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The fast developping solar cell technology of perovskites. "Perovskites are a broad class of crystalline minerals that have been known for well over a century. But their ability to convert solar energy to electricity came to light only in 2009. Since then, the efficiency of perovskite solar cells has climbed from 3.8% to 19.3%, a pace of improvement unmatched by any other solar technology. By comparison, crystalline silicon solar cells, the leading commercial technology, convert about 25% of solar energy to electricity."

The principle behind that is Nantenna.

this is fantastic!!!! waiting of somebody to make this happen since years The size of the gap is critical because it creates an ultra-fast tunnel junction between the rectenna's two electrodes, allowing a maximum transfer of electricity. The nanosized gap gives energized electrons on the rectenna just enough time to tunnel to the opposite electrode before their electrical current reverses and they try to go back. The triangular tip of the rectenna makes it hard for the electrons to reverse direction, thus capturing the energy and rectifying it to a unidirectional current. Impressively, the rectennas, because of their extremely small and fast tunnel diodes, are capable of converting solar radiation in the infrared region through the extremely fast and short wavelengths of visible light - something that has never been accomplished before. Silicon solar panels, by comparison, have a single band gap which, loosely speaking, allows the panel to convert electromagnetic radiation efficiently at only one small portion of the solar spectrum. The rectenna devices don't rely on a band gap and may be tuned to harvest light over the whole solar spectrum, creating maximum efficiency. Through atomic layer deposition, Willis has shown he is able to precisely coat the tip of the rectenna with layers of individual copper atoms until a gap of about 1.5 nanometers is achieved. The process is self-limiting and stops at 1.5 nanometer separation The size of the gap is critical because it creates an ultra-fast tunnel junction between the rectenna's two electrodes, allowing a maximum transfer of electricity. The nanosized gap gives energized electrons on the rectenna just enough time to tunnel to the opposite electrode before their electrical current reverses and they try to go back. The triangular tip of the rectenna makes it hard for the electrons to reverse direction, thus capturing the energy and rectifying it to a unidirectional current. Impressively, the rectennas, because of th

With the first ever production of synthesized "solar" jet fuel, the EU-funded SOLAR-JET project has successfully demonstrated the entire production chain for renewable kerosene obtained directly from sunlight, water and carbon dioxide (CO2), therein potentially revolutionizing the future of aviation. This process has also the potential to produce any other type of fuel for transport applications, such as diesel, gasoline or pure hydrogen in a more sustainable way.

Unexplained annual variations in nuclear decay rates have been reported in recent years by a number of groups. We show that data from these experiments exhibit not only variations in time related to Earth-Sun distance, but also periodicities attributable to solar rotation. Additionally, anomalous decay rates coincident in time with a series of solar flares in December 2006 also point to a solar influence on nuclear decay rates....

can we use space to make a smart experiment to solve this riddle? e.g. sending a decay detecter on a close solar orbit and one to Pluto and then compare decay rates? or a highly elliptical trajectory and compare during peri and apoapsis?

I think it could be possible. I need to look into the details. In fact it could probably be done already with the nuclear generators on the Voyager and Pioneer and other nuclear powered probes. That is if the data are precise enough...

Computer simulations by researchers in the US and China could lead to solar cells that work efficiently across a broad range of the solar spectrum.

doubt that this would work ...

Researchers in the US have built a new type of solar cell that emits light as well as absorbs it, making it the most efficient solar cell ever developed. The efficiency of their prototype cell allows it to convert 28.6% of the Sun's energy into electricity.

well, the text is at best misleading ... the most efficient solar cells are well over 35% and approach the 40s with concentration! what they have done is to increase the limit of a single junction cell it seems to me ... still, nteresting though from text most details on how this was done are missing ... paper is not yet published, correct?

I learn of it in a workshop few weaks ago. It's on GaAs and I think that the key theoretical aspects are explained here: http://arxiv.org/abs/1106.1603

Chemists at UCR have found a way of turning a single photon into two excitons, by a process known as singlet fission. By doubling the yield of excitons in a solar cell, you theoretically double the number of electrons produced and could lead to having a max theoretical efficiency of 60% or more in an (organic) solar cell See also DOI: 10.1021/jz500676c - "Singlet Fission: From Coherences to Kinetics"

A new manufacturing process could mean improved efficiency for solar cells. The technique, which is being pioneered by researchers at the University of California, San Diego, results in "hairy" solar cells.

TU/e is participating in the new Cruiser class of the World Solar Challenge. This competition entails building an eco friendly family car (instead of a racer) to prove that solar powered transportation is possible. Actually this car produces more solar power than it needs and has a range of 300+ km.

3-dimensional silicon solar cell produces at least 250% of the power of a basic silicon solar cell.

Any idea of the technology behind ... Sounds too much advertisement what is in the article " Now, our near term objective is to continue to improve the fabrication process and the power output, as we optimize the cost of manufacturing. We believe that the result will be a 50% reduction in the cost of solar electricity. Perhaps the installed system cost savings will be even greater"

A new discovery from a chemist at the University of Texas at Austin may allow photovoltaic solar cells to double their efficiency, thus providing loads more electrical power from regular sunlight.

instead of using the solar generated steam to generate electricity, it seems to make economic sense to use it to pump more oil out of the ground ...

Researchers at the University of Toronto in Canada and KAUST in Saudi Arabia have made a solar cell out of colloidal quantum dot (CQD) films that has a record-breaking efficiency of 7%. This is almost 40% more efficient than the best previous devices based on CQDs.

A fifth giant planet was kicked out of the early solar system, according to computer simulations by a US-based planetary scientist. The sacrifice of this gas giant paved the way for the stable configuration of planets seen today, says David Nesvorný, who believes that the expulsion prevented Jupiter from migrating inwards and scattering the Earth and its fellow inner planets.

A fifth giant planet was kicked out of the early solar system, according to computer simulations by a US-based planetary scientist. The sacrifice of this gas giant paved the way for the stable configuration of planets seen today, says David Nesvorný, who believes that the expulsion prevented Jupiter from migrating inwards and scattering the Earth and its fellow inner planets.

The enormous solar plant-jointly owned by NRG Energy, BrightSource Energy and Google-opened for business today ... well yesterday, but still impressive!

impressive pictures - looking at the 2nd to last and 4th to last one, I am wondering how this distributed individually control of the mirrors works - and idea?

Machine learning obviously. Most likely neural networks :P On the other hand: http://sploid.gizmodo.com/the-worlds-largest-solar-plant-is-killing-birds-meltin-1525107821

A 7x7x3m large unfolding structure from the car trunk. "Before the design is ready to roll, the team still needs to tune up the solar components, a challenge made more difficult by the pavilion's inherent mobility, making it impossible to gauge how sunlight will fall on it."

The work is based on the use of a "continuous flow" microreactor to produce nanoparticle inks that make solar cells by printing. In this process, simulated sunlight is focused on the solar microreactor to rapidly heat it, while allowing precise control of temperature to aid the quality of the finished product. The light in these experiments was produced artificially, but the process could be done with direct sunlight, and at a fraction of the cost of current approaches.

anybody interested in having a closer look at this?

Rings of excited atoms that harness a quantum effect to absorb light at an enhanced rate could be used in future technologies such as highly sensitive cameras, solar cells and systems for optical power transmission.

The Japan Aerospace Exploration Agency spacecraft Ikaros now represents the first solar sail to have harnessed sunlight for both attitude control and propulsion, after it first launched May 21 alongside the Venus-bound orbiter Akatsuki.