Archive for the ‘Physics and Engineering’ Category

Eco-Effective Concepts: Energy Generating T-shirts

A research team with the CSIRO (Commonwealth Scientific and Industrial Research Organization) in Australia is working on a project to integrate energy-generating materials into our clothing. By simply collecting the energy in our movement, vibrations, and friction, our clothing could create enough juice to power up our mobile phone, mp3 player, etc. The Australian Defense Department awarded the team of researchers a $4.4 million grant to deem the technology feasible.

Dr Adam Best, project leader and employee of the CSIRO Energy Technology Division “predicts that the first power shirts - or flexible energy devices- could be developed within five years,” states a Sydney Morning Herald report. Their concept includes the technology of piezoelectrics as the energy generating material. This popularly researched material produces a charge displacement when it is flexed. It naturally occurs in soft chrystalline structures like quartz, and Rochelle salts.

The idea is to develop a fabric woven with piezoelectric material so that any movement on, in, or around your body would stimulate the fiber to generate power. The clothing would be woven with flexible batteries that could act as storage unit series for your devices. The next step is to figure out how to wirelessly transmit that power collected in your t-shirt to your mobile phone without damaging your body due to intense exposure to electro-magnetic fields.

Dr. Best believes that the development of this concept could revolutionize the form and usage of daily appliances. “With printable flexible circuit boards, the day may not be far off when people could make phone calls simply by talking into their collars.”

Interestingly, defense programs and departments are commonly funding projects that develop the potential for remote electrical energy generation. The Australian Defense Department sees this as an opportunity to power “back-to-base” medical monitoring equipment, radios, and other such powered devices used in the field. As it could revolutionize battle in the field, it could also serve as a highly effective tool in field research and remote backpacking trips to power gps devices, emergency radios, data recording and transmittance devices…

There are many similar ideas out there along the lines of energy generating wearables. A collaboration team with members from Michigan Technological University, Arizona State, and NanoSonic, Inc., is developing a backpack with piezoelectric fibers integrated into the straps. Alberto Villarreal, a young San Francisco-based designer, has gained recognition for a concept shoe that harnesses electricity from your step. With the development of these concepts into real products we could be actively moving towards an energy revolution.

Eco-Effective Events: 3rd Solar Decathlon Exhibition Opens Friday

This Friday is the opening day of the 3rd Solar Decathlon Exhibition. The exhibition takes place on the National Mall in Washington DC from October 12th to 20th. Sponsored by the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy, the competition invites 20 teams from colleges and universities across the United States, Germany, Spain, and Canada to participate. The objective is to “design, build, and operate the most attractive, effective, and energy-efficient solar-powered house.” Students have been working on these projects for up to two years; they build them, then deconstruct their projects to transport them across the country and even across oceans only to put them back together again. Teams arrived in Washington last Wednesday, October 3, and have been assembling their homes to prep for Fridays opening.

Powered entirely by the sun, these high-tech homes that exhibit superior efficiency are “likely to help shape America’s clean energy future,” states a press release from the Department of Energy. The first Solar Decathlon was in 2002. I am partially inspired by this event as my old alma mater, the University of Michigan, competed in the 2005 competition. Although Michigan is not competing this year, many of the students from participating schools and prospective schools took notes on the flaws present in 2005, and went home to improve, reinvent, and discover new technologies for this year’s event.

As a result of seeing the 2005 University of Michigan MISO (Michigan Solar) home, I can tell you that these teams are consciously composed. With students from disciplines ranging from Engineering, Architecture, and Design to Urban Planning andEnvironmental Studies, these projects are guaranteed to be well-conceived. “These solar homes are powerful, comfortable, and stylish. They are relaxed, elegant, wasting neither space nor energy.” Since these projects come from an academic setting, a place where exploring concepts and visions for the future is fostered and encouraged, these homes are creative, innovative, and surprising.

Not only is this an opportunity for students to learn, explore, and experience solar home construction; it is also an occasion for the public to come view the solutions and learn about the best in energy efficiency and home design. If you are in the DC area and have a chance to stop by, the exhibition hosts an entrée of tours, seminars, workshops, and talks by students and professionals. Starting this Friday October 12, the exhibition is open to the public. Next Thursday, October 18 is a day devoted to building industry professionals, and the official awards ceremony is next Friday October 19. Enjoy!

Eco-Effective Concepts: “Die Electric” Design

Designer Scott Amron has created a catalogue of conceptual products designed to persuade people to use less energy, or at least think about how many things are plugged into sockets in their homes. The experiment is called "Die Electric," named after the insulating properties of a dielectric material. A dielectric is a substance that is highly resistant to the flow of an electric current. The experiment is about powering down, and rethinking the function of electrical components for purposes other than jacking up the monthly electric bill.

The first set of experiments transforms messy power cords into functional household items: "Shelf" (image above) and "ToothHold." Depending on where the outlets are in your home (usually at a functional reaching level), you now can use this cord to have reachable necessities throughout the home. Whether you are reaching for a toothbrush or a book, your outlets are put to greater use. Thinking beyond common functionality, maybe you can even use this shelf as a seat…

The second set of experiments are nothing but aesthetic wall dressings. Their titles insinuate the additional meaning: "Grow Plug" and "Single Vase AC." These houseplant retrofits cover up tacky wall outlets while adding an element of fresh-cut or freshly-growing nature to the room.

The third, and my personal favorite, is simply titled "Off." This is a light switch hook designed so that the it only functions as a hanger when switched to the "off" position. The switch is still fully functional, but the added bonus encourages you to think about your actual lighting needs.

Designer and experimenter Scott Amron has performed and exhibited a large portfolio of functionality experiments incorporating basic principles of engineering and physics while challenging their common conceptions. One outstanding project among these is called "Brush and Rinse," which won a Best of Category award in this year’s I.D. Annual Design Review, a highly acclaimed annual design competition. Scott has a B.E. in Electrical Engineering, and is a declared freelance electrical engineer, designer, conceptual artist, inventor, and founding principal of Amron Exptl.

Check it out. His products don’t cost you your shiniest penny, and they will provide your houseguests with a challenging surprise.

Eco-Effective Innovation: Sugar Technology and the Sony Bio-Battery

Who ever thought that asking your neighbor for sugar could carry more connotations than that of baking necessities? Well, Sony is working on a product that will make your neighbor think twice about your consumptive demands.

Sony recently announced their current activity in developing a new bio-battery. The battery generates electricity from carbohydrates (currently sugar) and utilizes enzymes as the catalyst. The sample battery has proven to be able to output 50 mW, or enough to power a portable mp3 player. This is the world’s highest yet for a passive-type bio battery.

According to the Sony Press Release:

Sony developed a system of breaking down sugar to generate electricity that involves efficiently immobilizing enzymes and the mediator (electronic conduction materials) while retaining the activity of the enzymes at the anode. Sony also developed a new cathode structure which efficiently supplies oxygen to the electrode while ensuring that the appropriate water content is maintained. Optimizing the electrolyte for these two technologies has enabled these power output levels to be reached.

The newly developed bio battery incorporates an anode consisting of sugar-digesting enzymes and mediator, and a cathode comprising oxygen-reducing enzymes and mediator, either side of a cellophane separator. The anode extracts electrons and hydrogen ions from the sugar (glucose) through enzymatic oxidation as follows:
Glucose -> Gluconolactone + 2 H+ + 2 e-
The hydrogen ion migrates to the cathode through the separator. Once at the cathode, the hydrogen ions and electrons absorb oxygen from the air to produce water:
(1/2) O2 + 2 H+ + 2 e- -> H2O
Through this process of electrochemical reaction, the electrons pass through the outer circuit to generate electricity.


Since the battery does not require the user to do any mixing or formulating, the process is quite simple and it requires very little of the owner. But, each cm2 can only produce 1.5 mW in the first minute, so the battery has to be quite large. The current dimensions are 39×39x39mm- I don’t know how portable and functional it makes this object, but it is a step in an interesting direction.

The most applicable situation I see for this technology is for remote electrical generation necessities (which puts an interesting spin on neighborly sugar supply). For locations or trips that could not benefit from portable solar panels, sugar is a new alternative. As the design progresses and the technology is tuned, I am sure they will be able to come up with something on a more practical and portable scale.

Again, the question arises about genetically modified sugar due to increased demand of the material. Will we begin manufacturing it in the lab and what will this do to the sugar farmers across the world? These questions are always something to consider with the development of any technology using a finite, consumable resource.

It is although fun to imagine one day giving your cell phone a shot of liquid sugar when it starts beeping with low battery indication… Instead of cords, we will have IVs of liquid sugar lying about our apartment floor with a portal into our computer, our radio, our coffee maker…interesting.

Weekly DIY: Wind Turbine

build it beautifulBuild it beautiful

In honor of the holiday and the American Dream of freedom and exploration, I am going to help you declare an “energy independence” today (at home anyway). Today, we are going to decrease our dependency on finite natural resources such as coal and natural gas used to generate much of the energy we consume in this country. The interesting lesson is that these finite resources are burned to generate steam that drives a shaft through magnets, resulting in an electromagnetic inductive reaction that generates electricity; the same principles on which wind power is generated.

Today’s topic to shout from the mountaintops is how to make your own affordable wind turbine. Did you know that the energy in the wind more or less follows the human 24-hour power consumption cycle? So I’m here to say, lets utilize that wind while we simultaneously use up the electricity.

I have personally not built this mechanism, but being a declared experimental designer, I like to rig things up and love to figure out how things work. Thus, I have reviewed many instructions and debriefed for you an informative and simple process from a Do-It-Yourselfer in Arizona who built his for under $150. If you crave more specific instructions, visit his site or one of the many options at the bottom of the page. There are hundreds of ways to build each sub-construction, so get creative and think about efficiency in weight, size, and aerodynamics.

Without further ado, following is a simple and cheap process of instructions on how to build your own wind turbine at home!

The bare necessities that every wind turbine has in common:
1. A Generator
2. Blades
3. A mount and wind vane to keep it turned to the wind
4. A tower to put it up in the sky
5. Rechargeable batteries and an electronic control system

With that said we will follow these 5 recommended steps to simplify your way to a great affordable turbine.

1. The Generator
First, the heart of the whole mechanism: the generator. An electric generator is quite simple when you refer back to your knowledge of physics. To put it simply, the generator will convert the mechanical energy in the wind intercepted by the blades and into electrical energy. If you want to learn how a common generator works inside, refer to this site. To get the basic principles of electromagnetism, refer here.
image courtesy of wvic.comElectric generator: image courtesy of wvic.com

Generator Shopping:
Many electric motors work as generators, as they function the same fundamentally only in reverse. Instead of outputting a voltage from the crank of a shaft, a motor would crank the shaft from an applied voltage. The only problem is that many motors have to be driven much faster as a generator to reach their rated voltage.

I am told that Ametek motors are the best for home built turbines. The Ametek 99 voltDC, although large, is the best one they make. But word on the street says it’s a hard one to find, so if you can't find the top dog, don’t worry, they make many alternatives as do other companies.
The best advice for motor/generator shopping I can give you is look for a motor that is rated for:
1. High DC voltage
2. Low rpm’s
3. High current

If you’d like to leverage the properties of the different Ametek generators visit this site!

Another great motor I’ve heard a lot about is the MiniGen Motor. Although it doesn’t have a huge power output, it is small and can serve as your hub to attach your rotor blades to directly. It outputs AC power so when you get to the electronic controller stage you will need a rectifier instead of a blocking diode.

MiniGen MotorMiniGen Motor

Once you’ve acquired and decided on your generator we are ready to move on to the blades.

2. The Rotor Blades and Hub

Many people use ABS, or PVC piping. You can carve your own out of wood, which I have done, but be sure to use as light a wood as possible. If you want to get real slick and sexy, you could use styrofoam and carbon fiber, but those materials are neither sustainable nor healthy. A great site to refer to while constructing aerodynamic efficiency is the Danish Wind Industry Association.

With a plastic pipe 6” in diameter and 24-36” long depending on the intended scale of your project. This is what you want to do (scale is set for 24” blades).
1. Cut the pipe into 4 equal parts around the circumference (you only need 3)
2. Cut the blade at the angle you prefer (usually about 20 degrees)
3. Sand the edges to maximize the aerodynamics
4. Next you need a hub to bolt your blades onto (4-6” diameter hub will be perfect) with a hole in the center that will fit the motor shaft.
5. Mount the ends of the blades onto the hub with screws and bolts each 120 degrees from the other.
6. If you can find a plastic half sphere to cover the front of this construction, it will improve the airflow therefore the efficiency of the unit by directing air into the rotor blades.
Image courtesy of Mike DavisHub and Blades: Image courtesy of Mike Davis

3. The Mount

The mount and wind vane are important because they hold all the parts and direct the blades into the wind. The wind vane or tail is the balancing tool of the mechanical energy operation. It keeps the turbine from capsizing, therefore sacrificing harvestable wind.

1. It is easiest to use a 2×4” piece of wood about 35” long. This measurement can be imprecise as long as it fits the motor and is long enough to allow the vane to work with ease, so feel free to use any scrap lying around. Again, it is important to keep this whole construction light. This will facilitate movement of the mount in the direction of the wind.
2. Mount the motor to one end of the 2×4 so that the motor shaft is fully extended beyond the end of the wooden mount. (It is a good idea to cover the motor with something to insulate it form weather conditions-metal electrical boxes work as well as a piece of PVC pipe.)
3. Mount the rotor blades and hub construction onto the motor shaft.
4. Next, Wind Vane: All you need is a rigid piece of material to stand up about 8 inches and extend down the mount about 14 or longer. This is the mechanism that really controls the direction of the turbine. It is very important. Although the rotor blades can catch the wind and aid turning the construction in the right direction, the vane does this with much more ease. (Common materials are sheet aluminum, plastic, or even a thin wood. If you want to go green and creative- find a piece of flashing that’s laying around, cut up an old plastic binder, or cut up the lid to an old Tupperware container. [Note: all these materials are very light].)
5. Cut a groove in the wooden mount just wide enough for the thickness of your chosen vane material.
6. Slide it in. If it’s not tight enough, glue it into place to secure stability and function.
7. Add a weight of any sort to the bottom of the wind vane end on the 2×4. This will be your counterweight to the generator. You can use a lead weight (although not a magnet), a sand filled balloon…

An alternative to this construction is to find a 2 ¼” pipe or something large enough to fit the generator into. Insert the generator. Attach the hub to one end. Cut a slit in the other end in which to insert your wind vane. You can also place your counterweight inside the pipe. This construction is a bit sleeker in appearance.

4. The Tower

The height of your tower will be highly dependent upon your location in this world. If you live amongst many a canopy of tall trees, you will have a lot of interference to compete with. If you live on the plains, the wind will “go whipping o’r the plain” freely and quite low in the sky.

What you need for the tower is a long pole with something that functions as a bearing at the top to allow the mount to turn freely towards the wind. These are the step-by-step instructions from Michael Davis of Arizona who scratched his head at the local home center store over this for a couple hours. I think his solution is quite functional yet the resistance/friction on the bearing could be lower and more efficient.

1. Attach a 1” pipe fitting to the bottom of the generator end of the mount about 7-8” in.
2. Screw a 1” diameter, 6-12” long pipe nipple into the pipe fitting
3. Slip the pipe nipple into a 1 ¼”, 10-20’ conduit (depending on your locational interference).

With this construction you can drill a hole in the 2×4” mount and feed the wires from the generator right down through the pipe fitting, through the nipple, down the conduit, and out to the control system.

4. Find a scrap piece of wood that is about 2×2’. This will serve as your base.
5. Make a U shaped assembly out of 1” pipe fittings and pipes.

The Tee construction will function as a hinge that will allow you to raise and lower the tower.

6. In the center of the assembly put a 1 4” Tee. Insert in it a 1 ¼” close nipple, a 1 ¼” to 1” reducing fitting, and a screw into that a 1” diameter, 12” pipe nipple.
7. Drill a hole in pipe nipple, large enough for the wire to come out from the conduit.
8. Next drill holes 1” in diameter in the base platform that line up with the pipe fittings. This will allow you to drive shafts into the ground to stabilize your platform. The shafts will extend from the earth into the parallel components of the U construction, thus grounding the tower!
9. Attach 4 guy-lines to the conduit about 10’ up. Tie a rope to each line. Anchor each rope 90 degrees from the other in the earth with some stakes. Make sure these are secure, as you don’t want your turbine to come tumbling down. If you see this unnecessary then skip the whole u construction and anchor the conduit directly into the ground.
Mike's Base ConstructionMike's Base Construction

5. The Controller System

Here comes the interesting part that takes a bit of research, but once you do it step by step it all begins to make sense. The controller stores the power created by the spinning turbine and sent down by the generator.

Here are the items you need, what they do, and how they work:
1. First the power sent down from the generator is stored in one or more small batteries.
2. The surplus power is sent out to a larger storage/load when the primary batteries get fully charged, because they will.
3. A 40 amp blocking diode. These are one-way valves that allow the charge to be pumped in but not back out. This prevents the batteries from powering the generator as a motor and spinning the turbine voluntarily. If you use an AC motor you will want to use a rectifier instead. Rectifiers capture the peak and trough of an alternating current. I referred to this earlier in the generator section.
4. A charge controller. The controller monitors the voltage in the batteries and decides where the power from the turbine is needed and should be stored. If you are savvy with wiring up your own electronics this site will show you detailed diagrams of circuit construction and a couple links to help you out. If you don’t want to go there, then search eBay or some of the sites below for a wind power controller. Our friend Mike in Arizona built a fully functional controller, check it out.
5. The cord. If you have an old extension cord, dysfunctional on one end, perfect! If not find some insulated electrical wire with a decent size gauge (¼ – ½”). Attach a couple spade lugs to each end. Attach one to each output on the generator. Then thread the chord through the conduit and connect the spade lugs on the other end to the controller unit.
6. A 120-volt inverter. This is very important because it allows you to use the DC power generated. You will connect this to the battery load unit. It converts the 12V DC power stored in the batteries and into 120V AC power. From this you can plug in any household device you would plug into the wall: your computer, a toaster, a lamp…
Going Further Bonus: you can get a digital or analog computer-interface multimeter (can be found at Radio Shack or your local Electronics supply shop) that will connect to you computer for data logging!
Ahhh, I think I pretty much covered it all. Now that you have all the parts put together, you have yourself a beautiful turbine that initiates or enhances your independence from the communal electric power grid!

I challenge you to get as creative as possible in your project. In my research, I saw project constructed of 100% reused materials. It isn’t difficult, you just have to dig a little bit deeper. Maybe the shape or material you need is in that object you just put in the recycling bin, or even better in the trash. I also saw collapsible and portable turbines to take camping and on road trips. Here are a couple sites that I hope will inform and inspire your project:

Science Fair Wind Generators
Minigen
Otherpower.com Discussion Board: My First Wind Turbine
Otherpower.com Discussion Board: Wind
How I Home-Built an Electricity-Producing Wind Turbine

Also, get creative on how you hook up the power supply. You could connect it to your water heater or your electric oven. You could rig it up so you have multiple removable secondary loads. Use the secondary battery packs to take inside and power your computer throughout the day or your telephone (but don’t forget to take the inverter too). If you think you are harvesting enough power, look into connecting it to the power supply in your home. If you are not quite there yet don’t worry, the experiments have just begun. Have fun, and please let me know if I can direct you to additional information.

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