This rendering depicts how an office might appear with the University of Cincinnati's SmartLight off (above) and on (below). Sunlight is directed to different spaces, including to a "SmartTrackLight" in the outer hallway. Credit: Timothy ZarkiA pair of University of Cincinnati researchers has seen the light – a bright, powerful light – and it just might change the future of how building interiors are brightened .
In fact, that light comes directly from the sun. And with the help of tiny, electrofluidic cells and a series of open-air "ducts," sunlight can naturally illuminate windowless work spaces deep inside office buildings and excess energy can be harnessed, stored and directed to other applications.
This new technology is called SmartLight, and it's the result of an interdisciplinary research collaboration between UC's Anton Harfmann and Jason Heikenfeld. Their research paper "Smart Light – Enhancing Fenestration to Improve Solar Distribution in Buildings" was recently presented at Italy's CasaClima international energy forum.
"The SmartLight technology would be groundbreaking. It would be game changing," says Harfmann, an associate professor in UC's School of Architecture and Interior Design. "This would change the equation for energy. It would change the way buildings are designed and renovated. It would change the way we would use energy and deal with the reality of the sun. It has all sorts of benefits and implications that I don't think we've even begun to touch."
Major improvement through minimal adjustments
There's a simple question SmartLight addresses: Is there a smarter way to use sunlight? Every day the sun's rays hit Earth with more than enough energy to meet many of society's energy demands, but existing technologies designed to harness that energy, such as photovoltaic cells, aren't very efficient. A typical photovoltaic array loses most of the sun's energy when it gets converted into electricity. But with SmartLight, Harfmann says the sunlight channeled through the system stays, and is used, in its original form. This method is far more efficient than converting light into electricity then back into light and would be far more sustainable than generating electric light by burning fossil fuels or releasing nuclear energy.
The technology could be applied to any building – big or small, old or new, residential or commercial. But Harfmann and Heikenfeld believe it will have the greatest impact on large commercial buildings. The U.S. Department of Energy's Energy Information Administration shows that 21 percent of commercial sector electricity consumption went toward lighting in 2011. Harfmann calls the energy demand for lighting in big, commercial buildings "the major energy hog," and he says energy needed to occupy buildings accounts for close to 50 percent of the total energy consumed by humans.
SmartLight could help shift that energy imbalance. It works like this: A narrow grid of electrofluidic cells which is self-powered by embedded photovoltaics is applied near the top of a window. Each tiny cell ¬– only a few millimeters wide – contains fluid with optical properties as good or better than glass. The surface tension of the fluid can be rapidly manipulated into shapes such as lenses or prisms through minimal electrical stimulation – about 10,000 to 100,000 times less power than what's needed to light a traditional incandescent bulb. In this way, sunlight passing through the cell can be controlled.
This diagram shows how the University of Cincinnati's SmartLight can direct sunlight from the outside of a building (far right) to the inner part of a building and to a centralized harvesting- and energy-storage hub (far left). Credit: Anton Harfmann, UC
The grid might direct some light to reflect off the ceiling to provide ambient room lighting. Other light might get focused toward special fixtures for task lighting. Yet another portion of light might be transmitted across the empty, uppermost spaces in a room to an existing or newly installed transom window fitted with its own electrofluidic grid. From there, the process could be repeated to enable sunlight to reach the deepest, most "light-locked" areas of any building. And it's all done without needing to install new wiring, ducts, tubes or cables.
"You're using space that's entirely available already. Even if I want to retrofit to existing architecture, I've got the space and the ability to do so," says Heikenfeld, professor of electrical engineering and computer systems and creator of the Smart Light's electrofluidic cells. "And you don't need something mechanical and bulky, like a motor whirring in the corner of your office steering the light. It just looks like a piece of glass that all of a sudden switches."
Smart approach allows dynamic response
As for switching, Harfmann envisions a workplace where physical light switches join other anachronistic office equipment like mouse pads or bulky CRT monitors. Plans call for SmartLight to be controlled wirelessly via a mobile software application. So instead of manually flipping a switch on a wall, a user would indicate their lighting preferences through an app on their mobile device, and SmartLight would regulate the room's brightness accordingly. SmartLight could even use geolocation data from the app to respond when a user enters or leaves a room or when they change seats within the room by manipulating Wi-Fi-enabled light fixtures.
"SmartLight would be controlled wirelessly. There would be no wires to run. You wouldn't have light switches in the room. You wouldn't have electricity routed in the walls," Harfmann says. "You would walk into a room and lights would switch on because your smartphone knows where you are and is communicating with the SmartLight system."
But what happens at night or on cloudy days? That's where SmartLight's energy storage ability comes in. On a typical sunny day, sunlight strikes a facade at a rate that's often hundreds of times greater than what is needed to light the entire building. SmartLight can funnel surplus light into a centralized harvesting- and energy-storing hub within the building. The stored energy could then be used to beam electrical lighting back through the building when natural light levels are low. The SmartLight's grid is so responsive – each cell can switch by the second – it can react dynamically to varying light levels throughout the day, meaning office lighting levels would remain constant during bright mornings spent catching up on email, stormy lunch hours spent eating at your desk, and late nights spent reviewing the budget.
With such potential for energy storage, a building's electrical network also could tap into the centralized hub and use the stockpiled energy to power other needs, such as heating and cooling. And if centralized collection of surplus sunlight isn't possible inside some existing structures, the light could even be sent straight through a building to a neighboring collection facility.
A user could control SmartLight through a mobile app, as depicted in this rendering. Credit: Anton Harfmann
Partnering for a brighter future
Heikenfeld says much of the science and technology required to make the Smart Light commercially viable already exists. He and Harfmann have begun evaluating materials and advanced manufacturing methods. The only thing missing at this point is enough funding to create a large-scale prototype which could call the attention of government or industry partners interested in bringing SmartLight to market.
"We're going to look for some substantial funds to really put a meaningful program together," Heikenfeld says. "We've already done a lot of the seed work. We're at the point where it would be a big, commercially driven type of effort. The next step is the tough part. How do you translate that into commercial products?"
Harfmann and Heikenfeld originally began developing the idea for the Smart Light years ago. Harfmann was one of the leaders on UC's team in the 2007 Solar Decathlon, a global competition to build the planet's best solar house. Harfmann, an associate dean in UC's College of Design, Architecture, Art, and Planning, collaborated with faculty from other disciplines, including the College of Engineering & Applied Science. That led to his relationship with Heikenfeld and eventually the first discussions of the SmartLight concept.
The cross-college efforts of Harfmann and Heikenfeld align with the university's UC2019 Academic Master Plan goal of expanding collaborative engagement to advance the common good. Additionally, the SmartLight project exemplifies the UC2019 vision by transforming the world through research and creating a deliberate and responsible approach to our environment, resources and operations.
The innovation that results from similar collaborations taking place everywhere at UC, Heikenfeld says, is part of what helps make the university a leader in so many fields.
"A step beyond just working with someone in a multidisciplinary fashion, and where a lot of these partnerships go well, is when you take the time to learn enough about someone else's discipline that you can then begin to inject innovation into it, but not independently," Heikenfeld says. "It's more than just bringing multidisciplinary folks together. You have to stretch yourself to the point where you begin to understand the drivers and some of the fundamentals of the other disciplines as well. One of UC's greatest strengths is our diversity, this is in the classic sense of the term, but also in terms of academic thinking and expertise, which is a great melting pot for big, new ideas."
‘soft rocker‘ is a solar powered outdoor rocking lounger whereby you can relax and recharge your electronics. Developed by architecture students at MIT, lead by professor Sheila Kennedy, the furniture piece uses the human power of balance to create an interactive 1.5 axis, 35 watt solar tracking system. The lounger utilizes a 12-ampere hour battery storing the solar energy harvested during sunlight hours so you to charge your gadgets even after sunset.
A number of ‘soft rockers’ are currently installed within MIT’s killian court for use until the end of this weekend.
Up close of the ‘soft rocker’
The loungers make for a good place to socialize and engage in group work
The solar powered charging station
The battery also allows you to turn on a strip of light tape that runs along the interior of the lounger
The U.S. Patent and Trademark Office on
Thursday published an Apple patent application for a unique solar-ready
power management system that can be integrated into the company's
portable product lineup, negating the need for bulky external
converters.
Source: USPTO
Apple already has a number of solar power inventions to its name, but Thursday's filing is one of the first to propose a solution that can be made viable in the near term.
As noted in the patent,
titled "Power management systems for accepting adapter and solar power
in electronic devices," Apple is not looking to invent a completely new
solar power solution, as it has done in the past.
Instead, the proposed method would take advantage of existing
technologies and, more importantly, can be produced with currently
available components.
As electronics become more powerful with each successive generation,
they in turn require more power, which for portables is limited by
battery capacities. Apple notes these devices are therefore dependent on
availability of mains electricity, or a wall outlet.
There are solutions, such as solar panels, that can add extra juice on
the go, but existing tech relies on external circuits to convert solar
panel power to a form compatible with electronic devices. More
specifically, iPhones and MacBooks accept specific direct current (DC)
voltages. While an option, integrated solar panels have proven bulky and
the aesthetics may be less than desirable for Apple.
According to the filing, the integrated power management system would
include a system micro controller (SMC) and a charger. Power would flow
to the system from either an AC-to-DC adapter or directly from a
photovoltaic solar panel's output, which is DC only, then be measured
and converted to the necessary voltage.
In this embodiment, charger's power stage incorporates what is known as a
buck converter, or step-down DC-to-DC converter. Incoming power is
monitored by a charger IC, converted to an appropriate voltage and fed
into either an input current loop, a battery current loop, an output
voltage loop, or an input voltage loop to control charging.
The SMC monitors system power metrics like battery charge, health and
input power type, among others, and manages the power stage accordingly.
In the case of solar power input, the SMC would track a maximum power
point for the panels by any number of methods, including multiplying
current with voltage. Once this point is established, SMC sends a signal
to the charger IC, which uses the data to adjust a reference voltage
for maximum power point tracking (MPPT). This point determines what
voltage changes need to be applied to the solar panel input.
Finally, Apple notes that the power management system can accept both solar and mains power simultaneously.
Illustration of power management system with incorporated MPPT.
All processing and adjustments can be accomplished with established
techniques and deployed in a reasonably small component package, making
the invention suitable for use in iPhones and MacBooks. While solar tech
is somewhat of a rarity, the alternative energy solution is becoming
more popular with mainstream consumers looking for on-the-go power.
Apple's solar power converter patent application was first filed for in
2012 and credits Kisun Lee, Manisha P. Pandya and Shimon Elkayam as its
inventors.
The first supercapacitor composed of silicon was recently created by researchers at Vanderbilt University — the novel supercapacitor opens up a number of very interesting possibilities with regard to solar cell technology and mobile electronics. In particular, the researchers note the possibility of developing solar cells that can provide electricity for a full 24 hours of the day, and of developing mobile phones that can recharge in seconds and work for weeks between charges.
The great strength of the new supercapacitor is that, since its created out of silicon, it can simply be built into a silicon chip along with and at the same time as the same microelectronic circuitry that it powers. The researchers even mention the possibility of constructing these power cells “out of the excess silicon that exists in the current generation of solar cells, sensors, mobile phones and a variety of other electromechanical devices, providing a considerable cost savings.”
Silicon chip with porous surface next to the special furnace where it was coated with graphene to create a supercapacitor electrode. Image Credit: Joe Howell / Vanderbilt
“If you ask experts about making a supercapacitor out of silicon, they will tell you it is a crazy idea,” stated Cary Pint, the assistant professor of mechanical engineering who headed the development. “But we’ve found an easy way to do it.”
Most research to date to improve the energy density of supercapacitors has focused on the utilization of carbon-based nanomaterials like graphene and nanotubes, but because of the great difficulty in “constructing high-performance, functional devices out of nanoscale building blocks with any level of control,” improvements have been slow. So, the researchers decided to try something radically new — utilizing porous silicon, a material with a controllable and well-defined nanostructure made by electrochemically etching the surface of a silicon wafer.
“This allowed the researchers to create surfaces
with optimal nanostructures for supercapacitor electrodes, but it left them
with a major problem. Silicon is generally considered unsuitable for use in
supercapacitors because it reacts readily with some of the chemicals in the
electrolytes that provide the ions that store the electrical charge.
With experience in growing carbon nanostructures,
Pint’s group decided to try to coat the porous silicon surface with carbon.
When the researchers pulled the porous silicon out of the furnace, they found
that it had turned from orange to purple or black. When they inspected it under
a powerful scanning electron microscope they found that it looked nearly
identical to the original material but it was coated by a layer of graphene a
few nanometers thick.”
“We had no idea what would happen,” Pint explained. “Typically, researchers grow graphene from silicon-carbide materials at temperatures in excess of 1400 degrees Celsius. But at lower temperatures — 600 to 700 degrees Celsius — we certainly didn’t expect graphene-like material growth.”
After testing the coated material, the researchers found that it had chemically stabilized the silicon surface — and that, when it was used to create supercapacitors, the graphene coating “improved energy densities by over two orders of magnitude compared to those made from uncoated porous silicon and significantly better than commercial supercapacitors.”
The researchers think that this approach very likely isn’t specific to graphene. “The ability to engineer surfaces with atomically thin layers of materials combined with the control achieved in designing porous materials opens opportunities for a number of different applications beyond energy storage,” Pint argued.
“Despite the excellent device performance we achieved, our goal wasn’t to create devices with record performance,” Pint continued. “It was to develop a road map for integrated energy storage. Silicon is an ideal material to focus on because it is the basis of so much of our modern technology and applications. In addition, most of the silicon in existing devices remains unused since it is very expensive and wasteful to produce thin silicon wafers.”
The researchers are now pursuing this line of thought — looking to develop energy storage that can be built into the excess materials and/or unused back-sides of solar cells.
The new research was detailed in a paper published in the journal Scientific Reports.
A Renault Spark SRT-01E FIA Formula E race car is presented at the booth of Michelin during the media day of the IAA (Internationale Automobil Ausstellung) international motor show in Frankfurt am Main, western Germany, on September 10, 2013 Formula One dominator Sebastian Vettel gave short shrift Saturday to the new, electric Formula E series, saying it would be far too quiet and was "not the future".
Five teams have already been signed for the planned field of 10 to raceelectric cars in city centres around the world, starting in Beijing next September.
"I don't like it at all, I think it's not the future," Vettel said at the Indian Grand Prix, where victory on Sunday will give him a fourth consecutive drivers title.
"I think people come here to feel Formula One and there is not much to feel when a car goes by and you don't even hear anything but the wind.
"Maybe I am very old-fashioned, but I think Formula One needs to scream, needs to be loud and there needs to be vibration."
Vettel said he will never forget the first time he went to Formula One in 1992 to watch a free practice at Hockenheim.
"Even though it was wet and the cars did not go out, once they did their installation laps it was a great feeling just to be there and hear them coming through the forest," he said.
However, Mercedes' Nico Rosberg, who will start Sunday's race on the front row alongside pole-sitter Vettel, was more positive about the eco-friendly initiative.
"It's an interesting thing for sure, something new and I know there is a lot of interest," Rosberg said. "It's planned to be in cities (rather than normal circuits), so it's bringing the race to the people, not the people to the race.
"It's a bit of the future, so it will be interesting to see how it goes. We need to wait and see."
Taiwan-based Greendix solar panel designer and manufacturer recently released images of the world’s first solar powered soccer ball . The traditional black pentagonal-shaped leather patches, which make a soccer ball instantly recognizable, have been replaced with solar cells of the same size and shape.
“The main goal of this project was to prove that solar panels can be integrated into any object that we interact with on a daily basis and to push the limits of what is possible with solar panels,” explained Joseph Lin fromGreendix.
The ball's solar panels power the built-in motion sensors and audio device, which could possibly enable visually impaired people to play soccer/football. The ball prototypes emit a tracking sound each time they get kicked.
“We hope this solar football will strike the imagination of designers everywhere as solar power can now be seamlessly integrated into any imaginable device. In the future, footballs could be integrated with other sensors or LEDs and get their power from the sun,” added Michael Yu at Sonelis Technologies. California-based Sonelis Technologies is handling the distribution for the Greendix produce line.
Chalk up another score for aluminum. The humble — as in, cheap and abundant — metal has been popping up all over the sustainable tech field, and in the latest development, an international research team has demonstrated that nanoscale LEGO-style array of aluminum studs can improve solar cell efficiency by up to 22 percent. If the labwork translates into commercial development, that will help drive the rapidly sinking cost of solar power down even farther.
That’s a significant breakthrough, because until now gold and silver have been the focus of attention in the solar cell efficiency field due to their vigorous interaction with light.
However, the research team, spearheaded by Imperial College in London, compared the results of theirLEGO-style aluminum array with identical arrays made of gold and silver. They found that the more expensive metals did not boost solar cell efficiency as much as aluminum, and in fact resulted in reduced efficiency.
How A LEGO-Like Array Builds Solar Cell Efficiency
The new research was recently published in the journal Nature under the mouthful “Loss mitigation in plasmonic solar cells: aluminium nanoparticles for broadband photocurrent enhancements in GaAs photodiodes.”
The idea behind the nanoscale LEGO studs is to force light to bend, enabling layers of energy-absorbing material to trap more solar energy.
That reduces the amount of absorbing material needed, which in turn helps to lower the cost of production.
The team tested their LEGO studs on thin film gallium arsenide solar cells. Writer Simon Levey of Imperial College describes it like this:
Dr Hylton and his colleagues attached rows of aluminium cylinders just 100 nanometres across to the top of the solar panel, where they interact with passing light, causing individual light rays to change course. More energy is extracted from the light as the rays become effectively trapped inside the solar panel and travel for longer distances through its absorbing layer.
As for the key factor that enables aluminum to vault over gold and silver, the precious metals tend to absorb light into themselves.
Aluminum, in contrast, simply bends and scatters light, passing it along to the solar cell. As an added advantage, its light weight and flexibility make it compatible with the new generation of flexible solar cells.
Aluminum And Sustainable Technology
Precious metals and rare earths get a lot of the headlines in solar cell tech, but aluminum has been steadily gaining under the radar.
This is the first example we’ve covered that involves integrating aluminum into a solar cell, but there are a growing number of examples of aluminum used in solar modules.
Aluminum is also making headway in the transportation field. Aside from contributing to lighter and thereby more fuel efficient vehicles, researchers are checking out its potential use in metal-air batteries.
