• Hanns J. Neubert und Ludger Wess

Herculean task.

Print Friendly, PDF & Email

32 KlimaHerkules Aufmacher

In the chart above, only CO2 emissions from the fossil fuels coal, oil and gas are listed. If other sources such as cement production or cattle breeding were also taken into account, they would be around ten percent higher. Source: BP

Stop climate change. Climate change is a global problem - and can therefore only be solved internationally. Strategies that rely on national solo efforts, on renunciation and bans will not work. What is needed are entrepreneurial initiatives and innovative processes that make it possible all over the world to remove CO2 from the atmosphere or convert it into other raw materials.

It's a Herculean task. In order to limit global warming to a maximum of 1.5 degrees Celsius, global emissions of carbon dioxide (CO2) must not exceed 55 percent of 2010 emissions according to calculations by experts at the Intergovernmental Panel on Climate Change (IPCC) in 2030. By 2050, additional emissions will have to be eliminated once and for all.

The recently published "Statistical Review of World Energy" by the oil multinational BP shows how difficult this will be. After all, CO2 emissions will not fall. It is not even stagnating. It is rising (chart on the right). According to BP, the total amount of fossil CO2 emissions rose to just under 34 gigatonnes in 2018. The 2.0 percent increase compared to 2017 was the highest in seven years.

A decline can only be observed in Europe and South America. In Asia, Africa and the Middle East, emissions continue to rise unchecked in line with economic development. There is still no answer to the most important question: How can these countries continue to catch up economically with the industrial nations and still reduce their emissions?

After a few years of decline, the USA recorded the largest increase in 30 years with a plus of 3.5 percent. BP blames this on the unusual weather conditions in 2018, both in terms of cold and heat. In the USA, the number of days that had to be heated or cooled was the highest in 50 years.

Despite the Paris Climate Treaty, nothing continues to happen worldwide. And that already has consequences today. As the IPCC's special report on the feasibility of limiting global warming to a maximum of 1.5 degrees emphasizes, the Earth is currently on a direct path to a plus-three-degree world. The report clearly shows that science has miscalculated its models: they were too optimistic. Climate change is progressing even faster than climate experts had expected in the IPCC status report for the 2015 Parish Conference.

In the Arctic, for example, the air is warming two to three times faster than the global average. This not only changes the global wind systems, causing heat waves and heavy rainfall in Europe. Worse still, the ice that previously reflected solar heat is melting dramatically fast. The dark sea surface is thus exposed and absorbs the warming rays of the sun. As a result, the sweet melt water could stop the salty circulation of the Gulf Stream far to the south, which ironically could lead to an ice age in Europe. At the same time, permafrost thaws faster than expected and releases the particularly harmful greenhouse gas methane (see box on page 34).

"The climate change problem is more global, it is more long-term, it is more uncertain and ultimately more irreversible than any other social problem I know," stated climate economist Gernot Wagner a year ago on Austrian Broadcasting ORF. But the way politicians, in particular, imagine solutions for the future of the earth, does not work - or no longer works.

In Germany, renunciations and bans are the main topics of discussion. This may work on a national level. But to reduce CO2 emissions worldwide by avoiding the burning of fossil fuels such as coal, gas and oil is not very realistic. It is difficult to impose renunciations and bans on a global scale because it would massively curtail the economic development opportunities of many countries. Would the industrialised countries really be prepared to pay the corresponding high financial compensation?

Humanity's hope is therefore in technologies that can be implemented worldwide that remove carbon dioxide from the atmosphere and shut it down. Or convert the CO2 produced by numerous industrial processes into usable raw materials.

But this is not easy either. Because these technologies are very energy-intensive. Thermodynamics teaches us that exactly the same amount that is produced during the combustion of fossil fuels must be added to the process energy in order to convert CO2 into other substances. It is therefore crucial to use catalysts and renewable energies in these processes.

The private wealth authors Hanns J. Neubert and Ludger Wess have set out on a search for corresponding ideas.

32 Klima 2

Eliminate CO2.

Innovation and tradition. The world needs both: innovation through new efficient processes to extract CO2 from the atmosphere. And traditional CO2 storage systems such as forests and the use of wood.

// 01 The CO2 catchers.

"In principle, the CO2 problem is like pouring water into a barrel every day without knowing when it will overflow. Now we are making a tremendous effort to put a little less into the keg than last year. I have always wondered why we don't try to draw water from the barrel," explains Christoph Gebald, co-founder of the Swiss company Climeworks (private wealth reported on the innovative company for the first time in December 2017).

The direct removal of CO2 from the ambient air is the most obvious solution to the climate problem. However, there are currently only two companies worldwide that use Direct Air Capture (DAC) in addition to Climeworks - Global Thermostat in New York and Carbon Engineering in Vancouver.

Two challenges have to be overcome during implementation. Firstly, the technology requires a great deal of energy. And secondly, the separated greenhouse gas must be stored in such a way that it never returns to the atmosphere.

Climeworks, founded in 2009, has developed a particularly elegant and forward-looking solution for both: It extracts the necessary energy from volcanic soil and transforms the captured CO2 into rock.

After Climeworks presented its first commercial "air vacuum cleaner" in Hinwil near Zurich in spring 2017, which can wash 900 tons of CO2 a year out of the air, it installed a smaller plant a few months later on Iceland directly next to the Hellisheiði geothermal power plant. The power plant pumps plenty of hot water from the Hengill volcano system southeast of Reykjavik and thus generates 300 megawatts of electrical energy.

Huge Climeworks fan boxes now suck in ambient air. Special filters bind the CO2 chemically. Once the filters are saturated, they are heated to around 100 degrees, which releases the gas from the filter again. It is then pumped with the return water from the geothermal power plant to a depth of 700 metres. A chemical process begins there in which the CO2 reacts with the volcanic rock and in less than two years turns into white calcite - it is thus removed from the atmosphere for an eternity.

At present, the small plant only produces 50 tons of CO2 per year, but in the final stages 2500 tons of CO2 per year are to become stone. Gebald and his partner Jan Wurzbacher assume that their technology could be used at numerous similar locations all over the world on volcanic ground.

At present, however, the removal of one tonne of CO2 in this way still costs between 600 and 800 US dollars. In three to four years, it should be only 200. In the longer term, Gebald is convinced, however, that the price could be reduced to 100 US dollars. This would put the company in an area in which its process could be financed at a corresponding CO2 price.

However, this example also shows how unhelpful the price path for one tonne of CO2 proposed in the German government's climate package is. The target price of 60 dollars by 2030, as announced there, does not give this fascinating technology a chance. 

Therefore Climeworks turns today additionally to farsighted humans, who would like to take over responsibility for their own climatic footprint. In its online shop, the company offers to convert 25 tons of pure CO2 into stone in the Icelandic underground for an annual investment of currently 24000 euros. To the comparison: An average German emits in this time approximately twelve tons.

____________________________

Climate gases - much more than just CO2.

CO2 accounts for 66 percent of global warming. In addition, there are other gases that contribute significantly to global warming. Methane is the second most important substance. It is 28 to 85 times more harmful to the climate than CO2 and contributes 17 percent to global warming. Man-controllable sources of methane are primarily rice cultivation and cattle breeding. In addition, methane is released from bogs and wetlands, increasingly in Arctic latitudes where permafrost thaws because warming is two to three times faster here than on the rest of the world.

Nitrous oxide is also increasingly becoming a problem. Much of this comes from natural sources. But modern agriculture, with its exaggerated fertilization and slurry from livestock farming, has pushed nitrous oxide concentrations even higher.

Although only extremely low concentrations are present in the air, technical substances from the earth also heat up. Tetrafluoroethane from cooling plants is 1300 to 3700 times more climate-effective than CO2, fluorocarbons even 10800 to 12400 times. Nitrogen trifluoride from the manufacture of solar cells and liquid crystal displays is even 12800 to 16100 times more problematic for the climate than CO2.

The worst greenhouse gas, however, is probably sulphur hexafluoride, which is used as a protective gas in the production of magnesium and escapes from leaks in gas-insulated high-voltage switchgear. It is 17500 to 23500 times more climate-effective than CO2. In order for the future climate to remain bearable for human civilization, the additional emissions of all these substances would actually have to be finally completed by 2050.

____________________________

// 02. Carbon sequestration.

A second possibility, which could contribute to the removal of CO2 from the air, would be to accelerate the weathering of rocks. For billions of years, this natural process has helped to bind the greenhouse gas. When stones chemically weather, carbonic acid is formed from the CO2 of the atmosphere in the surrounding groundwater. Positively charged elements, such as calcium or magnesium, retain the negatively charged carbonic acid in the groundwater, which then eventually reaches the oceans with the bound carbon. It remains there for thousands of years.

ArbeiterKarre.jpg

This process could be supported by large areas of natural stone gravel. Carbon could also be ploughed into fields, where it could even store nutrients. Researchers at the Potsdam Institute for Climate Impact Research calculated that there would be enough space on earth to allow one billion tons of carbon to disappear every year. By way of comparison, humanity releases eight billion tonnes of pure carbon every year. 

Because very large areas of land have to be acquired through lengthy negotiations or farmers have to be persuaded to use the gravel in their fields, no investors have yet found a way to invest in this method. Only the Leverhulme Centre for Climate Change Mitigation in Sheffield tries it on large agricultural areas in the USA, Australia and Malaysia. The US start-up investor "Y-Combinator" has recently launched a financing programme to promote young entrepreneurs who can submit business plans on the basis of this method. So far without success.

// 03. More forest.

The simplest method of binding CO2 is the afforestation of forests. Trees, especially fast-growing ones such as birches or poplars, store enormous amounts of carbon. The CO2 would then remain there for the next 100 to 150 years.

If the wood from old trees is used for building, the carbon would be removed from the atmosphere as long as the buildings remain standing. Wood could replace concrete, which is particularly harmful to the climate, because cement production releases huge amounts of CO2.

Factory, office and apartment buildings made of wood are a tradition in Canada and Scandinavia. In Baden-Württemberg, the proportion of new wooden residential buildings in 2018 was almost 30 percent, and for office and industrial buildings the proportion of wooden buildings in Schleswig-Holstein was 23 percent. Even high-rise buildings are possible. The highest in the world was completed in March this year in Brumunddal, Norway, 100 kilometres north of Oslo. Its 18 floors reach a height of 85 meters. The "HoHo" wooden tower built in Vienna by Austrian real estate investor Günter Kerbler is only one meter lower.

Wood could even be burned to generate energy if the CO2 released is separated and stored in underground caverns. The remaining charcoal could be used to loosen arable soils, where the carbon would then also remain for a long time.

Such processes, which are basically suitable for generating energy from all vegetable fuels, are called BECCS, bioenergy with CO2 capture and storage. Around half a dozen power plants worldwide operate according to this principle.

The challenge: BECCS can only be implemented on a large scale and therefore quickly comes into conflict with food production. For fear of resistance from landowners and the population, hardly anyone today dares to build even more such plants.

The biggest problem, however, concerns the forest itself. Unfortunately, the existing forests are in a bad position and it is unclear how they will respond to the progressive warming.

This year and last year, thousands of square kilometres of forest in Siberia, northern Canada and Brazil were set on fire by extreme drought. According to calculations by physicist Mark Parrington of the European Copernicus Atmosphere Monitoring Service in England, the fires around the Arctic alone have released an estimated 140 million tonnes of CO2, according to taz. Climate change is heating fires, and fires are heating climate change.

China is currently taking a positive stand when it comes to reforestation. Its "Green Wall" runs for 4500 kilometers parallel to the historic Great Wall of China, is several hundred kilometers wide and consists mainly of mixed forest. Over 60 billion trees have been planted since 1978. Originally it was planned as a barrier against desert winds from the north. When the "Wall" is finished in 2030, the forest will cover an area the size of Germany.

In addition, every inhabitant in China between the ages of eleven and 16 was obliged to plant three to five trees a year.

Other countries are also increasingly reafforesting. "A major problem with state-financed programmes, however, are the short political cycles. These cannot be used for long-term planning," criticises Peter Elsasser of the Thünen Institute for International Forestry and Forest Economics in Hamburg-Bergedorf.

Mangrove forests on the coasts have proven to be particularly effective CO2 reservoirs, as Monika Breuch-Moritz, Deputy Chairwoman of the International Oceanographic Commission (IOC) of UNESCO, explained in a lecture: "Although mangrove forests cover only two percent of the earth's surface, they store as much CO2 in their roots and soil as all terrestrial ecosystems put together. The destruction of mangroves is therefore much worse than a tropical forest fire.

In the meantime there are even funds for sustainable forest investments, which are intended as compensation for the oversized climatic footprints of especially wealthier people. However, it is important to take a close look - what do these institutes actually do? Where do they invest? And do they have certificates from reputable organisations?

An alternative is their own forest. "If I could choose to buy a forest locally and let it grow for climate protection reasons, or support a fund, I would always prefer the first option. Simply because then I have a more direct influence," says forest researcher Elsasser.

But reforestation can only be part of a whole package of measures. If 200 billion tons of CO2, a third of the carbon dioxide that has been released into the atmosphere since industrialization, were to be removed from the air with additional afforestation alone, Sweden would have to double its surface area, as Jean-François Bastin of the Swiss Federal Institute of Technology ETH in Zurich and his colleagues recently calculated. At the same time, the agricultural area must be increased in order to feed a growing world population, so conflicts are inevitable.  ®

Author: Hanns-J. Neubert

32 Klima 3

Convert CO2.

The incredible story of Clostridium autoethanogenum. Modern biotechnology can make significant contributions to returning the CO2 produced by industrial processes back into the cycle. Politicians only have to create the framework conditions for this.

Actually, the process is nothing new. Carbon monoxide has long been used in chemistry to produce ethanol as a fuel. "But we can do it better and cheaper. Because we have an important employee - Clostridium autoethanogenum," explains Sean Simpson, founder of the technology company Lanzatech.

In synthesis gas fermentation, organisms produce chemicals from a mixture of carbon monoxide (CO) and hydrogen (H2) as well as other gases, known as synthesis gas. These can be used as biofuels or platform chemicals in the chemical industry: Methane, ethanol, butanol, acetic acid and butyric acid.

Although microorganisms are not as productive as chemical processes, they require less pressure and heat and can cope with different ratios of carbon monoxide and hydrogen.

Particularly fascinating: If sufficient hydrogen is available, Clostridium autoethanogenum can utilize not only CO but also CO2. At high carbon dioxide concentrations, it is even able to produce hydrogen itself in a biological process.

The disadvantage is that the fermentation broth in which the bacteria do their work can only absorb limited amounts of gas. In addition, the ethanol produced is toxic to the bacteria in higher concentrations. And the product has to be separated by distillation - another energy-intensive step.

Lanzatech has therefore optimised its bacteria accordingly and is now using strains that can handle much higher alcohol concentrations. However, the bacteria cannot tolerate the presence of oxygen. It therefore finds ideal living conditions in the oxygen-free exhaust gases from steel mills. If other sources - waste, biomass or waste gases from refineries - are to be used, the oxygen must be completely removed beforehand.

Lanzatech was founded in New Zealand in 2005 by the two scientists Sean Simpson and Richard Forster. Both had previously worked for a company that wanted to convert biomass to ethanol. However, this was not possible. But the idea of using biotechnology to make industrial processes more sustainable did not leave the scientists alone. They searched the literature for suitable processes and finally concentrated on the utilisation of exhaust gases from large factories. They obtained the bacterium from a German collection.

In the following months, Lanzatech began as a real garage company - with a makeshift laboratory, borrowed money, discarded laboratory equipment and a refrigerator converted into an incubator from an abandoned supermarket branch. It quickly turned out that Simpson and Forster had hit the bull's eye with their idea. As early as 2006, they received funding, a real laboratory and, shortly afterwards, substantial financial resources.

"Nevertheless, it wasn't a walk in the park," says Frey Burton, who is responsible for sustainability issues at Lanzatech. "Something like this works well in the laboratory. The problem is process development so that the whole thing works reliably on a large scale. Our system is now running in a steel factory in China. The plant was commissioned there in May 2018 and has already produced 36 million liters of ethanol from the exhaust gases since then."

The production capacity is 72 million liters per year. A further ethanol-producing factory is currently under construction at the site of a steelworks in Ghent, Belgium. In India, the company plans to build three plants in which the bacteria will utilize the exhaust gases from oil refineries. A factory planned in South Africa will work with exhaust gases from an aluminium smelter and a Californian pilot plant will use biomass from agriculture.

Lanzatech does not only want to earn money with the production of ethanol, but also relies on a licensing model. The company benefits from the versatility of Clostridium autoethanogenum. "We can quickly convert our strains to produce other things, such as acetone," explains Burton. "In this way we can supply customers with tailor-made bacteria to produce the desired product from synthesis gas.

Lanzatech is not the only company that uses microorganisms to convert carbon oxides into valuable raw materials. "Living organisms are unbeatable in their ability to efficiently form very complex carbon compounds with dozens of carbon atoms from the raw material CO2 - provided they receive sufficient energy," explains Jürgen Eck, CEO of the German biotechnology company Brain AG.

The company, which was founded in 1993 and has been listed on the stock exchange since 2016, began working on a corresponding project almost a decade ago. The goal is to use bacteria to convert carbon oxides from the flue gas of lignite-fired power plants into useful substances. "We had found bacterial communities in the six-meter-wide flue gas channels of lignite-fired power plants that utilized the gases carbon monoxide and carbon dioxide contained in them," says Eck. "These bacteria, which occur in nature in sulphuric acid sources containing CO2, had settled there because the environment in the exhaust gases from the power plants is very similar to their natural habitat.

The project made good progress, but then fell victim to RWE's corporate restructuring. This is why Brain teamed up with Südzucker subsidiary CropEnergies AG - a company that produces bioethanol from sugar.

"In this process, which also works in the presence of oxygen, each molecule of glucose produces two molecules of ethanol and two molecules of carbon dioxide. We want to avoid its release," explains Eck. His idea: "We feed the greenhouse gas to organisms that produce dicarboxylic acids from it. These are the basic materials for plastics such as polyamides and polyesters. However, they can also be converted into more complex compounds by other microorganisms in a second step. They need hydrogen as an energy source".

This hydrogen comes from the electrolysis of water, a very energy-intensive process. What at first glance appears to be a problem could be the solution to one of the major challenges for the production of regenerative energy from wind and sunlight in Germany. At present, the amount of electricity generated from these sources fluctuates extremely. In some weather conditions with a lot of wind and sun, a multiple of the required electricity is produced. The electricity producers then have to pay Germany's neighbouring countries a lot of money to reduce their capacities and feed German surplus electricity into the grid. "Instead, we could use this electricity to produce hydrogen," Eck explains. "Hydrogen has a very high energy density and is relatively easy to store and transport. That's a very promising energy carrier for the future."

Then the overall balance would be excellent: electricity, which generates no CO2, is used to convert CO2 generated during fuel production into complex, industrially usable substances and thus prevent its release.

The potential of both technologies is enormous. "Germany is an extremely resource-poor country. But RWE produces 160 million tons of CO2 per year in North Rhine-Westphalia alone. It contains just over 70 million tonnes of carbon - roughly the same amount as Germany imports in the form of crude oil each year." The more of this would be processed with the help of bacteria, the better it would be for the climate.

"We see a future in which, for example, a steelworks would produce lightweight steel for aircraft parts, using our bacteria to produce not only fuel but also synthetic fibres, plastics and elastomers for the equipment and cabin of the aircraft," says Frey Burton of Lanzatech. "That would be real recycling management: waste avoidance, efficient use of resources and added value through CO2 reduction.

According to Lanzatech's calculations, if the principle were to be used wherever industrial production of CO2 takes place, 30 percent of the crude oil currently consumed could be replaced per year and global CO2 emissions reduced by ten percent.

However, the framework conditions must be right. "The CO2 price is important," Eck points out, "if CO2 production becomes more expensive, this can speed up the process enormously. If the price for a ton of CO2 were not 25 euros, as is currently the case, but 60 or 80 euros, this would probably generate a surge in demand. "We currently have the technologies, but not the framework conditions that would make them economically lucrative," says Eck.

Here, too, it becomes apparent how problematic the CO2 price of 60 dollars by 2030, as envisaged in the German government's climate package, is. The technology already available today for the conversion of CO2 would probably not have an effect on a large scale for another ten years. Much too late.

_____________________________

Forest against agriculture? The solution is more harvest on less land.

An efficient and simple way to reduce CO2 emissions is to reforest large areas. However, this conflicts with the need to feed a growing world population.

Contrary to popular belief, the solution to the food problem is not organic farming. Its renunciation of mineral fertilizers and efficient crop protection leads to a significant reduction in productivity. Organic farmers sometimes harvest less than half of what conventional farmers produce on the same land from cereals and potatoes. This is because all food crops today are more nutritious than their natural ancestors, but also poorer in poorly digestible constituents and insect-repellent bitter substances. Parasites also benefit from these improvements that breeders have made over thousands of years. If we do not use efficient antidotes, a large part of the harvest falls victim to them. The unpleasant truth: If humanity is to be fed 100 percent by organic farming, we would need a second planet.

It is interesting to note that modern biology could solve the problem. Plants with built-in resistance to pests and diseases have now been developed. These plants are controversial because they are genetically modified. On closer inspection, however, the associated fears prove to be unjustified.

Insect-resistant plants have long been found in nature. For example, they produce the toxin of the soil bacterium Bacillus thuringiensis (abbreviated Bt), which harms insect larvae when they ingest it. These bacteria can be found on every lettuce, every carrot, every potato and are routinely sprayed on plants in organic farming.

However, the natural soil bacterium has disadvantages: It harms useful insects, is washed away by rain, deactivated by sunlight - and must therefore be sprayed on several times. The so-called Bt plants, in whose genome the gene for the formation of the bacterial toxin has been incorporated, only damage insects that actually eat from the plant. It is harmless for humans because it would only be problematic if it were to enter an alkaline intestinal environment unharmed. But only insects have alkaline intestines; higher animals and humans have a strongly acidic digestive tract in which the protein is immediately broken down.

Bt plants have been cultivated for decades, especially outside Europe, and have significantly reduced the use of insecticides in the countries where they are cultivated. The results show that better harvests are possible without the use of synthetic insecticides.

The same applies to fungal infections - potatoes that have been made biotechnologically resistant to fungal attack no longer need to be treated. Organic agriculture, on the other hand, has to apply copper salts to combat this dreaded plant disease. These copper salts are not very efficient but poison the soil and water in the long term.

But biotechnology has even more up its sleeve. For some crops, a naturally occurring innovation could increase yields by 50 percent.

When green plants conquered the planet many millions of years ago, the oxygen content of the atmosphere rose dramatically and the CO2 content dropped. After all, the carbon dioxide content became so low that the plants had difficulty finding enough of it for photosynthesis. This deficiency led to an evolutionary adaptation.

Originally, all plants introduce CO2 into their metabolism through the formation of a molecule with three carbon atoms. However, this reaction is surprisingly slow, error-prone and often comes to a standstill. Above all, it only works efficiently enough when the CO2 concentration is sufficiently high. Some plants have therefore developed a mechanism in which CO2 is captured in an upstream step by the formation of a molecule with four carbon atoms.

These molecules then migrate to where CO2 assimilation normally takes place. At this point, the C4 molecule releases carbon dioxide and thus ensures that there is always slightly more carbon dioxide at the site of the C3 process than in the surrounding atmosphere. Plants that have undergone this adaptation are therefore called C4 plants.

The astonishing thing about this is that this completely natural, evolutionary development has already taken place more than 60 times in parallel and completely independently of each other in different plant lines. This is a clear indication that only minor genetic alterations are required to create this metabolic pathway.

Examples of C4 crops are maize, sugar cane and millet. An international team - supported by the Bill & Melinda Gates Foundation - is currently working together with the International Rice Research Institute IRRI to turn rice into a C4 plant. After all, rice is one of mankind's most important crops. The researchers assume that such a conversion can increase yields by up to 50 percent.

Another side effect: C4 plants require less water and nitrogen. This could drastically reduce the area under cultivation without increasing the need for mineral fertilizers. Once the trick has succeeded, it might also be possible to modify other C3 crops into C4 variants - wheat, rye, oats and potatoes. It would be a dramatic change in food cultivation. And the chance to free up more land for reforestation.

_____________________________

®

Author: Dr. Ludger Wess

Publishing address

  • Private Wealth GmbH & Co. KG
    Montenstrasse 9 - 80639 München
  • +49 (0) 89 2554 3917
  • +49 (0) 89 2554 2971
  • This email address is being protected from spambots. You need JavaScript enabled to view it.

Languages

Social media