Lifeboat Foundation

Stacking solar cells increases their efficiency. Working with partners in the PERCISTAND project, researchers at the Karlsruhe Institute of Technology (KIT) have produced perovskite/CIS tandem solar cells with an efficiency of nearly 25%—the highest value achieved thus far with this technology. Moreover, this combination of materials is light and versatile, making it possible to envision the use of these tandem solar cells in vehicles, portable equipment, and devices that can be folded or rolled up. The researchers present their results in the journal ACS Energy Letters.

Perovskite solar cells have made astounding progress over the past decade. Their efficiency is now comparable to that of the long-established silicon solar cells. Perovskites are innovative materials with a special crystal structure. Researchers worldwide are working to get perovskite photovoltaic technology ready for practical applications. The more electricity they generate per unit of surface area, the more attractive solar cells are for consumers.

The efficiency of solar cells can be increased by stacking two or more cells. If each of the stacked solar cells is especially efficient at absorbing light from a different part of the solar spectrum, inherent losses can be reduced and efficiency boosted. The efficiency is a measure of how much of the incident light is converted into electricity. Thanks to their versatility, perovskite solar cells make outstanding components for such tandems. Tandem solar cells using perovskites and silicon have reached a record efficiency level of over 29%, considerably higher than that of individual cells made of perovskite (25.7%) or silicon (26.7%).

New research suggests that Darwinian evolution could be happening up to four times faster than previously thought, based on an analysis of genetic variation.

The more genetic differences there are in a species, the faster evolution can happen, as certain traits die off and stronger ones get established. The team behind this latest study calls it the “fuel of evolution”, and they looked at data on 19 different wild animal groups around the world.

That data analysis revealed this raw material for evolution is more abundant than earlier estimates, and as a result we may have to adjust our expectations for how quickly animals evolve – a pertinent question in our age of climate change.

Chopping down trees and processing the wood isn’t the most efficient or environmentally friendly way to make furniture or building materials. Scientists at MIT have now made breakthroughs in a process that could one day let us 3D print and grow wood directly into the shape of furniture and other objects.

Wood may be a renewable resource, but we’re using it up much faster than we’re replenishing it. Deforestation is having a drastic impact on wildlife and exacerbating the effects of climate change. Since our appetite for wooden products isn’t likely to change, our methods for obtaining it will have to.

In recent years, researchers have turned to growing wood in the lab. Not trees – just the wood itself, not unlike the ongoing work into cultivating animal cells for lab-grown meat, rather than raising live animals and slaughtering them. And now, a team of MIT scientists has demonstrated a new technique that can grow wood-like plant material in the lab, allowing for easy tuning of properties like weight and strength as needed.

Whether or not a solid can emit light, for instance as a light-emitting diode (LED), depends on the energy levels of the electrons in its crystalline lattice. An international team of researchers led by University of Oldenburg physicists Dr. Hangyong Shan and Prof. Dr. Christian Schneider has succeeded in manipulating the energy-levels in an ultra-thin sample of the semiconductor tungsten diselenide in such a way that this material, which normally has a low luminescence yield, began to glow. The team has now published an article on its research in the science journal Nature Communications.

According to the researchers, their findings constitute a first step towards controlling the properties of matter through light fields. “The idea has been discussed for years, but had not yet been convincingly implemented,” said Schneider. The light effect could be used to optimize the optical properties of semiconductors and thus contribute to the development of innovative LEDs, solar cells, optical components and other applications. In particular the optical properties of organic semiconductors—plastics with semiconducting properties that are used in flexible displays and solar cells or as sensors in textiles—could be enhanced in this way.

Tungsten diselenide belongs to an unusual class of semiconductors consisting of a transition metal and one of the three elements sulfur, selenium or tellurium. For their experiments the researchers used a sample that consisted of a single crystalline layer of tungsten and selenium atoms with a sandwich-like structure. In physics, such materials, which are only a few atoms thick, are also known as two-dimensional (2D) materials. They often have unusual properties because the charge carriers they contain behave in a completely different manner to those in thicker solids and are sometimes referred to as “quantum materials.”

Some things that could make the world more efficient simply feel impossible to achieve — not like having to eat and sleep or not suffering through inflated grocery store prices.

Earlier this week, though, scientists at UC Riverside and the University of Delaware say they found a way to cross one of those seemingly impossible barriers when they convinced plants to grow in total darkness. A university press release says the team used a two-step process to convert carbon dioxide, electricity and water into acetate. Plants consumed the acetate and were able to grow in the dark.

The release said that combined with solar panels to generate electricity, this method of food production would be more than 18 times as effective as the natural process, which they claim uses only 1 percent of the energy found in sunlight alone. The team’s research was published Thursday in the journal Nature Food.

Climate change is already had a serious impact on global food production — from making food less nutritious to messing with the growing season of plants, to even pushing some crop species towards extinction. On top of that, the world’s oceans are already stressed by overfishing, with over 70 percent of the world’s fish stocks fully exploited, over-exploited, or depleted.

The combination of overuse and climate change could prove deadly for global food security. And by the time 2,300 rolls around, it will be too late to mitigate the impact of human activity on our food sources, both those on land and those under the sea.

Yet another startup says it’s nearing tests for a system that could once and for all prove the technology can actually generate more energy than it consumes, The New York Times reports.

Seattle-based startup Zap Energy says its approach to fusion energy — potentially an entirely green source of renewable energy — is far simpler and cheaper than other attempts.

But critics are crying foul, arguing that we’re merely stuck in yet another round of “fusion energy fever,” according to the report.

Now look out past the sun, way beyond. Most of the stars harbor planets of their own. Astronomers have spotted thousands of these distant star-and-planet systems. But strangely, they have so far found none that remotely resemble ours. So the puzzle has grown harder: Why these, and why those?

The swelling catalog of extrasolar planets, along with observations of distant, dusty planet nurseries and even new data from our own solar system, no longer matches classic theories about how planets are made. Planetary scientists, forced to abandon decades-old models, now realize there may not be a grand unified theory of world-making—no single story that explains every planet around every star, or even the wildly divergent orbs orbiting our sun. “The laws of physics are the same everywhere, but the process of building planets is sufficiently complicated that the system becomes chaotic,” said Alessandro Morbidelli, a leading figure in planetary formation and migration theories and an astronomer at the Côte d’Azur Observatory in Nice, France.

Still, the findings are animating new research. Amid the chaos of world-building, patterns have emerged, leading astronomers toward powerful new ideas. Teams of researchers are working out the rules of dust and pebble assembly and how planets move once they coalesce. Fierce debate rages over the timing of each step, and over which factors determine a budding planet’s destiny. At the nexus of these debates are some of the oldest questions humans have asked ourselves: How did we get here? Is there anywhere else like here?

Alex SharpThe world needs to be subsidising heat pumps for the poorer regions of the world, to keep people safe.

2 Replies.

Chris BartlettThat’s alarmist, while they’re is global warming, there’s little evidence that we are yet seeing extreme weather previously unseen in Earth’s history or even during human history.

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