I am going to bet most people reading this know what a solar cell is, since the odds against you surfing the Internet but simultaneously not knowing about a technology that has existed since the 1950s (and was conceived in the 1800s) are pretty astronomical. To most of us, they are large shiny panels of black material that adorn roof tops or fields, and we know they soak up the sun and turn it into electricity.

Lucky for us, there are large number of folks in the world who have pretty wild imaginations and access to outside funding. As a result, Photovoltaics are not just limited to flat, boring cells collecting bird poop and marginally alleviating our reliance on fossil fuels. These concepts could one day elevate solar power to dominance as our primary source of power.

And if they don’t, hey, whatever, some of them at least look pretty cool.

Solar Windows

Photo credit: New Energy Technologies

Unless you work in a cave or a parking garage, odds are pretty good that the building you work in has windows. If you work in a major city, odds are even greater that the outside of your building is covered in glass, which does two things really well; let light through, and reflects quite a bit of it away.

The smart people at New Energy technologies, however, decided that just letting the light pass through the window was silly. Why waste all of that light heating the floor and blinding the accountants and IT guys four hours a day when you could capture some of it for free energy?

What they did was develop a solar cell so small it could just be sprayed on to a surface (more on that in a bit) and fine enough to not darken the glass significantly. They are developing everything from residential and commercial grade glass for homes and offices, to structural glass for big structures and art, Architectural glass for interior walls, even flexible films, similar to window clings. Except they turn a hot day into free air conditioning. If the numbers New Energy is showing on their site are accurate, their windows will actually collect energy better than normal solar cells. Those dreams of a greenhouse powered hot tub may become reality after all.

Solar Textiles

Photo Credit: MIT News

While we’re on the subject of things that are everywhere that could easily be drinking up the sun’s rays to power our portable heated thermos (assuming they have those), what about your clothes? One area that is being researched heavily is solar textiles, flexible, wearable solar cells that could mean a future where the drapes we pull closed behind our solar windows are also solar collectors.

One idea is to use the fabrics to drape over structures, using the same space that would hold normal solar panels in a more efficient, less jarring way. Or they could be woven into clothing, especially since e-textiles are becoming a hot commodity, to power the nifty new fashions or even wearable televisions some day.

Some clever folks are even using them to help people in developing nations to make a few extra bucks and otherwise better their lives by giving them solar textile kits and training on how to weave them into clothes. They can make everything from a purse that charges your cell phone to clothes that will allow them to read at night. The sets only need three hours of daylight to produce seven hours of electricity.

Solar Paint

Photo Credit: Kurzweil/Matthew P. Genovese, Ian V. Lightcap, and Prashant V. Kamat

So what do you do if you’ve replaced all of your windows and curtains with bleeding-edge solar versions, but then you notice you have walls that could be soaking up rays for you? Then what? Have no fear, there are people working on solar paint to fill in those gaps. Using the same basic principal as the coating on the solar windows, using conductive photovoltaic nanoparticles, researches at Notre Dame university have developed a compound that can be sprayed on a surface which then generates electricity when hit by light.

It’s not perfect yet; it has to be sprayed on a conductive surface (steel, for example) and it does not generate much energy yet, but they are already actively searching for a means to amplify the amount of electricity generated. Someday in the not too distant future, we may be able to turn all of our unused surfaces into solar cells.

The primary advantage to the paint is the ease of setup; all you need is a flat conductive surface and the paint. Once they get it to a more usable energy output, this could revolutionize how people power their homes. Imagine a time when we actually look forward to blisteringly hot summer days instead of worrying about roasting during a brownout.

Solar Supercapacitors

Photo Credit: Inhabitat

But what about those brownouts? Sure, the solar paint drapes and windows work great during the day, but what about night time when there is no sun? Do they work as moon collectors?

Well, sadly, no, but they may not need to. Scientists in India recently developed a solar supercapcitor; basically a solar panel that stores its energy for later use. While a quick Google search shows you can find quite a few tutorials on how to wire together a set of photovoltaic cells and a capacitor on your own, the Indian scientists created the world’s first truly integrated system.

With this setup, you would not need a separate storage unit for nights and cloudy days, the solar cells themselves would supply the needed energy during the off hours. The current prototype can use four hours of sunlight to power a laptop for two hours. While that may not sound like much when compared to the solar textiles, keep in mind an LED uses much less power than a Macbook.

They are looking to improve upon their current design, which uses off the shelf parts with thinner photovoltaics and carbon-based storage and structure.

Self-Recharging Cell Phones

Photo Credit: Phys.org

Most cell and smart phones these days use LED screens, which are a step above the old LCD screens in that they use individual light emitting diodes to back-light a traditional LCD screen. While these are was more efficient than a traditional back-lit LCD, there are still a lot of downsides. Enter OLEDs, or Organic LEDs. No, they aren’t grown on a farm in Vermont; the “organic” means that they are carbon based. OLEDs can use the diodes themselves to create the red, green and blue screens use to give their amazing pictures, so there is no need for the liquid crystal screen or a back-light, they handle everything on their own.

But there are some downsides to this great new technology; one is that the blue OLEDs have only a fraction the lifespan of the red and green. The other is that they lose roughly 64% of the light they generate out the sides, which means 64% of the power you are using is lighting the interior of the phone (or eventually TV), which is wasteful by anyone’s standard.

So some brilliant people at the University of Cambridge came up with a solution; line the edges with solar cells and recoup that lost light. They also integrated the whole thing with a thin-film supercapacitor so that the captured light could be immediately stored. Now, it’s not an entirely closed system; you will still be losing 36% of the light out the front, and the current ceiling on the photovoltaics is 11% efficiency, meaning that 89% of that 64% is still lost (it is not converted into electricity), but they are looking for ways to increase that efficiency, including ways of turning kinetic energy into power.

We may some day soon have ultra efficient phones that will allow us to watch day’s worth of TV on our phones without recharging. At least the phones will be efficient.

Solar “Traps”

Photo Credit: Materialica/Yan Yao

Speaking of increasing efficiency… But first, an aside. have you ever been to the Capitol Building in Washington DC? Or maybe the Parthenon? There is a little trick you can play while you’re there; go to one side of the dome and have a friend go to the other, then whisper something. The circular shape allows the sound waves to travel along the perimeter without interruption, and as a result, your friend can hear you just fine. It’s called a “Whispering Gallery.”

But what do domes and sound waves have to do with solar collectors?

Well, first off, while light is a particle, it is also a wave, as Einstein told us. This is good news, because waves do cool things, like travel around domes really well. Researchers at Stanford discovered that by making nanoparticle “shells” out of silica (essentially glass), they could create miniature whispering galleries that work for light the way domes work for sound, recirculating the light and preventing it from scattering around. This means that the surface holds onto the light, which obviously is a good thing if you are trying to use that light to, say, create electricity.

The light deposits energy inside the shell as it circles around inside, and they have found that by layering the shells, they can absorb 75% of the light that hits the surface. That is way better than traditional solar cells that are often highly reflective, and the nanoshells require less time to absorb a useable amount of energy and can use a fraction of the thickness of traditional photovoltaics. The best part is that they use readily available materials to produce; essentially sand. Now if someone could come up with a way to use the sun and sand in a single application…

The Solar Sinter

Photo Credit:Kayser

How is that for a setup? Markus Kayser developed a machine that uses the two most abundant resources in the desert to build objects; the sun and the sand. It is effectively a 3D printer that uses the sun to melt sand into glass and render 3D digital models into real-world glass sculptures. This video shows it at work and trumps every vinegar volcano and potato battery ever constructed in a home lab…

Typical 3D printers use resin and lasers to generate real-world renderings of computer generated models. The solar sinter uses the sun to create the “Laser” as well as solar panels to power the electrical components, like the computer that drives it.

It takes a while to run, but nothing free ever comes easy. Its current design requires some human interaction, but no doubt with some time, they could completely automate it and generate prototypes for free using deserts

or maybe they could just make some really cool art in the greenest way imaginable.