We convert the sun‘s heat to electricity, but if we learn to store it in chemical form, it is advantageous. This is because it can be stored for a long period of time   without losing any of the stored energy.

Until now, the chemicals needed for this storage often degraded within a few cycles, or included an expensive and rare element called ruthenium.

However, last year, MIT associate professor Jeffrey Grossman and four co-authors solved how to use diruthenium, the top chemical for reversibly storing solar energy, to store this. This made it easier to understand the process and see which materials could be used this way.

Now, Grossman and fellow researcher Alexie Kolpak have solved how to do this. The duo used carbon nanotubes, small tubular structures of pure carbon, along with a compound called azobenzene. The resulting molecules were produced using nanoscale templates to control their physical structure and find new properties in the separate materials.

This new chemical system is less expensive than earlier options, as well as more efficient at storing energy.  These nanofabrication methods can control the molecules’ interactions, increasing the amount of stored energy, the length of time they can store it, with total, independent control.

This type of solar energy uses a molecule that changes structure when exposed to sunlight. It can forever remain stable in that form until a stimulus can quickly bring it back to its other form. This releases its stored energy in a burst of heat. This works similarly to a rechargeable battery.

An advantage of this new approach it combines energy harvesting and storage into a single step. This makes it much simpler. A limitation, however, is that while this can be used for heating, producing electricity would require an extra step.

The team is “very actively looking at a range of new materials,” Grossman says, and calls this the “tip of the iceberg.”

Yosuke Kanai, assistant professor of chemistry at the University of North Carolina at Chapel Hill, says “the idea of reversibly storing solar energy in chemical bonds is gaining a lot of attention these days. The novelty of this work is how these authors have shown that the energy density can be significantly increased by using carbon nanotubes as nanoscale templates. This innovative idea also opens up an interesting avenue for tailoring already-known photoactive molecules for solar thermal fuels and storage in general.”

The team’s success is outlined in a paper with their new findings published online in the journal Nano Letters.

Read more from ScienceDaily.

These stars, NGC 3603 and RMC 136a, were explored in detail. NGC 3603, located 22000 light-years away from the Sun, is a cosmic factory where stars form extended clouds of gas and dust. RMC 136a is located inside the Tarantula Nebula, in a neighbouring galaxy, the Large Magellanic Cloud, 165 000 light-years away.

The team found that the surface temperatures of many of these stars was over 40 000 degrees, which is seven times hotter than the Sun. They were also tens of times larger and several million times brighter.The star R136a1, found in the R136 cluster, is largest star ever found.

“Unlike humans, these stars are born heavy and lose weight as they age,” explains Paul Crowther. “Being a little over a million years old, the most extreme star R136a1 is already ‘middle-aged’ and has undergone an intense weight loss programme, shedding a fifth of its initial mass over that time, or more than fifty solar masses.”

He continues: “[The R136's] high mass would reduce the length of the Earth’s year to three weeks, and it would bathe the Earth in incredibly intense ultraviolet radiation, rendering life on our planet impossible,” says Raphael Hirschi from Keele University, who belongs to the team.

These rare stars keep the researchers puzzled; theorists, however, want to continue to explore the challenges to determine what makes them what they are, and how they form.

Not only is R136a1 the most massive star that has been discovered, but also the brightest, close to 10 million times greater than the Sun. “Owing to the rarity of these monsters, I think it is unlikely that this new record will be broken any time soon,” Crowther says.

For the full article, see Science Daily.

Image courtesy from apod.nasa.gov

The SFGate recently reported that students and professors at San Jose State University have created the ZEM (meaning Zero Emissions), a human, solar and electrical powered vehicle.

Led by Tai-Ran Hsu, a team of 72 students took three years to develop a green vehicle that wouldn’t also overly consume electricity.

“If today we converted all gasoline-powered to electric cars, it would consume more electricity than the utilities can produce,” Hsu told the SFGate. “The whole idea of this vehicle is trying to mitigate the use of electricity by supplementing the electricity with a renewable source like solar power or human power,” he added.

The ZEM isn’t just electric; it also has four solar panels, as well as a motor that can be powered on silicone batteries, chargeable by standard household outlets. These silicone batteries take less energy to change than run-of-the-mill alkaline varieties.

But that’s not all. The ZEM can also be powered by humans, with a set of bicycle pedals for the driver and the passenger – perfect for a little afternoon exercise or if your battery runs out of juice.

The ZEM was awarded first prize in the 2007 national idea-to-product competition, winning $15,000. The vehicle cost about $80,000 to make.

Read the full article here.

Image: ZEM, courtesy of SFGate

SunCatcher’s Solar Powered Golf Cart Panels make you wonder why someone didn’t think of it sooner. The batteries recharge as you play, extending the life of your electric golf cart.

The upside is you don’t have to go out and buy a whole new cart – SunCatcher’s panels can easily be installed on all major golf cart brands for a steady charge during your game. The panels are installed on the cart’s roof and add juice to the cart’s internal batteries while you’re on the green.

The panels are easy to install and maintenance-free, and come with a  controller to prevent batteries from being overcharged by the sun on those longer days when you play an extra round.

So what about on overcast days? They seem to have it covered. SunCatcher’s system operates and provides a constant charge even in poor weather. And because they recharge a third faster and use a third less energy, there is no need to have double the supply of golf carts when half of them are plugged in to refill for the next round.

suncatchergolf.com