The video above is one of several on YouTube.com showing how discarded two-liter plastic soda bottles are being turned into skylights that instantly raise the quality of life for people in severe poverty.
The videos reveal areas of the Philippine Islands and Brazil where people live in small buildings so close together that the inside is almost totally dark both day and night. Electricity is rarely present and if so must be used sparingly. Almost nothing can be done inside the dark houses. Skylights made of discarded plastic soda bottles change that in an instant. In these regions, recycling anything is rare; reusing things is far more common.
Though its origin is not certain, the idea is as clever as it is simple. Start with a discarded two-liter PET (polyethylene terephthalate) soda bottle, fill it with water, and add two capfuls of bleach to prevent bacteria and algae. Fasten a collar to the bottle and insert it in a hole cut in a metal roof, with the bottom three quarters of the bottle inside. The collar fastens to the roof and keeps the bottle from falling through.
Then comes the magic: sunlight strikes the top of the bottle, is refracted by the water, and illuminates the room below. Each skylight-bottle provides light equivalent to a 50- or 60-Watt incandescent bulb.
Besides lighting home interiors, multiple bottle-lights also are being used to light schools and other buildings in these areas. It is a practical solution to a widespread need, and it is obviously economical. Solar tubes selling for around $400 apiece (plus installation) admittedly are higher tech, but the joy that the almost free bottle light brings to the faces in the videos, that’s priceless.
Electroactive polymers that expand or contract when voltage is applied have been under development for a couple of decades, often referred to as artificial muscles because they were initially expected to move the arms of robots. They may yet do that but the first electroactive polymer (EAP) application on the market is moving computer game players – physically and even emotionally.
Applying voltage to elastomeric EAP film flattens it, and expands it horizontally.
What EAPs provide to players using touch-screen game systems is haptic (sense of touch) feedback directly linked to the game features. If something explodes or shakes, the player feels it, and really excited gamers at this year’s Consumer Electronics Show (CES). Other feedback systems use preset vibrations old hat to gamers. The EAP-based feedback was so much more realistic that it wowed them They said it took their gaming to a whole new level.
The gamers were playing on an Apple iPod Touch, but the thrills were supplied from the Mophie Pulse case holding the iPod, which not only sends haptic feedback to the player’s hands, but adds stereo speakers to compound the effects.
The magic that lets the Mophie Pulse thrill the gamers is an EAP-based technology system called ViviTouch from Artificial Muscle Inc. (AMI; Sunnyvale, CA), a subsidiary of Bayer MaterialScience, which developed and supplies the EAP material. In the early 1990s, several government agencies approached SRI International (Menlo Park, CA), then known as Stanford Research Institute, looking for a more efficient actuation technology than the electro-magnetic type then commonly used in robotics.
The ViviTouch actuator containing the EAP material is a fraction of a millimeter thick.
The resulting technology, now commercialized exclusively by Artificial Muscle Inc., consists of a thin layer – tens of microns thin – of dielectric EAP film sandwiched between electrodes. Voltage is applied across the electrodes, causing them to attract each other, which contracts the film’s thickness and expands its area. Response time is fast and, compared with other technologies, the EAP achieves significant motion with less power.
AMI uses cast films of silicone or polyurethane that are tens of microns thin, which is very thin indeed.
Artificial Muscle says the entire ViviTouch package is only a fraction of a millimeter thick, which makes it easy for designers to customize the EAP technology for their applications. The company is currently collaborating with partners in sectors including medical products, vehicle control panels and GPS touchscreens, Braille, and consumer electronics such as mobile computing handsets/smartphones and tablets. AMI expects more mobile computing and video game products to launch in the next year.
The Economist magazine’s Technology Quarterly of September 3, 2011 duly noted the many opportunities for electroactive polymer as a replacement for motors, particularly in small applications like mobile devices or autofocus lenses. It also noted how, like any motor, artificial muscle could be used in reverse, transforming movement into electricity.
Dirk Schapeler, CEO of Artificial Muscle, tells us that reversing the process to create energy from kinetic motion is another AMI development, and that the company is currently developing EAP generators to harness both wind and wave energy.
A team at Case Western University in Cleveland says it has built a polyurethane (PUR) wind turbine blade reinforced with carbon nanotubes, lighter and stronger than currently used materials, which enables the capture of more wind energy.
A variety of materials have been used to make the large – 50- to 100-meter diameter – blade, including carbon fiber, glass fiber, epoxy, aluminum, and even wood. The research team noted that carbon nanotubes are lighter than carbon fibers by volume yet have five times the fiber’s tensile strength. Fatigue testing showed the reinforced PUR lasted eight times longer than epoxy-reinforced fiberglass, and was eight times tougher in delamination fracture tests.
The objective, according to Loos, is not to build longer blades but to build lighter ones that hold their design shape, letting them capture and send more of the wind’s energy to the turbines. The big blades are only one of many components of renewable energy generation that are being enabled and often improved by plastics innovation.
The video above, which shows the assembly of a wind turbine on the Case Western campus, is not connected directly with the new blade announcement. However, in a bit more than two minutes it shows the complete assembly of a wind turbine, bare ground to spinning blades.
“…plastics have a high calorific value, equivalent to or higher than that of coal, so they can provide a very useful source of energy after serving their useful life as a plastics product. Plastics left in municipal waste incinerators (energy-from-waste plants) help generate useful power and heat, while using separated fractions such as paper/plastic mixtures as alternative fuels in power stations offer the prospect of replacing coal and reducing the emission of greenhouse gases.”
We know plastics can be used to produce energy, but what about the idea of turning plastics into fuel? A recent article in the Plain Dealer (Cleveland, OH) focuses on two small Northeast Ohio companies – PolyFlow LLC and Vadxx Energy – that are working to make oil and motor fuel from used polymer and rubber-based consumer products. Both companies are active members of a “cluster” of companies put together by NorTech, a Cleveland nonprofit focused on developing the region’s high-tech economy.
As an example, Polyflow cracks the mixed plastic and rubber waste into aromatics, the building blocks of polymer and rubber manufacturing, using a patented pyrolysis process. Aromatics are traditionally derived through the importation and refining of crude oil. Some of the benefits of this technology include the diversion of plastic and rubber waste from landfills, the creation of green collar jobs and a reduction of our country’s dependence on foreign oil.
Vadxx Energy has a process called “thermal depolymerization” that the company says can break down any plastic, using a proprietary technology that heats the shredded material in an air-tight crucible. The system turns out an oil that, according to the company, is similar to the very best U.S. oil.
Automobiles being powered by old plastic bottles or tires? This idea could be a reality based on the work of companies like PolyFlow and Vadxx Energy. The idea of recovering fuel from plastic is one that should continue to be explored. As the nation seeks to increase its energy security and looks to sources of new and alternative energy, energy recovery through plastics should be part of the mix.
Two new BMWs—a fully electric city car and a four-seat, hybrid sports car—unveiled in Frankfurt, Germany on July 29, 2011 are more than radically cool vehicles. They also mark another step forward for reinforced plastic composites in the automotive sector.
Body panels of BMW’s new i8 hybrid sports car (left) and i3 fully electric city car are carbon-fiber-reinforced plastic, a first for the German carmaker.
The BMW i3 city car and the BMW i8 hybrid sports sedan each have a lightweight aluminum chassis and a “reinforced carbon-fiber body” that the company says compensates for the weight of the batteries. I put those words in quotes because the press material distributed for the launch uses carbon, carbon fiber, and CFRP to describe the bodywork, seemingly saying the structure is carbon. Is it that they don’t want to say what the carbon fibers are reinforcing, or what is holding them together in those body panels?
The “P” in CFRP stands for plastic, which I finally found deep in the ample press material, where CFRP is explained as carbon-fiber-reinforced plastic. The P-word might be used again, I don’t know, but there’s no way to hide the actual CFRP—all the body panels are made of it, and they look good—really good. And if BMW’s engineers are betting on them to perform, the odds are extremely good that they will.
Other carmakers agree.
Porsche and performance electric carmaker Tesla are working with composites, and Land Rover’s new Evoque uses plastic composites for lightweighting. Jaguar is said to be developing a car expected to be one of the fastest in the world, and the C-X75 will also be fuel-efficient thanks to carbon-composite construction and a hybrid power plant, among other things.
BMW uses natural materials in the new i8, but the interior shows the designers also are using plastics—strikingly.
The BMW i8’s transparent, wing-type doors could be quite heavy in glass, but shaped as they are, they well might be plastic. BMW wasn’t saying at the intro.
Speaking of power plants, hats off to a dedicated engineer who may have reached his goal of making a practical composite engine block. Florida-based Matti Holtzberg has made a dozen versions of a composite engine block using a six-piece mold with a removable core for the oil passages. He followed the design of Ford’s 2-liter Duratec engine block but his composite version is 20 pounds lighter, in an industry happy to shed an ounce or a few grams. Car and Driver has more details, including a chronology of Holtzberg’s development of composite engine components that starts in 1969 in Hackensack, NJ. And let’s hear it for engineers who don’t give up on plastics.