Tag Archives: carbon storage

Far less carbon capture is needed to avoid a climate catastrophe, study argues

Tackling climate change means drastically reducing the world’s emissions. To do so we not only have to change our economy and society but also consider the use of carbon mitigation technology, specifically what’s known as carbon capture and storage (CCS).

Credit Flickr

CCS essentially means trapping carbon dioxide (CO2) at its emission source, such as a coal plant, and then storing it underground to keep it from entering the atmosphere. It’s an expensive process and there’s more than one way to do it.

The Intergovernmental Panel of Climate Change (IPCC), which groups the world’s leading climate experts, has included CCS on its checklist to keep global warming to less than 2ºC, as included in the Paris Agreement.

Almost four times less carbon has to be captured than previously thought in order to meet climate targets

A new study by Imperial College London said that no more than 2,700 gigatons (Gt) of CO2 would have to be captured to meet the most aggressive climate targets. This is much less than the previous estimates by academics and industry groups, which have suggested the need to capture more than 10,000 Gt of CO2.

The study also argued that the current rate of growth in the installed capacity of CCS is on track to meet climate targets. But research and commercial efforts should focus on maintaining this growth while identifying enough underground space to store this much CO2.

Until now, the amount of storage needed hadn’t been specifically quantified. To do so, the team combined data on the past 20 years of growth in CCS, information on historical rates of growth in energy infrastructure, and models commonly used to monitor the depletion of natural resources.

There has been an 8.6% growth in the CCS capacity over the past 20 years, according to the study led by Dr. Christopher Zahasky. This means that the world is now on a trajectory to meet many climate change mitigation scenarios that include CCS as part of the mix.

“Even the most ambitious scenarios are unlikely to need more than 2,700 Gt of CO2 storage resource globally, much less than the 10,000 Gt of storage resource that leading reports suggested. If climate change targets are not met by 2100, it won’t be for a lack of carbon capture and storage space,” Zahasky said in a statement.

The researchers said that the rate at which CO2 is stored is important in its success in reducing greenhouse gas emissions. The faster CO2 is stored, the less total subsurface storage resource is needed. This is because it becomes harder to find new reservoirs or make further use of existing reservoirs as they become full.

That’s why the researchers argued in the study that storing faster and sooner than current deployment might be needed to help governments meet the most ambitious climate change mitigation scenarios.

“Our analysis shows good news for CCS if we keep up with this trajectory—but there are many other factors in mitigating climate change and its catastrophic effects, like using cleaner energy and transport as well as significantly increasing the efficiency of energy use,” said co-author Samuel Krevor.

The study was published in the journal Energy & Environmental Science.

“Algae forestry” could take CO2 straight out of the air and put it on your plate

Through a mixture of algae, eucalyptus, carbon storage and bioenergy, researchers believe they have found the recipe to simultaneously provide food in many parts of the world while taking out CO2 from the atmosphere.

As the world struggles to keep global warming at manageable levels, scientists are exploring several avenues to reduce emissions. Researchers from Cornell University, Duke University, and the University of Hawaii at Hilo have an idea that could prove extremely effective: they devised a system that can act as a carbon dioxide sink while also generating food and electricity.

They integrated algae production with carbon capture, in a system they call ABECCS (algae bioenergy carbon capture and storage). Researchers have already set up a 7,000-acre ABECCS facility that can yield as much protein as soybeans produced on the same land footprint, while simultaneously generating 17 million kilowatt hours of electricity and sequestering 30,000 tons of carbon dioxide per year. A portion of the captured COis used for growing algae and the remainder is sequestered. Biomass combustion supplies CO2, heat, and electricity, thus increasing the range of sites suitable for algae cultivation.

“Algae may be the key to unlocking an important negative-emissions technology to combat climate change,” said Charles Greene, Cornell professor of Earth and Atmospheric Sciences and a co-author of new research published in Earth’s Future, by the American Geophysical Union.

“Combining two technologies — bio-energy with carbon capture and storage, and microalgae production — may seem like an odd couple, but it could provide enough scientific synergy to help solve world hunger and at the same time reduce the level of greenhouse gases that are changing our climate system,” Greene said.

Often times, when an idea sounds too good to be true, it is. In this case, the entire project hinges on the economic viability of the algae. Researchers describe two scenarios in which financial viability is achieved:

  • when algal biomass can be sold for $1,400/t (as fishmeal replacement), with a $68/t carbon credit; and
  • algal biomass sold for $600/t (soymeal replacement) with a $278/t carbon credit.

Clearly, the price of algal biomass is essential, but an economy that supports carbon credits is also required.

There’s another issue with this type of project: In the ABECCS system, soy cropland is replaced by eucalyptus forests used for carbon storage that provides marine algae with CO2, heat, and electricity. While this can work extremely well on a small scale, on a large scale, the arable land and freshwater requirements for ABECCS could be unviable and cause competition with food production.

ABECCS won’t solve all our climate change woes, but it could be a significant puzzle piece.

Journal Reference: Colin M. Beal, Ian Archibald, Mark E. Huntley, Charles H. Greene, Zackary I. Johnson. Integrating Algae with Bioenergy Carbon Capture and Storage (ABECCS) Increases Sustainability. Earth’s Future, 2018; DOI: 10.1002/2017EF000704

Scientists turn CO2 into rock in Iceland

An international team of scientists documented a potentially viable way to remove anthropogenic (caused or influenced by humans) carbon emissions from the atmosphere: by turning into rock.

Air photograph of Reykjavik Energy’s Hellisheidi geothermal power plant. Credit: Árni Sæberg

No matter how much you talk and spin it around, the problem with global warming bounds down to one thing: we’re outputting too much greenhouse gas into the atmosphere, especially carbon dioxide (CO2). But what if we could somehow cheat, and trap that CO2 and lock it away somewhere where it wouldn’t do any damage? That’s what many teams believe is a key point of mitigating climate change, and that’s exactly what scientists working in Iceland have done.

The CO2 interacts with the surrounding rock, forming environmentally benign minerals. The entire process is quite fast, and it could perhaps be scaled.

Carbon Capture and Storage (CCS) is a field of science where CO2 is extracted from the atmosphere and stored underground. Geologists have mostly focused on existing voids, such as former oil fields, but that’s tricky because the fields are susceptible to leakage. So instead, they’re now turning to mineralizations – turning CO2 into minerals. Until now, this process was thought of as unpractical because it takes too long to solidify the CO2, but researchers from Columbia University, University of Iceland, University of Toulouse and Reykjavik Energy have found a way to make it work in two years.

Lead author Dr Juerg Matter, Associate Professor in Geoengineering at the University of Southampton, says:

“Our results show that between 95 and 98 per cent of the injected CO2 was mineralised over the period of less than two years, which is amazingly fast.”

They key is basalt – a volcanic rock which Iceland has an abundance of. The whole Iceland is made up of basalt (90%), and the rock is also rich in calcium, magnesium in iron – key elements for carbon mineralization. The process is straightforward: CO2 is dissolved in water and carried down the well. When it comes into contact with the rocks, it reacts and starts forming carbonate minerals. After two years, the carbon is completely trapped.

“Carbonate minerals do not leak out of the ground, thus our newly developed method results in permanent and environmentally friendly storage of CO2 emissions,” says Dr Matter, who is also a member of the University’s Southampton Marine and Maritime Institute and Adjunct Senior Scientist at Lamont-Doherty Earth Observatory Columbia University. “On the other hand, basalt is one of the most common rock type on Earth, potentially providing one of the largest CO2 storage capacity.”

Already, the project is storing 10,000 tonnes of CO2 a year and many other areas are highly rich in basaltic rocks, which means the same could be applied elsewhere.

“In the future, we could think of using this for power plants in places where there’s a lot of basalt and there are many such places,” said Martin Stute, at Columbia University in the US and part of the research team.

The big resource being used here is water – the process requires a lot of water, but thankfully, seawater can also be successfully used. Basalts are often found in proximity of oceans, so the problem could be solved with relative ease.

“The overall scale of our study was relatively small. So, the obvious next step for CarbFix is to upscale CO2 storage in basalt. This is currently happening at Reykjavik Energy’s Hellisheidi geothermal power plant, where up to 5,000 tonnes of CO2 per year are captured and stored in a basaltic reservoir.”

The project is part of research funded by the European Union. The investigation is part of the CarbFix project, a European Commission and U.S. Department of Energy funded programme to develop ways to store anthropogenic CO2 in basaltic rocks through field, laboratory and modelling studies.

 

The carbon nanofibers (seen above) were generated using a solar-powered electrochemical reactor that uses CO2 as its starting material. Image: George Washington University

Researchers turn CO2 seized from the air into valuable high-tech material

A team at George Washington University has found a way to hit two birds with one stone: mitigate climate change by pulling CO2 from the atmosphere and make a valuable material at the same time. The solar powered setup reacts a molten lithium carbonate in the presence of heat and an electrical current to produce carbon fibers, recently highly prized in engineering applications from cars and airplanes to wind turbines to tennis rackets.

The carbon nanofibers (seen above) were generated using a solar-powered electrochemical reactor that uses CO2 as its starting material. Image: George Washington University

The carbon nanofibers (seen above) were generated using a solar-powered electrochemical reactor that uses CO2 as its starting material. Image: George Washington University

The Solar Thermal Electrochemical Process or STEM first uses a concentrated solar power array to generate electricity and, secondly, heat the experimental device. Carbon dioxide from the air is pulled into the electrochemical reactor at one of two electrodes immersed in molten lithium carbonate. Running volts of electricity through the lithium carbonate at a specific temperature (750 degrees Celsius) kicks of a chemical reaction that dissolves the CO2 forming carbon nanofibres at the surface of one of the electrodes and lithium carbonate, which can be reused again in the next reaction.

Since it’s fully solar powered and uses CO2 directly fed from the atmosphere, the device basically makes carbon fibers out of thin air. This is definitely exciting considering a tonne of carbon nanofibers are valued on the market at $25,000. The researchers at George Washington claim, however, that they can scale their model to bring the cost down to $1,000 per tonne. Remember, all while pulling out CO2 from the atmosphere.

“One of the great threats facing our planet is climate change,” said Stuart Licht, of George Washington Univ.’s Dept. of Chemistry. “Rather than attempt to survive the climate change consequences of flooding, wild fires, starvation, economic disruption, human death and species extinction, we must mitigate the greenhouse gas carbon dioxide.”

To curb global warming you need to do two things: stop emitting (massive amounts) of CO2 and sequestrate the excess carbon that’s already in the atmosphere. Various carbon sequestrating techniques have been proposed, the most common being using pours rocks that absorb CO2 then burring them a mile or so underground. This is expensive and hardly makes a dint in global warming – you’d need to build thousands of carbon storage pits through the world.

How do we stop global warming while renewable technologies to meet our energy needs are still under development? Part of the answer may lie in an emerging transition technology called Carbon dioxide (CO2) Capture and Storage (CCS).

How do we stop global warming while renewable technologies to meet our energy needs are still under development? Part of the answer may lie in an emerging transition technology called Carbon dioxide (CO2) Capture and Storage (CCS).

What Licht and colleagues demonstrated is brilliant because the industry really needs these carbon fibers and the world needs to remove the excess carbon from the atmosphere. Of course, don’t imagine that carbon fiber plants will remove that much. For now, their prototype produces 10 grams of carbon nanofibres per hour, but it can be easily scaled. Licht says his team ran some numbers and found their setup could remove enough CO2 to decrease atmospheric levels down to those of the pre-industrial revolution within 10 years using a physical area less than 10% that of the Sahara desert. This sounds quite impractical at this point, but remember each solution and method that might help curb global warming helps. Just like renewable energy sources, there’s no one winning strategy. Decades from now, all sorts of carbon sequestrating and carbon removal methods will be employed. For instance, another interesting idea ZME Science reported earlier concerned reacting gaseous CO2 with low grade minerals such as magnesium and calcium silicate to produce limestone – a material used in constructions.

There are still a couple of things Licht and colleagues need to solve until their solution can compete with other carbon nanofibre producing methods. For one, their fibres are too short for any noteworthy practical use. They have to find a way to grow the fibres longer. “It’s like when you shear a sheep and you get wool,” James Tour, a nanoengineering and materials scientist at Rice University in Houston said for Science. “Those little wool fibres that first come off its back — you can’t make a blanket out of that. You have to somehow get it spun into long fibres that you can then put into a machine to get a wool sweater or blanket.”

Findings appeared in Nano Letters.

Worth more in the oceans: fish save billions of dollars each year by storing CO2 in the oceans

Whenever you’re eating a fish or some other marine creature, think just for a moment that it may actually be worth more as a CO2 storing machine than a food.

First of all, let’s just make this clear: we’re unsustainably eating fish. If we continue current trends, we’ll soon be facing a massive fish crisis, as depicted in the image above. As you can see for yourself, there are virtually no more unexploited fish stocks, by now over a third of all fish stocks have already collapsed, and the situation is getting worse and worse every year. To add insult to injury, a new study has concluded that fish are actually worth more for the CO2 storing services they offer than on your plate.

By assigning a dollar value to carbon stored in ocean ecosystems, two recent scientific reports are attempting to make nations reconsider the true worth of their fishing activities.

The first one, conducted by the Global Ocean Commission, roughly estimates that fish and other aquatic life in the high seas absorb carbon dioxide which would otherwise cause damage between $74 billion to $222 billion every year. A more localized research showed that in the UK waters alone, the figure is $20 million every year.

But here’s the really awesome thing – the world’s fishing industry is worth $16 billion – way less value than the services which fish provide! Strictly from an economic point of view, it would be better to ban fishing altogether!

“Fish are actually really important in the global carbon cycle, and they’ve been rather neglected,” said Clive Trueman of the University of Southampton, lead author of the deep-sea fish study.

This study highlights once again the value of animals, and the damage we are causing overexploiting the planet’s resources – if we don’t start changing things, it will almost certainly come back to haunt us.

“I really think to use our oceans sensibly, we need to look at all the services that they provide and then find those that contribute to human welfare and well-being the most, and try to encourage that,” added Rashid Sumaila, professor and director of the fisheries economics research unit at the University of British Columbia, who co-authored the Global Ocean Commission report.

So how exactly do fish store CO2 in the oceans?

Phytoplankton, the ocean’s basic life form, from the bottom of the food chain, absorbs billions of tons of carbon dioxide each year. But because phytoplankton swims close to the surface, if it reaches the surface, it reemits most of the CO2 back into the atmosphere – if it isn’t eaten by any other marine animals, that is. Fish come and eat the phytoplankton, but then again, they don’t really swim that deep either. That’s when the deep sea dwelling fish come into action – they come and eat the fish which ate the phytoplankton, taking the CO2 back to the depths of the oceans and storing it there.

“These big, bottom-feeding, predatory fish are basically capturing the moving animals and storing that carbon by killing them and keeping them at the bottom,” Trueman said. “It’s only once the carbon fixed by phytoplankton actually gets below about 100 to 200 meters that it’s not free to get back to the atmosphere.”

It’s amazing to think that recently, we had no idea this was happening. The services they are providing us are huge, and yet we knew nothing about them – and even now, we only understand the general mechanism.

“We really don’t know very much about them, and yet they’re doing something pretty useful for us,” Trueman said.

Hopefully, we’ll be able to understand more and act accordingly, protecting world fisheries – before it’s too late.

 

 

 

Sea urchin inspires carbon capture catalyst

British researchers from the University of Newcastle have discovered by mistake (how else?) that a species of sea urchin has the ability to use nickel and CO2 and turn it into shell.

sea urchin

The natural ability of the sea urchins to absorb CO2 could be a model for an effective carbon capture and storage system. Lately, taking inspiration from nature seems to be the best course of action – that’s what Gaurav Bhaduri and Lidija Šiller at the University of Newcastle, UK have discovered lately too.

Carbon capture and storage (CCS) is typically a slow and minutious process; basically what you want to do is separate the CO2 from flue gases and then store it somewhere where it would be modified, either in saline aquifers or converting it into mineral carbonates, including calcium carbonate – the main component of egg shell and other marine organism shells – including the sea urchin.

When the team at Newcastle looked at the larvae of sea urchins they found that there were high concentrations of nickel on their external skeletons. Working with these very small concentrations the researchers found that when they added them to a solution of carbon dioxide in water, the nickel completely removed the CO2 – a symple but extremely efficient system.

“It is a simple system,” Dr Lidija Siller from Newcastle University told explained. “You bubble CO2 through the water in which you have nickel nanoparticles and you are trapping much more carbon than you would normally – and then you can easily turn it into calcium carbonate. It seems too good to be true, but it works,” she added.

sea urchin 2

As well as being extremely cheap, nickel nanoparticles also work regardless of the pH – they work just as good in acidic and basic environments. But as promising as the results are, researchers still have to mineralise carbonic acid to environmentally friendly solid minerals including magnesium carbonate, calcium carbonate and dolomite, which could be used as a building material.

“The current challenge that we are addressing is to quantify the process. We would like to determine the reaction kinetics and exact yields. Once we have this information we plan to do a small continuous process in a lab-scale pilot plant.”

sea urchin 3

So if you get stung by a sea urchin, just remember – that little guy may actually hold the key to carbon storage, and as a result, fighting global warming.

Via BBC