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Concentrated Photovoltaic?

I have converted a Satellite TV dish to a solar concentrator. Now, how do I generate electricity from the concentrated heat? Is there any photovoltaic available for this?

Question by thinknirmal    |  last reply

Solar Concentration?

I wonder if anyone has tried this, using either a solar cell, or joule thief powered LED in something like a torch head fitment  with a solar cell capping the end of the torch head such that the maximum amount of vsible light is falling on the solar collector and none is going any where else. Although direct sunlight may be ok to power a PV, because of local weather it could still be described as diffuse and tricky to get a constant intensity of light where it is needed. If it were possible get a gain in efficiency this way it also could mean that you are not constrained by the amount of area you need to lay out panels to catch sunlight, the collectorsand lights could be stacked vertically in enclosed units.Apparently PV'sare most efficient in the visible light spectrum which reduces concerns of radiation (UV or IR) If efficiency and power could be increased in this way small units could be joined in series or in gradually  increasing size to power requirements.

Question by Nowandthen    |  last reply

concentrating fish oils?

Is there a way to concentrate fish oils? or even an effective way to "harvest" fish oil?

Topic by ledzep567    |  last reply

Copper tape for thermal concentration

Has anyone ever used copper tape to concentrate heat on an object to obtain a uniform higher temperature?   I've been doing some studies in the recent past that suggest polished copper foil is a good reflector of infrared energy. It is not as good as silver, but I don't think it would go over well to use silver in any sort of oven or kiln.  I used to think good ole aluminum foil was good for heat, but it turns out it is only good for stopping heat.  I've thought of using the instructable on the waffle iron or make one by way of a bread toaster, but will most likely not be able to go through with it.  The copper foil is the same type found at stained glass craft shops. 

Topic by jmikronis    |  last reply

What is sunlight concentration ratio?

I was trying to figure out the optimum size of solar cells for a various light concentrations and then I came across this term. Does anyone have an idea... what does that mean?

Question by raishikoh    |  last reply

Oxygen concentrator on power inverter in car?

Can I run an O2 concentrator on a power inverter in my car? How do I figure it out?

Question by NotAPot2PN    |  last reply

How does one measure the level of carbon dioxide in the air?

I'm planning to see if more Carbon Dioxide in the air is good for plants, but to do this I need a way to measure (moderately accurate readings) of the concentration of Carbon Dioxide in the air. Money isn't too much of an issue, just not too much (over $100 is too much) but it needs to be quick and easy to use. Ideas?

Question by Kryptonite    |  last reply

How do you concentrate citric acid? Answered

I'm making this thing, and I was wondering if concentrating the citric acid (from calamansi (Philippine lemon)) would increase output. My friend suggested boiling it, but is there any other easy way of concentrating it? If not, then let boil.... For the meantime I'll boil it to check if it works. If results come back positive, I'll delete this question. If results come back negative, I'll let this question float around instructables for a while. (Please do help me in putting this in the right category)

Question by nutsandbolts_64    |  last reply

Open source tracking solar concentrator is go.

Meant to update on this here a while back. For nearly two years now I've been developing the prototype for a solar energy device makeable from scrap and recycled materials, using very basic tools and skills. It's now working, details available here: Facebook group here. This has been possible largely due to the awesome help and support I received through this site. Currently I'm back in New Zealand, preparing the first free workshop on the device's construction and use, taking place the three weekends after Easter at the Tui community, Golden Bay. Then back to Europe for the summer and tour this thing around. Animated tutorials will be available at as soon as I find a spare second to do them and finish the website. My God I'm busy.

Topic by SolarFlower_org    |  last reply

what is the equation i should use to dilute 50% hydrogen peroxide into lower concentrations? Answered

Hello, i just got some 50% hydrogen peroxide, from my local pharmacy because they were out of 35%, plus for some reason 50% is free. anyways, i want to know whats the equation for finding out how many ml's of water i need to use to dilute a solution toa certain amount, as i want to use the 50% peroxide to make 30% , 22% and 3% peroxide. now ive looked on google and i couldnt find a thing , and if i did by chance come across it, i didnt understand it. what i want to know is how much distilled water will it take to convert 100ml of 50% hydrogen peroxide to the above concentrations, or if possible, could someone please give me the equation for converting any concentraion to any, please! also, whoever answers my question and solved my problem entirely will get a best answr i promise!!!

Question by oldmanbeefjerky    |  last reply

midflex idea bulb

I was in my quantum class today taking in some nice Schrodinger equations. The professor was having a hard time figuring out which students were understanding the material. I thought to myself, "Wouldn't it be nice to have a consistent way to show the teacher you understood." So then it hit me... why not have a classic idea bulb on top of a hat. You could push a button and it would light up. Thus indicating to the teacher that you understood the material. Simple enough, but kind of annoying to push a button every could of minutes. Why not use the new Mindflex toy to gauge your understanding of the material? The user could wear the headset like usual. Instead of controlling a ball like in the game, a sudden decrease in concentration (the realization of an idea) would turn the light bulb on. The electronics should be simple enough. It would obviously be better to use an LED instead of an actual light bulb. I would build it myself, but I don't want to spend $60 on a mindflex game. What do you think? Elijah

Topic by Mirage_662    |  last reply

'Revolutionary' CO2 maps zoom in on greenhouse gas sources

Researchers now have a better view of where carbon dioxide is being emitted thanks to Vulcan, a research project led by Kevin Gurney, an assistant professor at Purdue. This map shows where CO2 is being emitted in the continental United States in 10-kilometer grids and combines data from sources including factories, automobiles on highways and power plants. The map offers more than 100 times the detail of previous inventories of carbon dioxide. The image displays metric tons of carbon per year per grid in a logarithmic base-10 scale.more at Physorg

Topic by ewilhelm    |  last reply

how can i concentrate of a bulb light at a point ?

I have a bulb ( pic is attached ) and for some experimental work i have to concentrate its all light at a single point. can anyone help me that how can i do that ??

Question by m_uamir72001    |  last reply

Air sample analysis for the concentration of CO2/Carbon Dioxide? Answered

I'm working on a high school science fair project which concentrates on the CO2 emmissions of automobiles and anlyzes two methods of filtering CO2 from car exhaust. It's really a pretty simple project - except that i don't have a Carbon Dioxide monitor. Online they range from $200-800 and i've contacted the enviornmental department at a local university to see if they can help me. I'm still waiting on a reply but i'm wondering if any of you guys (or gals) have any ideas on how i can find the concentration of CO2 in car exhaust.

Question by Aaron Cole    |  last reply

Solar tracker and concentrator: lots of things getting finished.

I'm kind of entering the home stretch on my year long (so far) solar energy prototype, getting the various components finished off and thought yall might be interested. Things such as: Parabolic troughs! Rather efficient water wheels! Low friction worm drive gearings! World's simplest (probably) heat engine! And much more. All made mostly from scrap. I'm posting updates and media to my blog:

Topic by SolarFlower_org  

Quick and dirty parabolic dish solar concentrator design!

I do not have one.       I was hoping YOU could help me make a quick choice!   Basically I want to go to the store, buy an 8 by 4 corugated plastic sheet, cut it in petals, stick aluminum kitchen  foil to it (as few wrinkles as possible) and have as rigid a parabolic HALF dish as possible.   Then I mount it in my equatorial mount frame and test it.   It gets a bit harder because the dish is not exactly a half. Some extends a bit past the center of the dish. Here are some of the issues and choices.  Do you cut along the corrugations or across them? Do you do petals radiating out from the center  or is it better to do the thing with cones? Like in the picture in the link Cones might have a problem due to the corrugations not being in line with the shape that I make. so it might warp in strange ways. Is there an alternative to the corrugated sign plastic sheet? BUT they might work because I can guesstimate a not perfectly round dish more easily than with petals.. I think that something with a focus about 6 inches wide would be sufficient for me. It has to be rigid and light as can be too.   What can I use as umbrella splines to make it keep its shape? Thoughts and suggestions would be greatly appreciated. I might have a day off tomorrow so get those suggestions in quick as you can! Thanks Brian

Topic by gaiatechnician    |  last reply

Concentrated Solar Power Hits Pop Culture in the Best Way

Check out this graphic of concentrated solar collectors on Saul's new skateboard. My first skateboard had a dragon sitting on top of a pile of human skulls. We've come along way, I guess.

Topic by ewilhelm    |  last reply

is it possible to obtain pure concentrated kno3(potassium nitrate) in the us,legally?

Im making,well trying to make high power two stage rockets and need pure kno3

Question by dab2000100    |  last reply

Where can I find a CO2 sensor that will allow me to measure the concentration in a small space?

I'm doing an experiment where I'll be burning a candle in a closed box, and measuring the concentration of the carbon dioxide in the air. I need to be able to record a value for the concentration of the CO2. What's the best way

Question by suvayanr    |  last reply

In alluminium etching process what concentration is used , i want detail and is there any easy way in etching process ?

Our company is moulds making company we are trying to make chemical etching 

Question by design-centre    |  last reply

Is it possible to either create a concentrated brine or to separate sea salt from sea water by centrifuging?

If it is possible, how many RPMs would be required to achieve such result? Thanks for any help! James.

Question by SeaCub    |  last reply

Electricians Qualifications and how we can get them

Electricians are those who concentrate in creating, working on and designing electrical systems. There are specific types of Electricians who concentrate on certain types of electronics work.

Topic by supreet  

GIBBERELLIC ACID MIX? When using gibberellic acid for miracle fruit tree,what is the concentration mix ? Answered

I recieved my gibberellic acid kit from united nuclear and the bottle say's 1 part acid and 1 part water to make 50% stock solution.the mixture sheet say's how to mix for 250 ppm and 500 ppm, which is the right mix? the spray bottle is marked for the 2 different concentrations of 250 ppm and 500 ppm.Which is the right mixture of these 2 or is the 1part acid and 1 part water the right mix? i am not good with numbers or measurements, so please be spcific! thankt you !!!! As requested here are the instructions for the mix.The mix is to be used on seeds from the miracle fruit tree!

Question by GROWFAST    |  last reply

How much surface area of mirror would you need to boil 16 oz of water in less than 5 minutes using concentrating solar? Answered

I'm working on a coffee machine powered by the sun and need a little help with the mirror sizing. How much surface area of mirror would you need to boil 16 oz of water in less than 5 minutes using concentrating solar? Can I do this practically with a dish less than 1 meter square? If I get this to work I'll post it for sure.

Question by robbtoberfest    |  last reply

Chemistry Question

I am trying to make a small amount of silver fulminate for throw snaps. I am using a recipe from a very old book and it says I should add 70 minimums of concentrated nitric acid. Any ideas on what a modern measurement of a minimum would be, and where I could buy concentrated nitric acid?

Topic by Sedgewick17    |  last reply

"Does rubbing alcohol affect plastic, how and what types?" Answered

I am hoping for someone to point me to research information. I am asking specifically about cleaning plastic water bottles and ice chests/coolers with rubbing alcohol. I was told that alcohol can deteriorate the plastic but I was hoping to know what types of plastic are affected by what types and concentrations of alcohol. Thanks

Question by AthleticTrainer    |  last reply

I accidentally invented a device to collimate any light source into a concentrated beam... what should I do with it?

I've been umming and ahhing about what to do with this for the couple of weeks since I accidentally invented the thing (I was working on a solar energy device), and I thought you guys may be your usual well-spring of help and advice. Basically I seem to have designed a device which will collimate an extended light source. Any light source. So you could, for example, turn a 100 Watt light bulb into a 100 Watt laser. Or a square meter of sunlight into a kiloWatt. I haven't made it, but simming on the computer gives an optimal blow out rate of about 1/2 meters per kilometer, so over a range of meters or tens of meters it's pretty much as accurate as a normal laser. The only upper limit I can see on how much power you could put through this thing is when the materials start melting, which would probably be pretty high. There's really nothing fancy about it, it's just a shape. You could print it out easily on a 3d printer and fill it with some kind of settable glass for the total-internal-reflection. It would weigh about as much as a 2 litre bottle of water and be about the same size. I was concerned about it being weaponisable, but even at a kiloWatt the lethal range would probably be less than 100 meters, in which case you might as well just get a gun. I don't know if anyone's already done something like this, I can't find anything online, and people kept telling me it was supposed to be impossible. So, um, yeah...

Topic by SolarFlower_org    |  last reply

Can saltwater be desalted by freezing it?

When putting the saltwater in the freezer for 12 hrs, will it make the concentration become lower than before?

Question by The Acid    |  last reply


I want to make a biosensor of for glucose measurement. The aim is to develop a method for blood glucose measurement by measuring the impedance of glucose solution of various concentration. Suggest how can I measure impedance of a glucose solution and study variation of impedance with the concetration

Question by utkarsh046    |  last reply

Does anyone know how to dry a liquid to make a powder?

 I want to make stevia powder out of a concentrated stevia liquid? To store it longer and to use it in dry tea mixtures and so on.

Question by hugenott    |  last reply

solar light to laser beam ?

Hello, would it be possible to concentrate solar light so to form a laser beam ? In other words would it be possible to apply laser light principles to basic solar light with the help of optics of some sort ?

Topic by gabdab    |  last reply

CO2 analyzer (sensor)

Dear friends My research topic is about designing a chemical reactor for CO2 capture. I have designed an experimental reactor and I need to measure the concentration of CO2 in the outlet of the reactor. Accordingly, I need a CO2 analyzer (CO2 sensor) that would be able to measure the concentration of CO2 and record it in the computer. I have searched google, but I have not found too many products that can be used in my research. Could you inform me if you know any CO2 analyzer or sensor that meets the following criteria: 1) I need to record the variations in CO2 concentration in short periods of time, for example every 20 sec. The analyzer should have a data acquisition system or can be connected to data logger to record the data in the computer. 2) I need to change the flow rates every time I begin the experiment. The range of flow rate will be between 1 to 5 Lit/min. The flow gas usually contains 25% of CO2. While I appreciate your kind attention, I look forward to hearing from you soon. Best regards Saeb

Question by sbesarati    |  last reply

Knex vehicle project ideas?

I am quite stuck for fresh ideas for knex vehicles so I was hoping anyone could give me new ideas!! or you could just give me a few features that ive not already made to concentrate on. ^_^

Question by jingo69    |  last reply


Is it possible to take a low heat spread over a large area and convert it into a high heat in a small area? For example a normal fireplace can't melt cast iron, but 2 or three create enough energy. Could you concentrate that? (thats just an example, I have a much more brilliant plan) Thanks

Topic by LinuxH4x0r    |  last reply

Carbon emissions still increasing despite recession

With the whole economic kerfuffle going on you would've thought that there would be less carbon going up into the air. New studies show that emissions continue to ride, however. The data is collected and analyzed by scientists from the Norwegian Polar Institute and Stockholm University. Researchers found that during the first two weeks of March, the concentration of carbon dioxide in the atmosphere rose to 393.71 parts per million (ppm), up from 393.17 ppm during the same period last year. John Stroem, a scientist with the Norwegian Polar Institute, told Reuters that looking back at data gathered since the 1980s, the increase in carbon concentration levels seems to be accelerating. Carbon Emissions at All-Time High Despite Economic Slowdown

Topic by fungus amungus    |  last reply

Missing Instructables :(

It hasn't been a month since I've posted my last ible and I won't be able to post ibles on a regular basis for the next few months, but I already miss instructables :( . I'm trying to concentrate on my studies for a while but I can't. I really wanted to participate in the Zombie contest (I'm a huge fan of 'walking dead!), but it takes time to collect the materials, make something, document it to post an ible, I hope there will be more Zombie contests in the future. Anyways, just wanted to say, I'm sure I'm not the only one and I would really appreciate any suggestion and consolation so that I can stop feeling sad about missing instructables and concentrate on my studies for some time. Can't wait till my exams are over!

Topic by Muhaiminah Faiz    |  last reply

Is it possible to extract alcohol from hand sanitizer? Answered

OK, so the main ingredient in instant hand sanitizer is ethyl alcohol, which is a perfect fuel for a soda can stove.  I have tried using the sanitizer straight but it leaves to much goo behind.  When stalt is added to the hand sanitizer it turns it to liquid and leaves white floaty things in the liquid(glycerol?).  These can be filtered out with a coffee filter.  This leaves a more concentrated solution (which still dosnt burn well)  and it has salt in it. What I want to know is how I can extract the alcohol to at least 80% concentration.  I don't have a still (and dont want to make one).  Any ideas?      

Question by junits15    |  last reply

how easy is it to make a hho cell for your car or truck?

i know that using a electrified cell you can separate the hydrogen molecule from the oxygen to produce a more concentrated mixture for combustion, is this simple enough or safe enought for a hack to do???

Question by dannybroderick77    |  last reply

making a very powerful sun beam

Hi there,  I  have a question and perhaps you could be of help to me, So my question is ,  is it possible to use cheap Mylar blankets(parabolic form) to concentrate the sun light, so as it would be able to cut through metal. My idea is to use 3 Mylar sheets each  1m square  which will reflect the light towards another  one which will work as a collector and then further concentrate the light to about half a millimeter.  Doing the math (0.5mm²/3m²) is more than 16 million (ok there  will be a lot of loss , lets say 50 percent). The question is, is this worth trying cause i don't want to waste time and money on this. So if someone knows why this wont work , it would be very helpful. thanks in advance

Topic by Z3r01f1n1ty    |  last reply

Help identifying an unknown object?

Any idea what these are? I think they’re from a surveyor possibly around the 1950-60’s but not certain what they are. They’re appear to be made of plastic or lexan and don’t appear to have any optical qualities. The three pieces are concentric in size and have a goove on one side. They came in the leather pouch shown in the photo. Thanks in advance!

Question by ericdube  

homebrew distilling question is this safe-see picture. Answered

Hi, I saw instructions about homebrewing in a book i downloaded and have now lost. The picture shows the essence of it. Is this safe? would it actually concentrate the alcohol? the idea is to keep topping up the mash with sugar and water, using high alcohol tolerance yeast. would distilling the product of this make a safe product? thanks.

Question by djsc    |  last reply

Happy New Year!

Just wanted to wish everyone a Happy New Year, have fun and I hope that you all prosper in this new decade :) Maybe we can share some of our resolutions? I'm going to start to concentrate more on work than playing video games. I hope 2010 will be a great year for you :D

Topic by FrozenStar    |  last reply

I really need to make a very complicated electromagnet ... Is anyone smart enough to help me ?

I really need an electromagnet that can/ is : + pull a very heavy metal from above ( which means the electromagnet has to be very strong and very concentrated in one direction ) + a energy-saver or uses little amount of energy Guys , I need some helpful comments right now . Please help !!!!!

Question by hannahcarts    |  last reply

what do you think of human evolution ?

You may thing  this sounds weird or stupid but i think we can evolve  like if your falling of a building if you concentrate and focuse on evolving like fly it will trigger and make you a mutant it just all a trick of the mind you control it doesn't control you.     

Question by the hellphantom    |  last reply

Mirror Paint? Answered

I am trying to make a death ray with a parabolic mirror. I have tried a mylar space blanket but it wasn't smooth/reflective enough to make a concentrated beam that burnt anthing. I was wondering if there was any such thing as mirror paint. by this I mean a highly reflective paint. If anybody knows about this or has any other reflective ideas I would apreciate it. Thanks.

Question by nurdee1    |  last reply

A small doubt regarding modulation

Hi guys! I have a doubt regarding modulation process, more specifically regarding the spectrum. I understand the spectrum of sinusoidal signals, the amplitude or energy is concentrated at a particular frequency, say Fm, and hence the delta functions. But why is the spectrum of the unmodulated message(original) signal always displayed only in the shape of triangle? I have been going nuts over this question.  I have attached the images just in case

Topic by charmquark    |  last reply

Vibra-bots New Group!! "Vibra-bles"

Vibra-blesA group dedicated to all things which vibrate to assit locomotion.This group shall hopefully provide a location for you to proudly display all your hard work.Predominatley we will be concentrating on Vibrating "robots".However if Vibration is key in your design it will also be suitable.Hun fun and feel free to post your images/video of your experiments.Good Luck!Vibra-bles

Topic by Lftndbt    |  last reply

Cutting brass sheets: replicating Christmas ornaments

I'm looking to replicate a brass ornament for a dear friend. The ornaments in question are similar to these ( Do you guys have any suggestions on how to get the precision for the concentric rings as well as the detail inside? I thought about using a Dremel for the detail work, and snips for the outside, but I'm having trouble coming up with a solution for the rounded rectangles.  Thanks!

Topic by RamboBrite    |  last reply