Just a few years ago, low cost natural gas was the main force pushing coal out of the power generation market, and now low cost solar power is sneaking up on low cost natural gas. So far the competition is a trickle, not a flood. However, natural gas stakeholders don’t have much breathing room left, as indicated by the latest perovskite solar cell research.
We are closer to being able to build a Dyson Sphere than we think. By enveloping the sun in a massive sphere of artificial habitats and solar panels, a Dyson Sphere would provide us with more energy than we would ever know what to do with while dramatically increasing our living space. Implausible you say? Something for our distant descendants to consider? Think again. We could conceivably get going on the project in about 25 to 50 years, with completion of the first phase requiring only a few decades.
(Nanowerk News) Scientists in Australia and the United States have been able to ‘upconvert’ low energy light into high energy light, which can be captured by solar cells, in a new way, with oxygen the surprise secret ingredient. The results are published in Nature Photonics (“Photochemical upconversion of near-infrared light from below the silicon bandgap”).
Scientists in Australia and the United States have been able to ‘upconvert’ low energy light into high energy light, which can be captured by solar cells, in a new way, with oxygen the surprise secret ingredient.
The results are published in Nature Photonics (“Photochemical upconversion of near-infrared light from below the silicon bandgap”).
While the approach’s efficiencies are relatively low and more work is needed to achieve commercialisation, the research is an exciting development, according to senior author Professor Tim Schmidt from the ARC Centre of Excellence in Exciton Science and UNSW Sydney.
“The energy from the sun is not just visible light,” Prof. Schmidt explains.
Engineers have developed a new type of hybrid solar energy converter, which uses energy from the Sun to create both electricity and steam. The device reportedly has high efficiency and runs at low cost, allowing industry to make use of a wider spectrum of solar energy.
The most common way of collecting energy from the Sun is through photovoltaics. These solar cells produce electricity from sunlight, and they’re so simple that they’re built into everything from garden lights to the grid itself.
But it’s not the only way. Solar concentrators collect heat instead of light, focusing the Sun’s rays to heat up a contained fluid. This can then be used to generate electricity – say as steam turning a turbine – or more directly, to heat homes or for other industrial processes.
Circa 2012
Big science meets applied engineering. CERN, renowned for smashing protons, culling antimatter and the like, has put its accelerating processes to use making and commercializing solar panels.
Chemists at the University of Wisconsin-Madison and their collaborators have created a highly efficient and long-lasting solar flow battery, a way to generate, store and redeliver renewable electricity from the sun in one device.
The new device is made of silicon solar cells combined with advanced solar materials integrated with optimally designed chemical components. The solar flow battery, made by the Song Jin lab in the UW-Madison chemistry department, achieved a new record efficiency of 20 percent. That bests most commercially available silicon solar cells used today and is 40 percent more efficient than the previous record holder for solar flow batteries, also developed by the Jin lab.
Scientists have made a battery that can be directly charged in sunlight without needing an external solar panel. Clever design of the battery electrodes facilitates photo-rechargeable zinc-ion batteries that could find applications as cheap devices for off-grid solar farms.
Solar energy is often stored in rechargeable batteries for later use. Currently, this process requires separate solar cells to harvest the energy, and batteries to store it. Now, a team led by Michael De Volder from the University of Cambridge in the UK has engineered a battery cathode that can take the place of the solar cell and recharge the battery without requring an external energy harvester.
Spiders produce amazingly strong and lightweight threads called draglines that are made from silk proteins. Although they can be used to manufacture a number of useful materials, getting enough of the protein is difficult because only a small amount can be produced by each tiny spider. In a new study published in Communications Biology, a research team led by Keiji Numata at the RIKEN Center for Sustainable Resource Science (CSRS) reported that they succeeded in producing the spider silk using photosynthetic bacteria. This study could open a new era in which photosynthetic bio-factories stably output the bulk of spider silk.
In addition to being tough and lightweight, silks derived from arthropod species are biodegradable and biocompatible. In particular, spider silk is ultra-lightweight and is as tough as steel. “Spider silk has the potential to be used in the manufacture of high-performance and durable materials such as tear-resistant clothing, automobile parts, and aerospace components,” explains Choon Pin Foong, who conducted this study. “Its biocompatibility makes it safe for use in biomedical applications such as drug delivery systems, implant devices, and scaffolds for tissue engineering.” Because only a trace amount can be obtained from one spider, and because breeding large numbers of spiders is difficult, attempts have been made to produce artificial spider silk in a variety of species.
The CSRS team focused on the marine photosynthetic bacterium Rhodovulum sulfidophilum. This bacterium is ideal for establishing a sustainable bio-factory because it grows in seawater, requires carbon dioxide and nitrogen in the atmosphere, and uses solar energy, all of which are abundant and inexhaustible.
Solar cells based on perovskite compounds could soon make electricity generation from sunlight even more efficient and cheaper. The laboratory efficiency of these perovskite solar cells already exceeds that of the well-known silicon solar cells. An international team led by Stefan Weber from the Max Planck Institute for Polymer Research in Mainz has found microscopic structures in perovskite crystals that can guide the charge transport in the solar cell. Clever alignment of these electron highways could make perovskite solar cells even more powerful.
When solar cells convert sunlight into electricity, the electrons of the material inside the cell absorb the energy of the light. Traditionally, this light-absorbing material is silicon, but perovskites could prove to be a cheaper alternative. The electrons excited by the sunlight are collected by special contacts on the top and bottom of the cell. However, if the electrons remain in the material for too long, they can lose their energy again. To minimize losses, they should therefore reach the contacts as quickly as possible.
Microscopically small structures in the perovskites—so-called ferroelastic twin domains—could be helpful in this respect: They can influence how fast the electrons move. An international research group led by Stefan Weber at the Max Planck Institute for Polymer Research in Mainz discovered this phenomenon. The stripe-shaped structures that the scientists investigated form spontaneously during the fabrication of the perovskite by mechanical stress in the material. By combining two microscopy methods, the researchers were able to show that electrons move much faster parallel to the stripes than perpendicular to them. “The domains act as tiny highways for electrons,” compares Stefan Weber.
