This Window Can Help Power A Skyscraper

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This window can help power a skyscraper: Imagine if windows could be designed to collect the electricity used to power a home or a skyscraper. The technology that could make that a reality might be closer than you think. In fact, it could be ready by next year, said John Conklin, the president and CEO of SolarWindow Technologies Inc.

This is something that would revolutionize clean energy for large commercial buildings, which are the company's primary target market, Conklin told National Observer. “I truly believe it’s one of the most disruptive and perhaps one of the single greatest breakthroughs in clean energy ever,” he said.

Maintaining the window's transparency a challenge:

Designing the technology has meant working out solutions. The biggest has been ensuring the windows remain transparent while still generating enough electricity. The windows require a special coating that turns ordinary glass into a conductor that transforms energy into electricity that feeds directly into the building's power system.

During Maryland-based SolarWindow’s early years in 2009 and 2010, a number of individuals told the firm’s team that it would be impossible for them to create a transparent photo-voltaic technology. “We defied that,” Conklin said.

The U.S. Department of Energy's National Renewable Energy Lab (NREL) has been working with SolarWindow on the technology and the two partners are now focused on ensuring that the coatings can work on larger areas of glass. “Challenges are always there. Nothing is easy in this area,” said Maikel van Hest, a senior scientist in the Thin Film and Processing Group within the National Center for Photovoltaics at NREL.

Right now, SolarWindow estimates that its technology can generate 50 times more energy than rooftop solar panels would in a 50-storey building. Using all four sides of the building, in a 50-story glass skyscraper, this would consist of six acres of glass - enough to provide far more than the one megawatt of power that would come from a rooftop solar array, Conklin said. This is much more space than what's available on a skyscraper’s roof. “The name of the game is real estate,” he said.

Overall, the refurbished windows could offset the equivalent of the emissions from vehicles traveling nearly 3.5 million kilometres by reducing energy demands in a 50-storey building, Conklin estimated. But he also noted that skyscrapers use huge amounts of energy and that the new solar windows would only cover somewhere between 30 to 50 per cent of total power consumption. “This is a tremendous opportunity for the environment, a tremendous opportunity for renewable energy and especially for tall towers and skyscrapers to finally get some renewable energy.”

Home owners might one day find the same technology in their houses. The more glass a home has, the more power it would be able to generate. But for now, SolarWindow plans to pursue the more lucrative commercial market first, where Conklin believes there are significant business opportunities. He said the commercial market is huge, estimated to be a $100-billion global market for flat glass and fabricated windows. Out of that, SolarWindow is targeting some five million commercial buildings in the U.S.

Here's how the SolarWindow works:

SolarWindow’s organic photovoltaic technology uses ordinary window glass and then applies different layers of coatings made of carbon, nitrogen, hydrogen and oxygen are applied. Transparent conductors form two layers. Between the two is a third layer, which absorbs light. When it comes in contact with the chemical coating, the solar energy is transformed into electrons. The movement of the electrons produces the electricity on the surface of the glass. The conductors on each side transport the electricity to ultra-thin wires inside the window frame. Those in turn feed the energy into the building’s electrical systems.

Conklin, an industrial consultant who has studied chemical engineering, helped develop similar surfacing coating techniques used in the fabrication of the United States Stealth Battleship prototype while at Excel Precision Inc. He is also the founder and vice president of National Solar Systems, LLC, a New York-based renewable and alternative energy design and installation firm.

SolarWindow is not alone in trying to develop solar-powered windows. Some companies, for example, have small strips over the glass that absorb the light. But these strips wind up creating a pattern that’s almost like having window blinds, according to van Hest.

But while no company has yet managed to commercialize a truly see-through window, SolarWindow says their windows will be like any other windows and will come in architecturally desirable tints and shades. “That’s the nice thing about SolarWindow’s photovoltaic, the way they’re doing it. It’s not obstructing your view from the outside world,” said van Hest from NREL, the U.S. government lab.

But he added that with every step comes a new hurdle, such as choice of materials or how those materials are applied. “Yeah there’s definitely some hurdles, but we have pathways on taking those hurdles and taking it to the next step, which would be commercialization.”

Paula McGarrigle, managing director of SOLAS Energy Consulting Inc. in Calgary, said SolarWindow’s concept is great. “I love the idea of using the horizontal spaces on windows to generate electricity.” According to McGarrigle, the economics of the technology will depend on a number of variables such as the energy load of the building, how much surface area is available on a building and the power prices of a jurisdiction.

Conklin said the cost of SolarWindow’s technology would be “low,” and calls it a “very small add-on price point to an existing window,” which would be paid back in less than one year for a skyscraper.

Solar power from all four sides of a building:

In order to get their technology to market, SolarWindow needs to raise additional capital. To date, the company has relied on private placements from investors. The firm also wants to form partnerships with glass and window fabrication companies as well as chemical companies.

Conklin, who describes himself as risk-averse, said it’s not his intention to start the company up in a $45-$50-million production facility when glass manufacturers already exist. “We’ve already demonstrated our process can be seamlessly integrated into a glass manufacturer or window fabricator and coated right at their facility.”

Partnerships with the right chemical firms are important because the technology employs various chemicals applied to glass to generate the electricity. Such partnerships will enable SolarWindow to hold down its operating expenses and capital costs while achieving an affordable price for the windows.

The technology is able to generate power on all four sides of a building, not just on the south-facing side in the Northern hemisphere. Conklin said the coatings can create electricity under shaded, diffused and low-light conditions.

That ability to use the same glass on all four sides of a building will make the technology attractive to architects, developers and designers who are looking to generate renewable energy but still maintain the aesthetic beauty of a building, Conklin added.

The End Of Window Cleaning

A scanning electron miscroscope photograph shows the pyramid-like nanostructures engraved onto glass: at 200nm they are 100 times smaller than a human hair. Controlling the surface morphology at the nanoscale allows scientists to tailor how the glass interacts with liquids and light with high precision.

Nature inspired nano-structures mean no more cleaning windows: A revolutionary new type of smart window could cut window-cleaning costs in tall buildings while reducing heating bills and boosting worker productivity. Developed by UCL (University College London) with support from the Engineering and Physical Sciences Research Council (EPSRC), prototype samples confirm that the glass can deliver three key benefits:

Self-cleaning: The window is ultra-resistant to water, so rain hitting the outside forms spherical droplets that roll easily over the surface – picking up dirt, dust and other contaminants and carrying them away. This is due to the pencil-like, conical design of nanostructures engraved onto the glass, trapping air and ensuring only a tiny amount of water comes into contact with the surface. This is different from normal glass, where raindrops cling to the surface, slide down more slowly and leave marks behind.

Energy-saving: The glass is coated with a very thin (5-10 nanometre) film of vanadium dioxide which during cold periods stops thermal radiation escaping and so prevents heat loss; during hot periods it prevents infrared radiation from the sun entering the building. Vanadium dioxide is a cheap and abundant material, combining with the thinness of the coating to offer real cost and sustainability advantages over silver/gold-based and other coatings used by current energy-saving windows.

Anti-glare: The design of the nanostructures also gives the windows the same anti-reflective properties found in the eyes of moths and other creatures that have evolved to hide from predators. It cuts the amount of light reflected internally in a room to less than 5 per cent – compared with the 20-30 per cent achieved by other prototype vanadium dioxide coated, energy-saving windows – with this reduction in 'glare' providing a big boost to occupant comfort.

"This is the first time that a nanostructure has been combined with a thermochromic coating. The bio-inspired nanostructure amplifies the thermochromics properties of the coating and the net result is a self-cleaning, highly performing smart window," said Dr Ioannis Papakonstantinou of UCL.

A smart glass prototype developed by the UCL team. The dark areas are decorated with the nanostructures, which significantly suppress reflections. They also repel water forcing it to form nearly spherical droplets and preventing it from wetting the surface of the glass. The UCL logo is made of untreated glass and appears significantly more reflective compared with its surrounding region.

The UCL team calculate that the windows could result in a reduction in heating bills of up to 40 per cent, with the precise amount in any particular case depending on the exact latitude of the building where they are incorporated. Windows made of the ground-breaking glass could be especially well-suited to use in high-rise office buildings.

Dr Ioannis Papakonstantinou of UCL, project leader, explains: "It's currently estimated that, because of the obvious difficulties involved, the cost of cleaning a skyscraper's windows in its first 5 years is the same as the original cost of installing them. Our glass could drastically cut this expenditure, quite apart from the appeal of lower energy bills and improved occupant productivity thanks to less glare. As the trend in architecture continues towards the inclusion of more glass, it's vital that windows are as low-maintenance as possible."

In only five years, the cost of cleaning skyscraper windows reaches the amount it cost to install them.

Discussions are now under way with UK glass manufacturers with a view to driving this new window concept towards commercialisation. The key is to develop ways of scaling up the nano manufacturing methods that the UCL team have specially developed to produce the glass, as well as scaling up the vanadium dioxide coating process. Smart windows could begin to reach the market within around 3-5 years, depending on the team's success in securing industrial interest.

Dr Papakonstantinou says: "We also hope to develop a 'smart' film that incorporates our nanostructures and can easily be added to conventional domestic, office, factory and other windows on a DIY basis to deliver the triple benefit of lower energy use, less light reflection and self-cleaning, without significantly affecting aesthetics." Professor Philip Nelson, Chief Executive of EPSRC said: "This project is an example of how investing in excellent research drives innovation to produce tangible benefits. In this case the new technique could deliver both energy savings and cost reductions."

Invisible Solar Panels Will Replace Glass

“Invisible” Solar Panels are on the Way - Window gazers of the future may soon find themselves looking right through an energy-producing transparent glass solar panel, if the folks at the National Renewable Energy Laboratory are on the right track. Working with the company New Energy Technologies, Inc., the lab has produced a transparent photovoltaic module that is 14 times bigger than its last attempt.

Windows that double as solar panels:

At 170 square centimeters (about 26 square inches), the new module is about the size of a small window. If the technology can be ramped up to a more useful scale, practically any glass window could double as a clean energy generator, with the embedded photovoltaic cell all but invisible. The largest device of its kind produced at NREL, the new module represents a breakthrough in organic photovoltaic cell (OPV) technology according to a statement by Dr. David S. Ginley of NREL, who said that integrating solar technology into window glass represents a “promising avenue for OPV deployment.”

Organic photovoltaic technology set to rise:

In contrast to conventional solar technology based on silicon, OPV cells can be made from a variety of inexpensive polymers (plastics), which can be produced in liquid form and sprayed onto a substrate, or applied using a high volume, inexpensive roll-to-roll manufacturing process. The two sticking main sticking points so far have been increasing the size of the solar module, and increasing its efficiency. The solar energy conversion efficiency of other solar technologies has been trending up in the double digits but OPV efficiency is currently stuck around eight percent according to NREL.

Though OPV is starting from a lowly place on the conversion efficiency totem pole, its potential for building-integrated usage puts it in a strong position in the solar industry. The relatively low conversion rate could be counterbalanced by the potential for extremely low installation costs compared to other solar technologies. See-through glass solar panels could simply be substituted for conventional window glass at a marginal increase in cost, rather than being treated as an expensive add-on.

A place in the sun(shot) for OPV:

Lowering the overall installed cost of solar power is a primary goal of President Obama’s SunShot Initiative, which aims to make solar energy compete on price against fossil fuels within the next few years. That partly explains why NREL is so gung-ho on OPV technology despite its low efficiency. It should be noted, though, that the focus on OPV predates the Obama Administration. OPV was part of the Solar America initiative under the Bush Administration. Despite a conversion efficiency of only five percent at the time, a 2007 Department of Energy draft report identified some key benefits of developing OPV technology, including “the inherent low materials cost and low-energy, high-throughput processing technologies, and because of the huge variety of possible organic systems.”

OPV and American-made energy:

Another aspect of NREL’s interest in OPV has to do with reliability and stability of price and supply, which are key elements in President Obama’s broader “American-made energy” pitch. The use of a variety of polymers would enable the U.S. solar industry to overcome a major obstacle that derives from reliance on silicon-based solar technology, and that is the price fluctuation of a single key material – silicon – on the open market.

According to a report last week in Bloomberg News, China, which it describes as the “biggest supplier to solar-panel manufacturers worldwide,” has shut down almost a third of its polysilicon production after prices fell by 60 percent, a move that is expected to result in a quick return to higher prices. However, it’s too soon to say good-bye to silicon forever. NREL is also working with another small company, Innovalight, to develop solar modules based on a low cost, nano-engineered spray-on liquid silicon process.

Also check out:

New Thin Film Material Promises Power Generating Windows.

New Transparent Thin Film Solar Material Could Turn Windows into Solar Power Generators.

Government Scientists Put See-Through Solar Windows on the Fast Track.

Top 10 Solar Technologies to Watch Out For.

Solar Power Graphs to Make You Smile.

Smarter Homes, Windows & Window Cleaning Apparel

'Smart' electrochromic and gasochromic windows latest in green innovations: For the past few years, a seminar on new and innovative green building products has been a staple at Construct Canada. This year was no exception as BuildGreen Solutions partner Rodney Wilts updated architects, engineers and contractors on the some of the “great” green products that have crossed his desk in the past 12 months. “This (presentation) is a bit of a hodge-podge of things that we look at in the green building world,” said Wilts, whose firm works with architects, developers and other organizations to implement sustainable practices in the built environment. 

BuildGreen has managed more than 40 LEED projects in Canada, the U.S. and Mexico. Wilts, whose firm is part of the Windmill Developments family of companies, said windows “are getting serious” as manufacturers compete to build the most energy-efficient products. Soon to hit the market, he said, are “smart” electrochromic and gasochromic windows. “We’re seeing leaps and bounds in quality window manufacturing,” Wilts said.

Other green products include a device that monitors energy consumption over a period of time and automatically kills “vampire” power and building-integrated photovoltaic systems. On the materials side, “torrified” wood appears to be catching on “like wildfire,” Wilts said. A chemical-free process is used to heat up the wood, making it less susceptible to mould, rot and fungi. Other green materials include an environemtally friendly drywall product. Wilts, whose firm is based in Ottawa, said clients also are demonstrating increased interest in indoor air quality. One such item that is on the market is a proprietary drywall product that cleans the air, reacts with volatile organic compounds and makes them inert and is highly mould-resistant. “It is no longer enough to be less bad,” Wilts said.

Living walls also are catching on in a big way, he said, noting that a five-storey, plant-covered Biowall has been incorporated into the Algonquin Centre for Construction Excellence in Ottawa. This system helps control humidity while also cleaning the air. Water efficiency is also gaining increased attention, Wilts said. He cited introduction of a greywater reuse system that is suitable for either commercial or residential projects, a dual-flush toilet that has an integrated sink for immediate greywater reuse and a 0.8 gallon per flush, high-efficiency toilet. In his presentation, Wilts also touched on various developments on the green building front, including LEED Canada and the Living Building Challenge, which he described as “LEED on steroids.”

Clothing to harness renewable energy: Silvr Lining, a California based fashion company, has created the Go Collection of clothing with integrated solar power supplies suitable for charging personal communication devices (PCDs), such as cell phones and smart phones, and personal digital assistants (PDAs), such as MP3(4) players. This "wearable" power virtually eliminates the need to recharge at wall sockets. The power supply hardware is easily installed in GO garments in less than one minute, and un‐installed for cleaning just as quickly. The GO Integrated Solar Power System is comprised of 6‐inch by 8‐inch solar panels designed to fit pockets in the front of the garments. As these pockets contain windows to allow the sun's rays to impinge on the active side of each panel, the pockets are referred to as "frames". There are two frames in the GO Utility Vest, four in the GO Director's Jacket, two in the GO Myer's Topper, and two in the GO Cargo Pant that can accommodate panels.

 

The GO Solar Power System contains a power regulator and energy reservoir connected in between the solar panel and the device under charge (DUC). Its function is to efficiently capture the electrical power generated by the solar panel, to store that energy in the reservoir, and to provide the DUC with a highly stable voltage and current at its output compliant with the requirements of the mobile device. The system features "Power Tracking" to condition the energy making the most efficient use of the sun. The output voltage and current are automatically controlled by the regulator to the precise levels required by the DUC.

Simple indicator lights show the status of the system. GO power supplies can also be used separately as carry‐anywhere charging systems for hiking and picnicking, and can be left on the dashboard of the car or placed in the window of the office for complete internal recharging. Silvr Lining also offers the "Booster Panel", a stand‐alone panel about twice as large as the Small Panel. When connected, the Booster Panel would cut in half the charging time of either the reservoir of the Small Panel or a DUC connected to the Small Panel.

The solar panels are constructed of rugged, flexible, and non‐flammable materials able to withstand the sun's radiation, hot and cold temperatures, and wet and dry conditions. Cable assemblies, including cables, connectors, and receptacles, and electronics enclosure are also waterproof. Additional adaptors are also available. More.