Lifeboat Foundation

Thin films of crystalline materials called perovskites provide a promising new way of making inexpensive and efficient solar cells. Now, an international team of researchers has shown a way of flipping a chemical switch that converts one type of perovskite into another—a type that has better thermal stability and is a better light absorber.

The study, by researchers from Brown University, the National Renewable Energy Laboratory (NREL) and the Chinese Academy of Sciences’ Qingdao Institute of Bioenergy and Bioprocess Technology published in the Journal of the American Chemical Society, could be one more step toward bringing perovskite solar cells to the mass market.

“We’ve demonstrated a new procedure for making solar cells that can be more stable at moderate temperatures than the perovskite solar cells that most people are making currently,” said Nitin Padture, professor in Brown’s School of Engineering, director of Brown’s Institute for Molecular and Nanoscale Innovation, and the senior co-author of the new paper. “The technique is simple and has the potential to be scaled up, which overcomes a real bottleneck in perovskite research at the moment.”

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(Phys.org)—For the past 17 years, spiro-OMeTAD, has been keeping a secret. Despite intense research efforts, its performance as the most commonly used hole-transporting material in perovskite and dye-sensitized solar cells has remained stagnant, creating a major bottleneck for improving solar cell efficiency. Thinking that the material has given all it has to offer, many researchers have begun investigating alternative materials to replace spiro-OMeTAD in future solar cells.

But in a new study published in Science Advances, Dong Shi et al. have taken a closer look at spiro-OMeTAD and found that it still has a great deal of untapped potential. For the first time, they have grown single crystals of the pure material, and in doing so, they have made the surprising discovery that spiro-OMeTAD’s single-crystal structure has a hole mobility that is three orders of magnitude greater than that of its thin-film form (which is currently used in solar cells).

“This paper reports a major breakthrough for the fields of perovskite and solid-state dye-sensitized solar cells by finally clarifying the potential performance of the material and showing that improving the crystallinity of the hole transport layer is the key strategy for further breakthroughs in device engineering of these solar cells,” Osman Bakr, a professor of engineering at King Abdullah University of Science and Technology (KAUST) in Saudi Arabia and leader of the study, told Phys.org.

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Tech capital is first major US city to require all new buildings of 10 storeys or under to have solar panels, reports BusinessGreen.

The researchers call their material a hybrid because they dope the electrical conductivity of layered tin disulfide semiconductor with the light harvesting of different spectrums of light from various sized quantum dots.

SolaBat is developing a hybrid device that utilizes both solar cells and more traditional electrochemical energy storage systems.

Last month, the Austrian Research Promotion Agency (FFG) announced a groundbreaking new project called SolaBat. Spearheaded by a group of researchers at the Graz University of Technology (TU Graz) led by Illie Hanzu, it aims to combine photovoltaic cells and electrochemical energy storage systems into a single hybrid device. Fundamentally, SolaBat plans to create a more simplified system of converting and storing solar power.

“Currently, single systems of photovoltaic cells which are connected together – mostly lead-based batteries and vast amounts of cable – are in use. Solar panels on the roof with a battery in the cellar. This takes up a lot of space, needs frequent maintenance and is not optimally efficient,” says Hanzu. “We want to make a battery and solar cell hybrid out of two single systems which is not only able to convert electrical energy but also store it.”

The Space Solar Power Initiative (SSPI), a collaboration between Caltech and Northrup Grumman, has developed a system of lightweight solar power tiles which can convert solar energy to radio waves and can be placed in orbit to beam power to an energy-thirsty Earth.

One of the greatest challenges facing the 21st Century is the issue of power—how to generate enough of it, how to manufacture it cheaply and with the least amount of harmful side-effects, and how to get it to users.

The solutions will have to be very creative—rather like what the Space Solar Power Initiative (SSPI), a partnership between Caltech and Northrup Grumman, has devised.

Continue reading “Caltech’s 2500 Orbiting Solar Panels Could Provide Earth With Limitless Energy” »

A ‘brane’ is a dynamical object that can propagate through spacetime. Flattening a spacecraft into a membrane, or 2-brane, can produce a low mass vehicle with ultra-high power-to-weight ratio (7.7 kW/kg using thin film solar cells). If most of this power is used by an array of thinned, distributed electrospray thrusters with a specific impulse of 4000 s, a Brane Craft could start in low Earth orbit, land on Phobos, and return to low Earth orbit.

Other possible targets include any near-Earth asteroid and most main belt asteroids. Propellant is stored as a liquid within a 10-micron wide gap between two Kapton sheets that form the main structure of the Brane Craft.

This NASA NIAC project will study how to design an ultra-light dynamic membrane spacecraft, with 3-axis attitude determination and control plus navigation, that can significantly change both its shape and orbit. Conventional sensors like star trackers will have to be replaced by 2-dimensional alternatives. Estimated mass is about 35 grams for a 1 square meter Brane Craft.

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Luv it — Improving Solar energy with Quantum.

A quantum process called singlet fission could boost solar cell efficiency by harnessing inaccessible parts of the solar spectrum.

Solar power is making huge strides as a reliable, renewable energy source, but there’s still a lot of untapped potential in terms of the efficiency of photovoltaic cells and what happens at night and during inclement weather. Now a solution has been put forward in the form of producing energy from raindrops.

Key to the new process is graphene: a ‘wonder’ material we’ve heard plenty about before. Because raindrops are not made up of pure water, and contain various salts that split up into positive and negative ions, a team from the Ocean University of China in Qingdao thinks we can harness power via a simple chemical reaction. Specifically, they want to use graphene sheets to separate the positively charged ions in rain (including sodium, calcium, and ammonium) and in turn generate electricity.

Early tests, using slightly salty water to simulate rain, have been promising: the researchers were able to generate hundreds of microvolts and achieve a respectable 6.53 percent solar-to-electric conversion efficiency from their customised solar panel.

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