GT/ New world record for CIGS solar cells
Energy & green technology biweekly vol.65, 29th February — 12th March
TL;DR
- CIGS solar cells achieve a new high, reaching 23.64% efficiency in electrical energy generation.
- Scientists create a microporous covalent organic framework for clean hydrogen peroxide production via photosynthesis.
- To achieve carbon neutrality by 2060, China needs 8–10 times more wind and solar power installations and increased transmission line construction.
- Nuclear power offers a solution, but handling nuclear waste remains a challenge; a new method aims to make nuclear waste more stable.
- Replacing 50% of animal products with alternatives by 2050 could free up land for renewable energy, reducing CO2 emissions.
- Warmer soils foster diverse active microbes, challenging previous assumptions about soil temperature’s impact on the carbon cycle.
- A novel method for measuring and removing sulfate from water could enhance nuclear waste treatments and improve water quality.
- Researchers discover pyrenoid-associated proteins in marine algae, suggesting independent evolution of pyrenoids in different algal groups.
- Black carbon poses a severe health risk, with a portable sensor proving as accurate as standard instruments in monitoring concentrations.
- Affordable sensors can expand air quality observation networks, aiding disease risk assessment and informing public health policies.
- And more!
Green Technology Market
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Latest Research
High-concentration silver alloying and steep back-contact gallium grading enabling copper indium gallium selenide solar cell with 23.6% efficiency
by Jan Keller, Klara Kiselman, Olivier Donzel-Gargand, Natalia M. Martin, Melike Babucci, Olle Lundberg, Erik Wallin, Lars Stolt, Marika Edoff in Nature Energy
Uppsala University is the new world record holder for electrical energy generation from CIGS solar cells. The new world record is 23.64 per cent efficiency. The measurement was made by an independent institute.The record results from a collaboration between the company First Solar European Technology Center (formerly known as Evolar) and solar cell researchers at Uppsala University.
“The measurements that we have made ourselves for this solar cell and other solar cells produced recently are within the margin of error for the independent measurement. That measurement will also be used for an internal calibration of our own measurement methods,” says Marika Edoff, Professor of Solar Cell Technology at Uppsala University, who is responsible for the study.
The previous world record was 23.35 per cent (Solar Frontier, Japan), preceded by 22.9 per cent (ZSW, Germany). Uppsala University has held the record before, the first time being in the 1990s in the research collaboration Euro-CIS.
“At one time we also held the record for a series-connected prototype. Even though it’s quite a long time since we held the cell record, we’ve often been just behind the best results and of course there are many relevant aspects to consider, such as the potential for scaling up to a large-scale process, where we have always been at the forefront,” Edoff says.
Solar cells are increasing rapidly worldwide and solar power accounted for just over 6 per cent of electricity around the globe in 2022 according to the International Energy Agency (IEA). The best solar modules of crystalline silicon, which is the most widely used material in solar cells, currently convert more than 22 per cent of sunlight to electric power and modern solar cells are both low cost and stable in the long term.
One target in solar cell research is to attain more than 30 per cent efficiency with reasonable production costs. The focus is very often on tandem solar cells, as being more efficient, but so far they have been too costly for large-scale use.
The world record of 23.64 per cent has been measured by the independent institute Fraunhofer ISE in Germany. The scholarly paper presents a thorough material and electrical analysis of the solar cell as well as a comparison with previous records for the same type of solar cell from other research institutions.
A solar cell’s most important properties are the ability to absorb light and the ability to transport energy to an electrical load. For this to succeed, the material must be able to absorb an optimal portion of sunlight while avoiding wasting this energy by converting it into heat within the solar cell.
CIGS solar cells consist of a glass sheet made of normal window glass that has been coated with several different layers, each of which has a specific task. The material that absorbs the sunlight consists of copper, indium, gallium and selenide (hence the acronym CIGS), with additions of silver and sodium. This layer is placed in the actual solar cell, between a back contact of metallic molybdenum and a transparent front contact. To make the solar cell as efficient as possible in separating out electrons, the CIGS layer is treated with rubidium fluoride. The balance between the two alkali metals, sodium and rubidium, and the composition of the CIGS layer are key to the conversion efficiency, i.e. the share of the complete solar spectrum that is converted to electric power in the solar cell.
When measurement institutes conduct their tests, they measure the solar cell efficiency using filtered light that mimics the sun in both intensity and spectrum. During measurement, the solar cell is kept at a controlled temperature and the independent institutes regularly send calibration solar cells to one another. To be registered as a world record, an independent measurement is required, which in this case was carried out by the measurement institute Fraunhofer ISE.
“Our study demonstrates that CIGS thin-film technology is a competitive alternative as a stand-alone solar cell. The technology also has properties that can function in other contexts, such as the bottom cell of a tandem solar cell,” Edoff says.
Several advanced measurement methods have been used to further understand the correlation between the efficiency and the solar cell structure: material from the solar cell has been characterised by nano-XRF (X-ray fluorescence spectroscopy) at the MAX IV facility in Lund, where a careful compositional analysis has been made. Transmission electron microscopy (TEM) at high resolution has been used to study cross sections of the solar cell, both composition as a function of depth and how the crystal grains are built up, as well as the interfaces between the layers. Using photoluminescence, the spectrum of the light emitted by the solar cell after excitation by a laser has been studied as a means to understanding how well the solar cell takes care of electrons internally. A solar cell that shines brightly has a lower share of internal heat losses than a solar cell that shines faintly. Finally, electrical measurement methods have been used to analyse the doping of the CIGS material.
“The fact that we now hold the world record means a lot for both Uppsala University and First Solar European Technology Center. For the CIGS technology, which is known for high reliability, a world record also means that it may offer a viable alternative for new applications in e.g. tandem solar cells. This is important for our research colleagues around the world. We hope that the analyses of the material and electric properties will provide a basis for further improvements in performance,” Edoff concludes.
Linkage-engineered donor–acceptor covalent organic frameworks for optimal photosynthesis of hydrogen peroxide from water and air
by Ruoyang Liu, Yongzhi Chen, Hongde Yu, Miroslav Položij, Yuanyuan Guo, Tze Chien Sum, Thomas Heine, Donglin Jiang in Nature Catalysis
Researchers at the National University of Singapore (NUS) have developed a microporous covalent organic framework with dense donor-acceptor lattices and engineered linkages for the efficient and clean production of hydrogen peroxide (H2O2) through the photosynthesis process with water and air.
Traditional industrial production of H2O2 via the anthraquinone process using hydrogen and oxygen, is highly energy-intensive. This approach employs toxic solvents and expensive noble-metal catalysts, and generates substantial waste from side reactions. In contrast, photocatalytic production of H2O2 from oxygen and water offers an energy-efficient, mild and clean route. Most importantly, it addresses the common drawbacks of existing photocatalytic systems, such as low activity, heavy use of additional alcohol sacrificial donors, and the necessity for pure oxygen gas input.
A research team led by Professor JIANG Donglin from the NUS Department of Chemistry has developed a new type of photocatalyst for the efficient artificial photosynthesis of H2O2 from water and air. The researchers constructed hexavalent covalent organic frameworks (COFs) in which the skeleton is designed to be donor-acceptor π columns for high-rate photo-induced charge generation and catalytic active sites. In parallel, the pore is engineered with hydraulically sensitivetrigonal microporous channels for immediate delivery of reactants water and oxygen. As a result, these hexavalent COFs produce H2O2 spontaneously and efficiently from water and atmospheric air when exposed to visible light in both batch and flow reactors. Under laboratory conditions, the COFs demonstrate a quantum efficiency of 17.5 per cent under visible light at 420 nm in batch reactors. This system can be developed to construct self-cleaning surfaces and for disinfection treatments.
Spatially resolved land and grid model of carbon neutrality in China
by Da Zhang, Ziheng Zhu, Shi Chen, Chongyu Zhang, Xi Lu, Xiliang Zhang, Xiaoye Zhang, Michael R. Davidson in Proceedings of the National Academy of Sciences
To become carbon neutral by 2060, as mandated by President Xi Jinping, China will have to build eight to 10 times more wind and solar power installations than existed in 2022. Reaching carbon neutrality will also require major construction of transmission lines.
China land use policies will also have to be more coordinated and focused on a nation-wide scale rather than be left to ad hoc decisions by local governments. That’s because 80% of solar power and 55% of wind power will have to be built within 100 miles of major population centers. These are the conclusions of a new study from researchers at Tsinghua University in Beijing and at the University of California San Diego.
“We know China has a very ambitious pathway to achieve carbon neutrality. We wanted to find out exactly what that entails,” said Michael Davidson, a senior author of that study and a professor at the School of Global Policy and Strategy and the Jacobs School of Engineering at UC San Diego.
One of the goals of the study is to inform renewable energy planning and policy in China. But the information is also crucial because China is currently the world’s biggest greenhouse gas emitter. So the country’s policies impact the global climate change picture and the planet’s future. Other countries can also learn from China’s successes and failures.
The study is based on an ambitious model that simulated China’s carbon neutral power grid in 2060 and what it would take to get there. The model looks at power generation resources and transmission line installations at an unprecedented resolution, considering parcels of land as small as 20 to 30 square kilometers. The model can also be applied to other countries.
As the researchers built and ran the model, the importance of land use became clearer. For example, China’s east, near the coast, will run out of land that can be used for renewable energy plants. As a result, any solar installations in that area need to be built on a smaller scale, on residential and commercial buildings, for example.
The model shows that China will need to build two to four terawatts each of solar and wind capacity. Construction of terawatt-level energy storage will also be required. Ultra-high voltage transmission between the country’s provinces should double or triple to ensure power supplies are delivered where they are needed.
Next steps include building in flexible demand in the model, considering a larger range of land use factors such as conservation priorities, and examining the implication of large changes in the mix of power resources and emissions reduction activities in sectors other than electricity.
Neutron capture reaction cross-section of 79Se through the 79Se(d,p) reaction in inverse kinematics
by N. Imai, M. Dozono, S. Michimasa, T. Sumikama, S. Ota, S. Hayakawa, et al in Physics Letters B
Nuclear power is considered one of the ways to reduce dependence on fossil fuels, but how to deal with nuclear waste products is a concern. Radioactive waste products can be turned into more stable elements, but this process is not yet viable at scale. New research led by physicists from the University of Tokyo reveals a method to more accurately measure, predict and model a key part of the process to make nuclear waste more stable. This could lead to improved nuclear waste treatment facilities and also to new theories about how some heavier elements in the universe came to be.
The very word “nuclear” can be a bit of a trigger for some people, understandably so in Japan, where the atomic bomb and Fukushima disaster are some of the pivotal moments in its modern history. Yet, given the relative scarcity of suitable space in Japan for renewable forms of energy like solar or wind, nuclear power is considered to be a critical part of the effort to decarbonize the energy sector. Because of this, researchers are hard at work trying to improve safety, efficiency and other matters relating to nuclear power. Associate Professor Nobuaki Imai from the Center for Nuclear Study at the University of Tokyo and his colleagues think they can contribute to improving a key aspect of nuclear power, the processing of waste.
“Broadly speaking, nuclear power works by boiling water using self-sustaining nuclear decay reactions. Unstable elements break apart and decay, releasing heat, which boils water, driving turbines. But this process eventually leaves behind unusable waste that is still radioactive,” said Imai. “This waste can remain radioactive for hundreds of thousands of years, so it is usually buried deep underground. But there is a growing desire to explore another way, a way in which unstable radioactive waste can be made more stable, avoiding its radioactive decay and rendering it far safer to deal with. It’s called transmutation.”
Transmutation is like the opposite of nuclear decay; instead of an element breaking apart and releasing radiation, a neutron can be added to an unstable element changing it into a slightly heavier version of itself. Depending on the initial substance, this new form can be stable enough to be considered safe. The problem is, though this process has been generally known for some time, it has been impossible to quantify sufficiently accurately to carry the idea on to the next stage and ideally produce prototype new-generation waste management facilities.
“The idea actually came from a surprising source: colliding stars, specifically neutron stars,” said Imai. “Following recent observations of gravitational waves emanating from neutron star mergers, researchers have been able to better understand the ways neutrons interact and their ability to modify other elements. Based on this, we used a range of instruments to narrow our focus on how the element selenium, a common nuclear waste product, behaves when bombarded by neutrons. Our technique allows us to predict how materials absorb neutrons and undergo transmutation. This knowledge can contribute to designs for nuclear waste transmutation facilities.”
It’s difficult for researchers to make these kinds of observations; in fact, they are not able to directly observe acts of transmutation. Rather, the team can observe how much of a sample does not transmute, and by taking readings to know that transmutation did in fact take place, they can estimate, albeit very accurately, how much of the sample did transmute.
“We are confident that our measurements accurately reflect the real rate of transmutation of unstable selenium into a more stable form,” said Imai. “We are now planning to measure this for other nuclear waste products. Hopefully, this knowledge will combine with other areas required to realize nuclear waste treatment facilities, and we might see these in the coming decades. Though our aims are to improve nuclear safety, I find it interesting that there is a bidirectional relationship between this research and astrophysics. We were inspired by colliding neutron stars, and our research can impact how astrophysicists look for signs of nuclear synthesis, the creation of elements in stars, to better understand how elements heavier than iron were made, including those essential for life.”
A protein transition can free up land to tap vast energy and negative emission potentials
by Oscar Rueda, José M. Mogollón, Fabian Stenzel, Arnold Tukker, Laura Scherer in One Earth
Researchers report that replacing 50% of animal products with alternative proteins by 2050 could free up enough agricultural land to generate renewable energy equivalent in volume to today’s coal-generated power while simultaneously removing substantial CO2 from the atmosphere.
The study is based on a CO2-removal method known as “bioenergy with carbon capture and storage” (BECCS), which involves cultivating quickly growing crops whose biomass can then be stored permanently in geological formations or used as a feedstock to produce renewable energy. Most studies of BECCS assume that the land required to grow this biomass would threaten food security or be attained via agricultural expansion into regions of natural vegetation, which has negative implications for biodiversity, but the researchers of the new study had another idea: to combine BECCS with a dietary shift.
“Animal-source foods use resources inefficiently because animals consume more food than they provide, and feeding the animals requires considerable land and water,” write the researchers, led by environmental scientist Oscar Rueda of Leiden University. “We show that a protein transition could free up extensive resources for BECCS to achieve substantial energy and carbon-removal potentials.”
“Our results show that replacing animal products can help unlock vast energy and negative emission potentials via BECCS while avoiding agricultural expansion and securing water supply for people and ecosystems,” the researchers write. “Even modest adoption levels of alternative proteins could free up large agricultural areas.”
Their model suggested that even a 30% reduction in animal-product consumption would enable significant carbon removal and renewable-energy production. If 30% of animal products were replaced by alternative proteins, it would free up enough area to generate between 15.8 and 29.1 EJelec per year and remove 3.5–7.2 Gt of CO2 per year. (Currently, coal power generates 35 EJelec per year and results in 10 Gt of CO2 emissions.)
The team also analyzed global geographical locations for their potential for biomass production and CO2 storage. They found that most countries have the geological potential to sequester CO2 from BECCS within their borders. In particular, the researchers note that “the US, Europe, and China stand out for their considerable sequestration potential.”
They also demonstrated that planting biomass crops for BECCS on freed-up agricultural land would be more effective at carbon removal than natural revegetation. If 100% of animal products were replaced by alternatives, using those areas for BECCS for around 60 years could remove 700 Gt more CO2 than natural revegetation of those same areas. After that period, the researchers say, the areas could revert to natural vegetation, and the researchers note that BECCS is no replacement for nature.
“On the one hand, BECCS could use a fraction of the freed-up land to boost climate mitigation while producing renewable energy,” says Rueda. “On the other hand, natural revegetation could be preferable in many areas, especially those that may be close to their natural state.”
The researchers say that a protein transition is feasible, but it’s uncertain what this transition would look like and whether it would be dominated by traditional plant-based proteins or lab-based alternatives.
“Market research shows that alternative proteins, from sources such as plants, microorganisms, and tissue culture, could replace 10%-30% of animal products in 2030 and 30%-70% in 2050,” the researchers write. “Emerging research on novel alternative proteins can further clarify uncertainties of adoption and impacts.”
Soil warming increases the number of growing bacterial taxa but not their growth rates
by Dennis Metze, Jörg Schnecker, Coline Le Noir de Carlan, Biplabi Bhattarai, Erik Verbruggen, Ivika Ostonen, Ivan A. Janssens, Bjarni D. Sigurdsson, Bela Hausmann, Christina Kaiser, Andreas Richter in Science Advances
Warmer soils harbour a greater diversity of active microbes, according to a new study from researchers at the Centre for Microbiology and Environmental Systems Science (CeMESS) at the University of Vienna. The study represents a significant shift in our understanding of how microbial activity in the soil influences the global carbon cycle and possible feedback mechanisms on the climate. Until now, scientists have assumed that higher soil temperatures accelerate the growth of microbes, thus increasing the release of carbon into the atmosphere. However, this increased release of carbon is actually caused by the activation of previously dormant bacteria.
“Soils are Earth’s largest reservoir of organic carbon,” states Andreas Richter, lead author of the study and professor at the Centre for Microbiology and Environmental Systems Science. Microorganisms silently dictate the global carbon cycle, breaking down this organic matter thereby releasing carbon dioxide. As temperatures rise — a guaranteed scenario under climate change-microbial communities are thought to emit more carbon dioxide, further accelerating climate change in a process known as soil carbon-climate feedback.
“For decades, scientists have assumed that this response is driven by increased growth rates of individual microbial taxa in a warmer climate,” explains Richter. In this study, the researchers visited a subarctic grassland in Iceland that has undergone over half a century of geothermal warming, resulting in elevated soil temperatures compared to surrounding areas. By collecting soil cores and using cutting-edge isotope probing techniques, the team identified active bacterial taxa, comparing their growth rates at both ambient and elevated temperatures, the latter being 6 °C higher.
“We saw that more than 50 years of consistent soil warming increased microbial growth at the community level,” says Dennis Metze, PhD student and primary author of the study. “But remarkably, the growth rates of microbes in warmer soils were indistinguishable to those at normal temperatures.” The pivotal difference lay in the bacterial diversity: Warmer soils harboured a more varied array of active microbial taxa.
“Understanding the complexities of the soil microbiome’s reaction to climate change has been a considerable challenge, often rendering it a ‘black box’ in climate modeling,” adds Christina Kaiser, associate professor at the Centre.
This new finding transcends the traditional focus on community-aggregated growth, setting the stage for more accurate predictions of microbial behavior and its consequent effects on carbon cycling in the evolving climate scenario. The insights gained from this study illuminate the diverse microbial responses to warming and are vital for forecasting the soil microbiome’s impact on future carbon dynamics.
Distinct roles of direct and indirect electrification in pathways to a renewables-dominated European energy system
by Felix Schreyer, Falko Ueckerdt, Robert Pietzcker, Renato Rodrigues, Marianna Rottoli, Silvia Madeddu, Michaja Pehl, Robin Hasse, Gunnar Luderer in One Earth
A key step to achieving climate neutrality in the European Union is to rapidly shift from fossil fuels to electric technologies powered by renewable energies, a new study shows. At the same time, hydrogen produced from electricity will also be indispensable in hard-to-electrify sectors such as aviation, shipping and chemicals. By 2050, electrification and hydrogen are the key strategies to reach climate neutrality based on renewable power. Future EU transformation scenarios modeled by scientists from the Potsdam Institute for Climate Impact Research PIK investigate the roles of electrification and hydrogen and find that shares of 42–60% for electricity and 9–26% for hydrogen-based energy are required in total energy consumption by 2050.
“Previous research has shown that our power system can be transformed to renewable sources like wind and solar at low cost and low environmental impact. However, the next question is how this renewable electricity can be used to substitute fossil fuel use in the buildings, industry and transport sectors. Our analysis shows that the direct use of electricity, for example, via electric cars and heat pumps, is critical for a broad range of sectors, while the conversion of electricity to hydrogen is important only for few applications,” says Felix Schreyer, PIK scientist and lead author of the study.
The study is the first to analyse the interplay of electrification and hydrogen in EU climate neutrality scenarios at greater sectoral detail. The analysis shows higher potentials for electrification and identifies a more confined deployment range for hydrogen-based energy than earlier studies. Using the energy-economy model REMIND, PIK-scientists investigated plausible combinations of both strategies in EU energy system transformation pathways under different scenario assumptions. They found that, across scenarios, direct electrification is the dominant strategy for passenger cars and low-temperature heating in buildings and industry, while hydrogen and synthetic fuels produced from electricity are needed primarily for aviation, shipping, the chemical industry and as electricity storage. Hence, electrification and hydrogen are largely complementary, while they compete for a small share of only about 15% of final energy. These uncertain segments include sectors like truck transport and high-temperature industrial process heat.
“Ramping up renewable electricity supply and switching to electric technologies wherever possible is by far the fastest and cheapest way of eliminating carbon emissions in most sectors. We therefore expect the share of electricity in final energy to increase from 20% to 42–60%,” says co-author Gunnar Luderer, leader of the Energy Systems Group at PIK.
This is because electric technologies are increasingly available and use electricity very efficiently, while the conversion to hydrogen and synthetic fuels and their combustion come with significant energy losses. Overall, EU electricity demand increases across their scenarios by 80–160% in 2050 depending on the amount of hydrogen imports and the role of electrification and hydrogen in uncertain sectors. This means that around twice as much power as today will have to be produced by then.
The authors also discuss the current state of EU policy with regards to electrification and hydrogen and outline three critical cornerstones for a successful transformation: Policy-making should 1) prioritise electrification and hydrogen respectively in sectors where they are preferred across all scenarios, 2) remove barriers to renewable power expansion and 3) incentivize the scale-up of hydrogen supply chains.
“Our study highlights that policymakers should respect the different sectoral roles of both strategies: By promoting electrification via electric applications for road transport and heating while prioritising hydrogen and synthetic fuels for applications where they are indispensable,” says PIK scientist and co-author Falko Ueckerdt.
A charge-neutral organic cage selectively binds strongly hydrated sulfate anions in water.
by Liuyang Jing, Evelyne Deplazes, Jack K. Clegg, Xin Wu in Nature Chemistry
Scientists have developed a new method to measure and remove sulfate from water, potentially leading to cleaner waterways and more effective nuclear waste treatments.
A collaborative team from The University of Queensland and Xiamen University in China has designed a cage-like molecule to trap sulfate, a naturally occurring ion, in water. Professor Jack Clegg from UQ’s School of Chemistry and Molecular Biosciences said controlling the sulfate concentration in water is a significant challenge in health, industry and environmental management.
“Sulfate is a very common and important ion,” Professor Clegg said. “In low quantities in the human body, sulfate has diverse metabolic roles such as eliminating toxins and helping drugs work effectively. “But in the environment, too much sulfate can pollute drinking water and accelerate the corrosion of pipes.
“The presence of sulfate also causes problems when immobilising radioactive wastes. “Being able to monitor and completely remove sulfate in water has great potential across many areas.”
The researchers developed a molecule that measures and traps sulfate in water with a high degree of selectivity. This ‘molecular trap’ can be prepared inexpensively from off-the-shelf chemicals. Dr Xin Wu, a former DECRA fellow at UQ now based at Xiamen University, said while there are enormous benefits from cheaply and easily measuring sulfate levels, the molecular trap’s ability to capture negatively charged chemicals from water is also valuable.
“Being able to stabilise a highly negatively charged chemical such as sulfate inside a charge-neutral cavity is a remarkable feature of our molecule,” Dr Wu said. “This mimics the function of naturally occurring sulfate-binding proteins.
“The technology could also have applications in medicine, such as helping to funnel chloride and bicarbonate ions through cell membranes to treat diseases that involve defective ion transport such as cystic fibrosis. “This is just the beginning — we’re excited to see how this fundamental science can be applied in all sorts of fields.”
Pyrenoid proteomics reveals independent evolution of the CO 2 -concentrating organelle in chlorarachniophytes
by Rena Moromizato, Kodai Fukuda, Shigekatsu Suzuki, Taizo Motomura, Chikako Nagasato, Yoshihisa Hirakawa in Proceedings of the National Academy of Sciences
Plants and algae fix carbon through photosynthesis, which converts CO2 to organic carbon. This biological process is catalyzed by the Rubisco enzyme, the most abundant protein on Earth. In many algae, Rubisco is densely packed into a microcompartment called the pyrenoid, which plays an important role in the CO2 accumulation in aquatic environments. Notably, approximately one-third of global carbon fixation is estimated to occur within algal pyrenoids. Apart from Rubisco, the primary component of pyrenoids, the pyrenoid-associated proteins in most algae remain unclarified.
In this study, pyrenoid-associated proteins in a marine chlorarachniophyte alga were identified through a proteomic approach. Some of these proteins are apparently involved in pyrenoid construction and CO2 concentration. Interestingly, various pyrenoid-associated proteins have been reported among the algae studied to date, suggesting that CO2-fixing organelles evolved independently in each algal group. This is an example of convergent evolution at the molecular level.
Genetic engineering of plants using algal genes is underway to increase the photosynthetic performance. The pyrenoid-associated proteins reported herein are a potential basis for improving crop productivity in the future.
A Long-Term Comparison between the AethLabs MA350 and Aerosol Magee Scientific AE33 Black Carbon Monitors in the Greater Salt Lake City Metropolitan Area
by Daniel L. Mendoza, L. Drew Hill, Jeffrey Blair, Erik T. Crosman in Sensors
Black carbon is the most dangerous air pollutant you’ve never heard of. Its two main sources, diesel exhaust and wood smoke from wildfires and household heating, produce ultrafine air particles that are up to 25 times more of a health hazard per unit compared to other types of particulate matter. Despite its danger, black carbon is understudied due to a lack of monitoring equipment. Regulatory-standard sensors are wildly expensive to deploy and maintain, resulting in sparse coverage in regions infamous for poor air quality, such as the greater Salt Lake City metropolitan area in Utah.
A University of Utah-led study found that the AethLabs microAeth MA350, a portable, more affordable sensor, recorded black carbon concentrations as accurately as the Aerosol Magee Scientific AE33, the most widely used instrument for monitoring black carbon in real time. Researchers placed the portable technology next to an existing regulatory sensor at the Bountiful Utah Division of Air Quality site from Aug. 30, 2021-Aug. 8, 2022. The AethLabs technology recorded nearly identical quantities of black carbon at the daily, monthly and seasonal timescales. The authors also showed that the microAeth could distinguish between wildfire and traffic sources as well as the AE33 at longer timescales.
Because black carbon stays close to the source, equipment must be localized to yield accurate readings. The microAethsensor’s portability would allow monitoring at remote or inaccessible stationary sites, as well as for mobile use.
“Having a better idea of black carbon exposure across different areas is an environmental justice issue,” said Daniel Mendoza, research assistant professor of atmospheric sciences at the University of Utah and lead author of the study. “The Salt Lake Valley’s westside has some of the region’s worst air quality partly because it’s closest to pollution sources, but we lack the ability to measure black carbon concentrations accurately. Democratizing data with reliable and robust sensors is an important first step to safeguarding all communities from hazardous air pollution.”
Black carbon pollutants are a type of fine particulate matter (PM2.5), a class of air particles small enough to be inhaled into the lungs and absorbed into the bloodstream. Black carbon is true soot, produced when hydrocarbons do not fully burn, and has been shown to migrate into the heart, brain, fetal tissue, and other biological systems.
“The combination of increasing wildfires driven by anthropogenic climate change and steady population growth along the Wasatch Front in coming decades will result in new pollution challenges that Utah will have to face,” said Erik Crosman, assistant professor of environmental sciences at West Texas A&M University and a co-author of the study.”The portable MA350 ‘micro’ aethalometer could be utilized in building a better spatial observational network of accurate but lower cost black carbon sensors across the region.”
Though research suggests exposure to black carbon is 10 to 25 times more hazardous to respiratory and cardiovascular health than other PM2.5, long-term health outcomes are largely unknown. An accurate observation network is the first step to establishing disease risk and creating effective public health policies. This study, funded by the Salt Lake City Corporation, aims to help regions with poor air quality establish a baseline of black carbon distribution.
“It’s crucial that we target our measurements to identify the largest and most relevant black carbon sources,” said Drew Hill, a study coauthor who leads data science and applied research work at AethLabs. “We’ve added a feature rooted in physical principles to provide real-time estimates of the amount of measured black carbon produced by fossil fuel burning versus wood burning to allow researchers and policy makers to triangulate such sources.”
Having established the portable sensor’s accuracy and regional relevance, the researchers are measuring black carbon levels around the Salt Lake Valley, including testing concentrations present inside school buildings.
“First, you need to get readings. In some neighborhoods you could look at air quality concentrations, then look at the cancer or other disease rate in that neighborhood,” said Mendoza, who is also an adjunct assistant professor in the Division of Pulmonary Medicine at University of Utah Health. “Getting measurements with a high degree of accuracy, now we can really think about health and policy avenues to really protect everyone’s lung health.”
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