Researchers analyze global potential for ‘negative emissions energy’ using electricity from renewable sources to generate hydrogen fuel and capture carbon dioxide
Limiting global warming to 2 degrees Celsius will require not only reducing emissions of carbon dioxide, but also active removal of carbon dioxide from the atmosphere. This conclusion from the Intergovernmental Panel on Climate Change has prompted heightened interest in “negative emissions technologies.”
A new study published June 25 in Nature Climate Change evaluates the potential for recently described methods that capture carbon dioxide from the atmosphere through an “electrogeochemical” process that also generates hydrogen gas for use as fuel and creates by-products that can help counteract ocean acidification.
First author Greg Rau, a researcher in the Institute of Marine Sciences at UC Santa Cruz and visiting scientist at Lawrence Livermore National Laboratory, said this technology significantly expands the options for negative emissions energy production.
The process uses electricity from a renewable energy source for electrolysis of saline water to generate hydrogen and oxygen, coupled with reactions involving globally abundant minerals to produce a solution that strongly absorbs and retains carbon dioxide from the atmosphere. Rau and other researchers have developed several related methods, all of which involve electrochemistry, saline water, and carbonate or silicate minerals.
“It not only reduces atmospheric carbon dioxide, it also adds alkalinity to the ocean, so it’s a two-pronged benefit,” Rau said. “The process simply converts carbon dioxide into a dissolved mineral bicarbonate, which is already abundant in the ocean and helps counter acidification.”
The negative-emissions energy approach that has received the most attention so far is known as “biomass energy plus carbon capture and storage” (BECCS). This involves growing trees or other bioenergy crops (which absorb carbon dioxide as they grow), burning the biomass as fuel for power plants, capturing the emissions, and burying the concentrated carbon dioxide underground.
“BECCS is expensive and energetically costly. We think this electrochemical process of hydrogen generation provides a more efficient and higher capacity way of generating energy with negative emissions,” Rau said.
He and his coauthors estimated that electrogeochemical methods could, on average, increase energy generation and carbon removal by more than 50 times relative to BECCS, at equivalent or lower cost. He acknowledged that BECCS is farther along in terms of implementation, with some biomass energy plants already in operation. Also, BECCS produces electricity rather than less widely used hydrogen.
“The issues are how to supply enough biomass and the cost and risk associated with putting concentrated carbon dioxide in the ground and hoping it stays there,” Rau said.
The electrogeochemical methods have been demonstrated in the laboratory, but more research is needed to scale them up. The technology would probably be limited to sites on the coast or offshore with access to saltwater, abundant renewable energy, and minerals. Coauthor Heather Willauer at the U.S. Naval Research Laboratory leads the most advanced project of this type, an electrolytic-cation exchange module designed to produce hydrogen and remove carbon dioxide through electrolysis of seawater. Instead of then combining the carbon dioxide and hydrogen to make hydrocarbon fuels (the Navy’s primary interest), the process could be modified to transform and store the carbon dioxide as ocean bicarbonate, thus achieving negative emissions.
“It’s early days in negative emissions technology, and we need to keep an open mind about what options might emerge,” Rau said. “We also need policies that will foster the emergence of these technologies.”
The Latest on: Negative emissions technology
via Google News
The Latest on: Negative emissions technology
Trump closes in on proposal to undo Obama’s climate rule
on August 17, 2018 at 9:02 am
The Trump administration will shortly release its plan to replace Barack Obama’s ambitious attempts to curb greenhouse gas emissions. Former US President ... something which could see a revival of the ... […]
3D-Printed Concrete 'Lotus House' Explores Sustainable Methods of Construction
on August 17, 2018 at 8:04 am
Now, students at Washington University in St. Louis (WashU) are investigating how 3D printing technology can be ... construction that typically has a negative effect on the environment, generating hig... […]
‘Carbon negative, dollar positive’: Initiative aspires to turn greenhouse gas into profitable products
on August 17, 2018 at 6:54 am
“We believe innovations in carbon dioxide removal and utilization technologies can generate a carbon-negative, dollar-positive effect that will reduce emission footprints ... to support researchers th... […]
Midwest Energy Emissions' (MEEC) CEO Richard MacPherson on Q2 2018 Results - Earnings Call Transcript
on August 14, 2018 at 8:38 pm
We help capture mercury emissions using our patented SEA technology, which is short for Sorbent Enhancement ... Adjusted EBITDA in the second quarter of 2018 was negative $0.9 million compared to $1.2 ... […]
Guest post: Why BECCS might not produce ‘negative’ emissions after all
on August 14, 2018 at 4:16 am
Bioenergy crops with carbon capture and storage (BECCS) is, perhaps, the most prominent of the various negative emissions techniques. There are many attractive features, since this technology would pr... […]
Advanced Catalysis Technology
on August 8, 2018 at 2:19 pm
Around the world, legislation on vehicle emissions has developed over the years to meet a range of policy objectives, with the main driver for regulation being the reduction of negative impacts to cli... […]
How UNDP is promoting climate friendly and energy efficient technology to save the ozone layer
on August 5, 2018 at 11:09 pm
Depletion of the ozone layer would allow increased ultraviolet radiation to reach the earth, resulting in global warming, higher incidence of skin cancers and eye cataracts, more-compromised immune sy... […]
Negative emissions technology and global warming
on August 4, 2018 at 10:07 pm
We are warned that Melbourne and Sydney should prepare for 50-degree Celsius days under the Paris Agreement global warming limit of 2 degrees. To avoid 2 degrees average global warming before 2100, wi... […]
'Electrogeochemistry' captures carbon, produces fuel, offsets ocean acidification
on June 25, 2018 at 8:03 am
First author Greg Rau, a researcher in the Institute of Marine Sciences at UC Santa Cruz and visiting scientist at Lawrence Livermore National Laboratory, said this technology significantly expands th... […]
via Bing News