Solar Energy

Nations rally behind renewables at COP28 climate talks

Published

11 months ago

December 3, 2023

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Nations rally behind renewables at COP28 climate talks

By Talek Harris, Nick Perry and Laurent Thomet

Dubai (AFP) Dec 2, 2023

Nearly 120 nations pledged to triple the world’s renewable energy within seven years at UN climate talks Saturday as the United States pushed to crank up nuclear capacity and slash methane emissions.

With smoggy skies in Dubai highlighting the challenges facing the world, leaders at the COP28 conference threw their support behind voluntary pledges aimed at ramping up alternatives to fossil fuels.

A massive deployment of solar, wind, hydroelectric and other renewables is crucial to efforts to replace planet-heating coal, oil and gas and achieve net-zero carbon emissions by 2050.

– Fossil fuel fight –

But COP28 negotiators face far tougher talks on the fate of fossil fuels over the next two weeks.

“Everyone stuck to their traditional positions,” said one who spoke on condition of anonymity.

But on clean energy, more than half of all nations signed up to a commitment to triple global renewable capacity and double energy efficiency by 2030, the COP28’s Emirati president said.

However, major oil producers including Saudi Arabia, Russia and Iran did not join, nor is top consumer China on the list.

“I do need more, and I’m kindly requesting all parties to come on board as soon as possible please,” COP28 president Sultan Al Jaber told delegates.

Clean power advocates welcomed the commitment but said it must be accompanied by the phaseout of dirtier forms of energy.

“The future will be powered by solar and wind, but it won’t happen fast enough unless governments regulate fossil fuels out of the way,” said Kaisa Kosonen, the head of Greenpeace’s COP28 delegation.

Jaber also announced a pledge by oil and gas companies responsible for 40 percent of global production — including Saudi giant Aramco and the UAE firm ADNOC he heads — to decarbonise their operations by 2050 and curb methane emissions.

But the pledges do not include the pollution when the fuels are burned by their customers, and were criticised for repackaging previous, non-binding commitments.

“This charter is proof that voluntary commitments from the oil and gas industry will never foster the level of ambition necessary to tackle the climate crisis,” said Melanie Robinson of the World Resources Institute, a nonprofit research body.

– ‘Destructive’ methane –

It comes after the US Environmental Protection Agency said it would tighten curbs on methane emissions from its oil and gas industry.

The new standards will phase in the elimination of routine flaring of natural gas produced by oil wells, and require comprehensive monitoring of methane leaks from wells and compression stations.

Methane is responsible for about one-third of the warming from greenhouse gases, second only to CO2.

“It is fugitive gas, and it just is out there doing damage,” said US climate envoy John Kerry, who met his Chinese counterpart Xie Zhenhua in Dubai Saturday to discuss how to curb the gas.

Their meeting followed an agreement with the US earlier this month where China for the first time agreed to include all greenhouse gases in its next national climate pledge for 2035.

Kerry also announced that Turkmenistan — which leaks more methane per unit of oil and gas than any other country — had signed up to an existing pledge to curb these harmful emissions.

The energy sector is the second-largest source of human-caused methane emissions.

Agriculture is the first, accounting for a quarter of methane emissions, mostly from livestock.

The US also joined a coalition of dozens of nations committed to phasing out coal power plants whose emissions cannot be captured.

– Nuclear option –

While COP28 rallied behind renewables, Washington led a call by more than 20 nations to triple nuclear energy capacity by 2050.

In a declaration, countries ranging from Britain to Ghana, Japan and several European nations said nuclear power had a “key role” in achieving carbon neutrality by mid-century.

But its use as a cleaner alternative to fossil fuels is highly controversial, with many environmental groups warning about safety risks and the disposal of nuclear waste.

Yet Kerry insisted “you can’t get to net zero 2050 without some nuclear”.

Environmental group 350.org said the 2011 Fukushima nuclear disaster in Japan highlighted the dangers.

“We don’t have time to waste on dangerous distractions like nuclear energy,” said its North America director Jeff Ordower.

More than 50 world leaders took the stage at COP28 for the second day in a row, with US Vice President Kamala Harris announcing a $3 billion contribution to a fund to help developing countries with energy transition and the effects of climate change — Washington’s first pledge to it since 2014.

Pledges made so far at the COP28 climate talks
Paris (AFP) Dec 2, 2023 -
The COP28 climate talks in Dubai have begun with a flurry of announcements promising action on global warming, led by its big-spending, oil-rich host the United Arab Emirates.

But observers have warned that the headline-grabbing pledges could distract from the real battles on fossil fuels and negotiating a formal COP28 text at the end of the two-week talks.

As pressure builds during what is expected to be the hottest year on record, here are some major funding pledges and declarations announced so far at COP28.

– Loss and damage –

The first day of the talks Thursday saw the launch of a landmark “loss and damage” fund to help vulnerable countries cope with the increasingly costly and damaging impacts of climate disasters.

The UAE and Germany pledged $100 million each, France $109 million, $50 million from Britain, $25 million from Denmark and $17.5 million from the United States, the world’s biggest historical polluter.

Campaigners said the US offering was woefully inadequate.

The total committed as of Saturday was some $656 million, according to a tally by the Natural Resources Defense Council, an environmental advocacy group.

That falls vastly short of the $100 billion a year that developing nations — which have historically been least responsible for greenhouse gas emissions — have said are needed to cover losses from natural disasters.

– Tripling renewables –

At least 116 countries committed Saturday to triple renewable energy capacity worldwide by 2030 and double the annual rate of energy efficiency improvements.

G20 nations, which account for nearly 80 percent of global greenhouse gas emissions, paved the way for a deal when they endorsed the renewable energy goal in September.

While supporters are expected to push for the pledge to be included in the final outcome of the talks, there are fears that the COP28 hosts were willing to shunt the more ambitious targets into voluntary deals.

– Fossil fuels –

The US committed to phasing out its existing unabated coal plants as it joined the Powering Past Coal Alliance (PPCA) Saturday.

Abatement generally means when the emissions from a power plant are captured before going into the atmosphere.

Global CO2 emissions from coal-fired power plants reached a new high in 2022 and the US has the world’s third-biggest capacity behind China and India.

Colombia became one of the largest fossil fuel producers to join the Fossil Fuel Non-Proliferation Treaty Initiative, a movement led by climate vulnerable island nations to end new development of coal, oil and gas.

Meanwhile, 50 oil and gas companies representing 40 percent of global production also pledged to decarbonise their operations by 2050. But the non-binding agreement does not include emissions when their fuels are burned by customers.

– Tripling nuclear –

More than 20 countries led by the US called Saturday for the tripling of world nuclear energy capacity by 2050. While nuclear generates almost no greenhouse gases, the Fukushima nuclear disaster in Japan in 2011 dealt it a severe blow.

But experts and activists point to the fact that new nuclear plants can take decades, while renewable energy is rising fast.

– Food and farming –

More than 130 countries have agreed to prioritise food and agriculture systems in their national climate plans.

The non-binding declaration was welcomed by observers, with food systems estimated to be responsible for roughly a third of human-made greenhouse gases.

But some criticised it for lacking concrete goals — and not mentioning fossil fuels or signalling any change to more sustainable diets.

– Healthy future? –

Over 120 countries signed up to a declaration to “place health at the heart of climate action”. It called for governments to step up action on climate-related health impacts like extreme heat, air pollution and infectious diseases.

Almost nine million people a year die from polluted air, while 189 million are exposed to extreme weather-related events.

The declaration notes “the benefits for health from deep, rapid, and sustained reductions in greenhouse gas emissions”, but makes no direct reference to the fossil fuels responsible for most human-caused pollution. COP28’s themed day on health is Sunday.

– UAE climate investment fund –

The UAE said it is putting $30 billion into a new private climate investment fund.

The oil-rich COP28 host said that the fund, called Alterra, would partly try to focus on climate projects in the developing world, and hoped to stimulate investments totalling $250 billion by 2030.

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Solar Energy

Sandia evaluates heat shields for Mars Sample Return and Titan missions

Published

2 days ago

October 16, 2024

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Sandia evaluates heat shields for Mars Sample Return and Titan missions

by Clarence Oxford

Los Angeles CA (SPX) Oct 16, 2024

Sandia National Laboratories’ National Solar Thermal Test Facility is utilizing solar energy to simulate the intense heat experienced during atmospheric reentry and hypersonic flight. The latest tests aim to support NASA missions, including the Mars Sample Return campaign, a joint effort with the European Space Agency to bring Martian rock samples to Earth for analysis. These samples could reveal evidence of ancient life and aid preparations for future human missions to Mars.

As part of the Mars Sample Return mission, a Sample Retrieval Lander would carry the heaviest payload ever sent to Mars, along with a rocket for launching the collected samples into Martian orbit. Heat shield materials for the lander recently underwent testing at Sandia, said Sandia engineer and test director Ken Armijo. “This would be the first mission to return rocks from Mars to Earth; it’s got a bigger payload,” Armijo explained. “The heavier the payload and the bigger the entry vehicle, the hotter the vehicle gets during atmospheric entry, and the better the heat shield needs to be.”

Sandia’s solar testing facility uses hundreds of heliostat mirrors to focus sunlight on samples up to three feet wide, simulating atmospheric conditions on different planets. Unlike arc jets and lasers, which consume significant power, this approach saves between 15,000 to 60,000 kilowatts per test, equivalent to running 5,000 to 20,000 clothes dryers simultaneously.

The facility’s solar power tower, 200 feet tall and equipped with 212 heliostats, provides a unique environment for testing materials under high solar flux and heat. “We have high flux and high flux distribution on the Solar Tower,” said Armijo. The facility can simulate hypersonic flight conditions and accommodate large test samples, including full aircraft sections. Sunlight is concentrated up to 3,500 times its normal intensity, allowing precise control over heat exposure.

Compared to the $100,000-per-day cost of arc jet testing and the $150,000-per-day cost of laser testing, solar testing costs about $25,000 per day, Armijo noted. The intensity of sunlight can be adjusted by varying the number of heliostats focused on the sample, mimicking different reentry conditions. NASA’s lead engineer for the Sample Retrieval Lander’s heat shield, Brandon Smith, commented, “Sandia’s ability to test at this size nicely complements our other test facilities.”

Testing also supports NASA’s Dragonfly mission to Titan, Saturn’s largest moon, with heat shield materials made from Phenolic Impregnated Carbon Ablator, developed at NASA’s Ames Research Center. Previously used in missions like Stardust and Mars 2020, the material was tested on two-foot-wide samples at Sandia. The facility’s capability to test larger samples allowed NASA to simulate the stress and strain experienced during atmospheric entry.

Dragonfly, a rotorcraft designed to explore Titan’s methane-rich atmosphere, faces unique challenges due to Titan’s dense atmosphere, which is four times thicker than Earth’s. To recreate the thermal conditions of Martian and Titan atmospheric entry, nitrogen gas is blown over the heat shield samples during tests. A newly installed gas line running from the base to the top of the power tower ensures adequate gas flow, said Armijo.

Daniel Ray, a mechanical technologist at Sandia, was responsible for setting up the gas line and addressing issues during tests. “My role on every project is to make it work,” Ray said. He resolved an issue with the carbon felt catching fire by designing ceramic shields to protect the system.

In 2022, Sandia also supported the Applied Physics Laboratory’s tests on a heat exchanger prototype intended for future spacecraft. The prototype endured light levels equivalent to 2,000 suns, reaching temperatures of 3,100 degrees Fahrenheit, demonstrating its ability to withstand the intense heat of a close solar flyby.

The facility’s history includes various aerospace projects, such as testing radar protection domes and evaluating materials for space shuttles and military aircraft. Sandia has refined its solar testing methods over the years, said Armijo. “Because we can dial-in the profiles, we have more confidence that it’s going to survive and function well during a mission. Having confidence that it will make it to Mars, land and pick up the rocks safely is important.”

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Solar Energy

Computer simulations offer new insights into enhancing solar cell materials

Published

2 days ago

October 16, 2024

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Computer simulations offer new insights into enhancing solar cell materials

by Robert Schreiber

Berlin, Germany (SPX) Oct 16, 2024

Researchers from Chalmers University of Technology in Sweden have made progress in understanding halide perovskites, a promising class of materials for solar cells. These materials could serve as an efficient and cost-effective alternative to traditional silicon-based cells, but they face challenges with stability. The new insights are expected to aid the development of more reliable and efficient solar cells, key components in the transition to sustainable energy.

Halide perovskites refer to a group of materials recognized for their potential in flexible, lightweight solar cells and various optical applications, such as LEDs. They exhibit high efficiency in light absorption and emission, making them suitable for next-generation solar technologies. However, understanding the causes of rapid degradation remains a hurdle in optimizing these materials.

Advanced computer simulations reveal material behavior

The research team employed advanced computer simulations and machine learning to study 2D perovskite materials, which are typically more stable than their 3D counterparts. The findings, published in *ACS Energy Letters*, provide new insights into the factors that influence the materials’ properties.

“By mapping out the material in computer simulations and subjecting it to different scenarios, we can draw conclusions about how the atoms in the material react when exposed to heat, light, and so on,” explained Professor Paul Erhart from the research team. “We now have a microscopic description of the material that is independent of what experiments have shown, but which we can show to lead to the same behavior as the experiments.”

Simulations allow researchers to analyze material behaviors at a detailed level, offering a unique view that complements experimental data. This approach has made it possible to observe what leads to specific outcomes in experiments, deepening the understanding of 2D perovskites’ functionality.

Machine learning enables broader and deeper analysis

The integration of machine learning techniques allowed the researchers to study larger systems over longer durations than was previously feasible.

“This has given us both a much broader overview than before, but also the ability to study materials in much more detail,” said Associate Professor Julia Wiktor. “We can see that in these very thin layers of material, each layer behaves differently, and that’s something that is very difficult to detect experimentally.”

The composition and interaction of layers in 2D perovskites

2D perovskites consist of inorganic layers separated by organic molecules, which play a crucial role in determining the material’s stability and optical properties. Understanding the atomic movements within these layers and their connection to the organic linkers is essential for designing efficient devices.

“In 2D perovskites, you have perovskite layers linked with organic molecules. What we have discovered is that you can directly control how atoms in the surface layers move through the choice of the organic linkers,” noted Erhart. “This movement is crucial to the optical properties, creating a domino effect that extends deep inside the material.”

Future research directions

The study’s results pave the way for developing more stable and efficient optoelectronic devices by identifying which molecular configurations could enhance performance. The researchers aim to extend their work to more complex systems, focusing on interfaces that are essential for device functionality.

“Our next step is to move to even more complex systems and in particular interfaces that are fundamental for the function of devices,” Wiktor added.

Research Report:Impact of Organic Spacers and Dimensionality on Templating of Halide Perovskites

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Solar Energy

Bright future for solar panels and screens with new nanocrystal research

Published

2 days ago

October 16, 2024

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Bright future for solar panels and screens with new nanocrystal research

by Simon Mansfield

Sydney, Australia (SPX) Oct 16, 2024

Curtin University researchers have made a significant discovery that could enhance everyday technology, from TV screens to solar panels and medical diagnostics. The study, led by Associate Professor Guohua Jia, revealed how to increase the number of molecules, known as ligands, that adhere to zinc sulfide nanocrystals by manipulating the shape of these tiny particles.

Associate Professor Jia from Curtin’s School of Molecular and Life Sciences explained that ligands are essential for influencing the behavior and performance of zinc sulfide nanocrystals across various applications. “Ligands play an important role in controlling the behaviour and performance of zinc sulfide nanocrystals in various important technologies,” Jia said.

The research found that flatter, more uniform particles, termed nanoplatelets, can accommodate a greater number of tightly bound ligands compared to other shapes such as nanodots and nanorods. “In a discovery that could open new possibilities for developing smarter, more advanced devices, our study found flatter, more even particles called nanoplatelets allow more ligands to attach tightly, compared to other shapes like nanodots and nanorods,” Jia explained.

By tailoring the shapes of these nanocrystals, the researchers were able to enhance their interactions with surrounding environments, boosting the efficiency of a wide range of applications. Jia highlighted that these findings could potentially transform the efficiency and performance of products such as LED lights, screens, solar panels, and medical imaging devices.

The discovery also holds promise for advancing optoelectronic devices, which either generate light or utilize it to perform various functions. “Optoelectronics are important in many modern technologies, including telecommunications, medical devices and energy production,” Jia noted. The ability to control the manipulation of light and electricity is vital for the development of faster, more efficient, and compact electronic systems.

The applications include LEDs used in light bulbs and TV screens, solar cells that convert sunlight into electrical power, photodetectors in cameras and sensors, and laser diodes in fiber-optic communication systems.

Research Report:Deciphering surface ligand density of colloidal semiconductor nanocrystals: Shape matters