Lifeboat Foundation

Researchers have developed a new type of high-efficiency photodetector inspired by the photosynthetic complexes plants use to turn sunlight into energy. Photodetectors are used in cameras, optical communication systems and many other applications to turn photons into electrical signals.

Researchers developed a new type of high-efficiency photodetector that is similar to the photosynthetic complexes plants use to turn sunlight into energy. The new design integrates a simple organic detector into the propagation region to produce efficient polariton-to-charge conversion over distances of up to 100 microns. (Image: Bin Liu, University of Michigan)

“Our devices combine long-range transport of optical energy with long-range conversion to electrical current,” said research team leader Stephen Forrest from the University of Michigan. “This arrangement, analogous to what is seen in plants, has the potential to greatly enhance the power generation efficiency of solar cells, which use devices similar to photodetectors to convert sunlight into energy.”

Solar cell manufacturing just became easier, more efficient, and less costly. A team of researchers at DOE’s Lawrence Berkeley National Laboratory (Berkeley Lab), in collaboration with UC Berkeley, has discovered a unique material that can be used as a simpler approach to solar cell manufacturing, the team reported.

This material is a crystalline solar material with a built-in electric field — also known as “ferroelectricity” — that was reported earlier this year in the journal Science Advances.

Light microscopy image of nanowires, 100 to 1,000 nanometers in diameter, grown from cesium germanium tribromide (CGB) on a mica substrate. The CGB nanowires are samples of a new lead-free halide perovskite solar material that is also ferroelectric. (Credit: Peidong Yang and Ye Zhang/Berkeley Lab)

Continue reading “Scientists Grow Lead-Free Solar Material With a Built-In Switch” »

Proposals for beaming solar power down from space have been around since the 1970s, but the idea has long been seen as little more than science fiction. Now, though, Europe seems to be getting serious about making it a reality.

Space-based solar power (SBSP) involves building massive arrays of solar panels in orbit to collect sunlight and then beaming the collected energy back down to Earth via microwaves or high-powered lasers. The approach has several advantages over terrestrial solar power, including the absence of night and inclement weather and the lack of an atmosphere to attenuate the light from the sun.

But the engineering challenge involved in building such large structures in space, and the complexities of the technologies involved, have meant the idea has remained on the drawing board so far. The director general of the European Space Agency, Josef Aschbacher, wants to change that.

In 2021, scientists published a feasibility study about erecting solar panels over canals, and it’s about to become a reality.

Plants use light waves from only a portion of the spectrum for photosynthesis—the remainder can be recovered and used to generate solar power. That’s the idea behind the solar modules developed by EPFL startup Voltiris. Following encouraging preliminary results, a new pilot installation was recently installed in Graubünden.

In Switzerland, growing tomatoes, cucumbers, peppers and other light-and heat-intensive vegetables requires building a greenhouse—but operating one consumes a huge amount of power. Farmers have to carefully balance crop yields and economics with environmental concerns. “It costs more than CHF 1.5 million a year to heat a 5-hectare greenhouse,” says Nicolas Weber, the CEO of Voltiris. “And a greenhouse of that size emits roughly the same amount of CO₂ per year as 2,000 people.”

The Swiss federation of fruit & vegetable growers, which cultivate several thousand hectares across the country, has set a target of eliminating all fossil-fuel-based energy from its farming processes by 2040. The system developed by Voltiris can go a long way towards reaching that goal. Its technology is based on the fact that plants don’t use all of the waves contained in sunlight; the remaining ones can be concentrated onto photovoltaic (PV) cells to generate solar power. Voltiris’ system is lightweight and designed to track the sun’s movement across the sky, and boasts daily yields on par with conventional solar panels. The first vegetables grown under Voltiris’ system were harvested this summer through pilot tests carried out at two greenhouses, in the cantons of Valais and Graubünden.

99 percent of the panels were made of PET.

Do you remember the solar panels that Prof. Paul Dastoor from the University of New Castle and his team produced with a 3D printer? If you don’t, it’s an evergreen story worth remembering. Let’s dive in…

Continue reading “3D-printed solar cells are cheaper, easier to produce, and deployable at speed” »

Clean water is essential for human survival. However, less than 3% of fresh water can be used as drinking water. According to a report published by the World Meteorological Organization, there is scarcity of drinking water for approximately 1 billion people worldwide, which is expected to rise to 1.4 billion by 2050.

Seawater desalination technology, which produces fresh water from seawater, could solve the problem of water scarcity. At the Korea Institute of Science and Technology (KIST), a research team led by Dr. Kyung Guen Song from the Center for Water Cycle Research, have developed a hybrid membrane distillation module that combines solar energy with hydrothermal heat pumps to reduce thermal energy consumption during the desalination process. Their results are published in Energy Conversion and Management.

Reverse osmosis and evaporation methods are relatively common seawater desalination processes; however, these methods can operate only at high pressures and temperatures. In comparison, the membrane distillation method produces fresh water by utilizing the vapor pressure generated by the temperature difference between the flowing raw water and treated water separated by a membrane. This approach has the advantage of low energy consumption, as fresh water can be generated at pressures of 0.2–0.8 bar, which is lower than atmospheric pressure, and temperatures of 50–60℃. However, large scale operation requires more thermal energy. Thus, research studies are required to reduce the use of thermal energy for commercial operation.

Solar cells are vital for the green energy transition. They can be used not only on rooftops and solar farms but also for powering autonomous vehicles, such as planes and satellites. However, photovoltaic solar cells are currently heavy and bulky, making them difficult to transport to remote locations off-grid, where they are much needed.

In a collaboration led by Imperial College London, alongside researchers from Cambridge, UCL, Oxford, Helmholtz-Zentrum Berlin in Germany, and others, researchers have produced materials that can absorb comparable levels of sunlight as conventional silicon solar cells, but with 10,000 times lower thickness.

The material is sodium bismuth sulfide (NaBiS₂), which is grown as nanocrystals and deposited from solution to make films 30 nanometers in thickness. NaBiS₂ is comprised of nontoxic elements that are sufficiently abundant in the earth’s crust for use commercially. For example, bismuth-based compounds are used as a nontoxic lead replacement in solder, or in over-the-counter stomach medicine.

As the world builds out ever larger installations of wind and solar power systems, the need is growing fast for economical, large-scale backup systems to provide power when the sun is down and the air is calm. Today’s lithium-ion batteries are still too expensive for most such applications, and other options such as pumped hydro require specific topography that’s not always available.

Now, researchers at MIT and elsewhere have developed a new kind of battery, made entirely from abundant and inexpensive materials, that could help to fill that gap.

The new battery architecture, which uses aluminum and sulfur as its two electrode materials, with a molten salt electrolyte in between, is described today in the journal Nature, in a paper by MIT Professor Donald Sadoway, along with 15 others at MIT and in China, Canada, Kentucky, and Tennessee.