natural gas on a peninsula near Hammerfest, the northernmost city in Europe. Andreas Sandvik is in charge of the plant. He is proud that a way has been found here to get rid of CO2, but also to deliver an immense amount of fossil energy to Europe. It is amazing. It's a lot of energy. Typically energy for a city of 60,000 inhabitants for a whole year that's about 1.2 gigawatts. So it's amazing. CO2 is always a by-product of natural gas extraction. But the crucial thing here is that it flows back under the North Sea. The system is controlled remotely from the command center. There is no offshore platform. One pipeline brings natural gas to the plant, while another carries CO2 back under the sea. In this, the gas stream coming in, about 6% of the content is CO2. And this is quite unique about this plant, because we remove the CO2, we dry it and compress it and we push it back to a separate reservoir offshore for permanent storage. 90 tons an hour, almost 800,000 tons a year that we store permanently in this reservoir, offshore 143 kms out. The state-owned company that made Norway one of the richest countries on earth would like to benefit from this experience. Equinor is in the process of establishing a new business model — it calls the project Northern Lights. As early as 2023, the first ships will bring CO2 from European industry to Norway. A new pipeline descends steeply from the coast, then runs 110 kilometers along the sea floor, to a point where the greenhouse gases are injected 2,500 meters deep into the North Sea sediment. Sverre Overå is responsible for the new field of business. It's his job to lead the company into the future. Norway is seeing this as an opportunity here to actually continue to use the resources that are in the North Sea, not as an energy provider but as a storage provider for industrial CO2. Construction of the plants has started, and the first test drilling has been done. The gigantic Northern Lights project is meant to pave the way for the large-scale storage of CO2. Its initial goal is to free Europe's industries from greenhouse gases. If we succeed then we have the opportunity to actually help clean up quite a few of the industries that have no other option and we will allow these industries actually to stay here in Europe. It's hard to see a world without steel, it's hard to see a future without cement. They are essential and they need to decarbonize as well. Even if steel production switches to renewable energy sources, there will always be an amount of CO2 left over from the manufacturing process. Looking at German industry as a whole, this remaining CO2 accounts for around 7 percent of CO2 emissions. If Europe is serious about climate protection, these emissions must also be stopped. But is it realistic that freighters will bring CO2 from Germany to Norway? Today there are only four ships like the Froya worldwide. Tommy Pederson is responsible for loading the tanker. In the Norwegian port of Porsgrunn, it takes on CO2 that was released during the production of fertilizers. The gas is delivered to the food industry, which uses it in beer and fizzy drinks, for example, or for cooling. Today, CO2 is a commodity in small quantities. After the gas has been cooled and compressed, the Froya transports it in liquid form. The tank holds 1500 tons of CO2. Assuming that all of the carbon dioxide produced by German industry would be transported by ships like the Froya, around 100 of these tankers would have to travel from Germany to Norway every day. But that's not a problem for the specialist. In theory it will be just a cost calculation, how is the optimum size of the ship, from around the North Sea down into the northern sea seabed. I'm sure if this is a technology that those companies will chose, they will calculate the right size of the ship. So, shipping CO2 to Norway is plausible. But would those millions of tons of greenhouse gases really stay put under the ocean floor? This is the Kieshof Mire near Greifswald in eastern Germany. Prof. Hans Joosten has many objections to the idea of sinking our greenhouse gases using technical processes. He believes our priority should be to restore natural CO2 stores, such as bogs. We have to get away from the illusion that we can do business as usual and develop a technology that compensates for all our sins. Joosten is Dutch. He has researched bogs all over the world, works on the Intergovernmental Panel on Climate Change and is called "the peat pope“. Here Joosten tries to understand the origin and development of bogs in the meter-thick layers of peat. These are actually my favorite peat to taste. These water peat mosses. They taste very fine, often sulfurous. Sulfide-like. And of course we have to use all of our senses to better understand nature. We always think that we need a lot of devices to measure things, but we shouldn't forget that we can do an incredible amount with our eyes and ears, our noses and our mouths. There are hardly any idyllic places like this left in Germany: 99% of bogs have been drained and thus destroyed. This has made them climate killers - because all the peat that a bog like this stores is then gradually released into the atmosphere. That's pure stored carbon. Half of this plant matter consists of carbon and that is stored away. It then grows up layer by layer. With us in in the order of 1/2 mm to 1 mm per year. Over thousands of years these layers are meters thick and contain a great deal of carbon. That is pure climate protection. This only applies to intact bogs. Since almost all bogs in Germany have been drained, they give off a lot of greenhouse gases - almost 6% of total emissions. More than air traffic. We calculated that if we restore water to drained bogs, we will be able to compensate for even more than the warming caused by CO2 emissions since the industrial revolution. So bog re-wetting is a very important step — along with creating cooling systems for a world that is getting warmer anyway. That would be desirable. But how would it be possible to restore bogs to their natural state in an industrialized country like Germany? The largest oil and gas deposits in the North Sea are here, off the coast of Stavanger in Norway. The plans would mean pumping would continue here, but in the opposite direction, after those deposits are eventually exhausted. But would the CO2 from European industry really stay underground or would it become a time bomb? I think we can use the example that oil and gas is in the ground and it stays there until we try to take it out. And what we doing essentially is the reverse. We're placing CO2 in the ground. The headquarters of the Norwegian Petroleum Directorate is also here in Stavanger. It makes decisions on the resources under the North Sea, issues drilling licenses and inspects rock formations. Fridtijov Riis is a geologist who has long been searching in the drill core archive for the optimum sediment into which the first industrial carbon dioxide will be injected. We have been looking at possible storage options for many years. I think I started with this in 2006. And one of the first suggestions from our side was this Johanson formation because it's one of the good sandstones. I can touch it, feel it, I feel this is sand with a lot of pore space between the grains. Under the North Sea, the pores of the sandstone are filled with water. Most of the injected CO2 dissolves in it — turning it into sparkling water. The bigger the pores, the easier the gas can spread. You can test it with your own, just blowing it and see if you can get some air through it. This is quite good. I don't need to get too much force on my blow to get the air through. The Johanson Formation, which is intended to absorb the CO2, lies below the Troll Field: a gas deposit that contains another 30 years' supply of the fossil fuel. In between are several layers of dense shale rock. The Base of the Johanson formation is this red, somewhere in this area. Because of the gas production from the Troll field, the pressure is falling in these more shallow reservoirs, that means even if there should be a little bit of leakage of CO2 from this one, it cannot escape from the under pressure in the overlaying sands. So far everything has been going well with the storage of CO2 in Norway. At the Sleipner gas drilling platform, more than 1 million tons of CO2 have been pumped back underground every year for 25 years. The Northern Lights project aims to start with 1.5 million tons per year. If you look at the sheer magnitude of the problem globally there is a need for thousands of facilities and we're talking hundreds of millions of tons per year. That needs to be handled. Carbon capture and storage, or CCS, has also been researched in Germany. A 2017 experiment was a success. The CO2 remained in the ground under Ketzin, in eastern Germany, but it raised fears of earthquakes and escaping gases. Since then, the storage of CO2 has been politically dead in Germany. Even research is essentially prohibited. In Ketzin, where I was also deeply involved in the safety concept, I would have gladly built a house close to the storage facility at any time without any worries. I would have been worried if I'd put it in the wrong place in the wrong way with the wrong partner. For Frank Schilling it is clear that countries like Germany that emit a lot of CO2 also have to take responsibility for it. He says CCS is indispensable. There are estimates that in Europe we have enough storage space for 1000 years for our CO2 emissions. At the moment we have CCS as a good alternative. If someone has a better one in 30 years, all the better. But right now we have to improve the technology so that it is safe and also controlled safely. Hans Joosten's top priority when it comes to climate protection is to return the bogs to their natural state and thus stop their CO2 emissions. Here in the Recknitz region near Rostock on the eastern German coast he is researching how a re-wetted bog can become a CO2 store again in the long term. The Tribsee Bog was drained over the centuries. This allowed oxygen to penetrate the bog soil and break it down. That released a lot of carbon. It was re-flooded 20 years ago. During the period it was without water, it was a system in decline. We have calculated that we lost 2.7 meters of peat at this location over the last few decades. And now we are looking to see whether we can not only stop these processes, but also turn them around in order to get new peat formation at higher water levels. The scale of the problem is vast: Half of northern Germany has been drained to grow potatoes or corn, or to graze animals. Each hectare then emits as much CO2 in a single year - 29 tons - as a car does in a typical lifespan of 200,000 kilometers. In Hankhausen in the northwest, landscape ecologist Gerald Jurasinski is investigating what happens when a drained bog is flooded again. He discovered that at first it produces methane - another very dangerous greenhouse gas. But after a few years the methane emissions decrease and then the bog begins to store CO2 over the long term. We have just extrapolated that, for all areas that are currently drained globally. And you can see very clearly that the faster we return water to the bogs, the better it is for the climate. Drained bogs make up seven percent of arable land in Germany. Is it even possible to turn back time? If we take climate protection seriously, we have no alternative. When you understand that agriculture on bogs in Germany causes annual climate damage of 7.4 billion euros - which corresponds exactly to the total added value of the whole of agriculture - then you have to ask yourself: what are we doing here? Why is it that an activity that causes 7, 8, 9 thousand euros damage per hectare is allowed, and even subsidized. Because of course these greenhouse gases that are emitted must be compensated for somewhere else. Somebody else has to pay for it. It won't be easy to restructure agriculture and convince farmers to turn huge areas of farmland into wet bogs again. If we follow the Norwegians' plan for dealing with CO2, Europe will soon have lots of facilities like the Klemetsrud waste-to-energy plant near Oslo. Here CO2 is filtered from the flue gases. This could serve as a model for other industry sectors that have not yet been able to make their production carbon-neutral. Jannicke Bjerkås initiated the CCS project at the waste-to-energy plant in 2014. I'm proud and I believe that it's meaningful to work with it because this could actually make a difference. This is something we need do in order to basically save this world. Bjerkås wants to prove that it is possible to remove CO2 from industrial emissions. The waste-to-energy plant releases 400,000 tons of CO2 every year. The small pilot plant can only collect 1000 tons of it per year. But that shows that it can work. When it comes to the capture rates, the technology has proven to be extremely effective and we have managed to capture more than 95% of the CO2 from the pilot plants. When it comes to the energy use, it's quite energy demanding. That usually makes capturing CO2 very expensive. But that's not a problem here in the waste-to-energy plant. There is an abundance of waste heat here. The big challenge is to make capturing CO2 economical. Its share in the flue gases is only 5-10%. It is important to find the right chemicals that can bind and enrich the CO2. They are then removed with heat and used again. It's quite costly today because we are at the very beginning of the development. There are only a few plants operating to today and none of them are actually on industrial sources. The biggest challenges is, that today's economy is not favoring the handling of CO2. It is more attractive businesswise simply to emit the CO2. A high price for CO2 could make carbon capture and storage increasingly attractive. Since around half of the waste in this waste-to-energy plant consists of biomass, CO2 is even indirectly extracted from the air, because when this biomass grows, it absorbs CO2. If this is trapped during incineration and bunkered away, it reduces the concentration of greenhouse gases in the atmosphere. We go CO2 negative. And we know that we need to develop CO2 negative solutions in order to reach the Paris agreement. So waste to energy business can be very important in that matter. So, this is what the future of getting CO2 out of the atmosphere could look like. Joosten is in his favorite place - the Karrendorf meadows. Here you can see how peatlands grow in their natural, wet state. They don't release CO2, but instead absorb it. And yet they can still be used for agriculture - by growing reeds. A lot can be made out of these reeds: roofs, plastics, biogas. Reeds are an example of a plant that can be harvested sustainably without damaging the bog. There are already many ideas about what can be cultivated in bogs. In Hankhausen in western Germany, large areas of moss are being cultivated for the first time on a rewetted bog. After all, mosses are the natural vegetation on peat bogs. Can they be grown and harvested like any other field crop? The search for the best mosses for agricultural cultivation is underway on the edge of the trial area. Anja Prager and her team grow mosses from all over the world here. They aim to find the ones that grow as well and as quickly as possible. In this way they also absorb CO2 and turn the bogs into sinks for greenhouse gases. However, it will take more for mosses to become a profitable product. Direct payments, supports and subsidies for farmers are not yet established. It's all a very new idea. We hope that we can show, here on the demonstration farm, that this is actually feasible as well as what we can harvest. Large-scale implementation really depends on political will, on further technological development - and on our finding the supermoss. Moss for what? As a replacement for white peat. Peat was once made from moss and horticulture needs huge amounts of it. So much that Germany's drained bogs are not enough and most of the peat is imported from the Baltic states. In about 15 years the German peat will be completely exploited. Then an alternative will have to be found. Mosses as a peat substitute would be a double benefit for the climate: No more emissions from peat extraction and the mosses bind CO2 from the air. All methods of binding CO2 must be researched - without prejudice. Time is running out.
B1 中級 美國腔 天然氣(Norway and CO2 emissions | DW Documentary) 10 1 joey joey 發佈於 2021 年 09 月 26 日 更多分享 分享 收藏 回報 影片單字