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  • LOL, are you saying that politicians and election campaigns are nothing but hot air anyways? :))

    This is awesome, Dan and Denise, I like your ideas! :))

  • You do know that its only number 2 heating old that most home's use and its a lot but for buildings I know that number 4 and number 6 are up to 80 cent a gallon number 6 a year back was only 63 cent but number 4 and 6 burn dirty so you will see black smoke when you first start you're boiler up. NO HOME SHOULD USE NUMBER 4 OR 6. Its not for you or your units

  • Chk the solarventi allredy uses ure ides , and its behind a glas board and uses a solar driwe fan at back side is used hole and filtration than one hole in wall too press in hot air....

  • hahahaha one great miss the vacuum cleaner adds heat iff im not wrong,,, engine cool off?

  • Corrugated plastic is available in several thicknesses. It looks like you are using the cheapest stuff. There also is a product that is approx. 1/2" thick corrugated plastic with an aluminum facing. The corrugated plastic has larger channels. This product is also available in 10' sheets. It's called alumacorr. Quite rigid. It is mostly a sign product. Your project is very interesting.

  • Vote for DAN!!!

  • Does anyone knows of any safe chemicals that heat up to 175+ degrees when motion is applied. If ammonia, sulfur dioxide, and non-halogenated hydrocarbons such as methane can be used as refrigerants when motion is applied, what chemicals can be used for heat when motion is applied? Contact RF at rf_countrychristian@yahoo.com

  • If you took a sheet of corrugated steel and then laid a flat sheet of steel on it a "spot weld roller" could be fashioned. A wheel rolling in the trough of the corrugation and a second wheel on the back of the flat sheet would press the sheets together. With a ground applied to the sheets and a welding voltage passed thru the wheels a welded seam would be made. The assembled panel would gather more heat especially if painted flat black and would be VERY durable.

  • looks like you have a lot of fun dan,at least it gets people thinking green and you get to impress your good looking woman, good stuff !!!

  • Why not use black pvc piping cut down a scribed line mount the board

    pvc cement an intake manifold tube on the bottom a hot air exhaust tube out the top and silicon glue glass panes to the front and back.

    Seems faster, easier to construct, and uses the power of greenhouse collection to capture more heat.

    Love your videos. Keep up the great work.

  • Dan, do you have any tests or any links to tests in regards to efficiency of various "forced air" heaters? Pipes, coroplast (corrugated) cans and the like? Id like to build a couple of these things but I really cant afford to do experiments that have already been done. I know this is free energy, we should all be using it.

  • there arso alumium panels with the same texture, but they are very hard to find

    Plastic will warp over time I guess, but I can be wrong

  • when it start to smell burny it means your carton is carbonizing?

    Nah I will use a a metal board

  • Dan - I like the idea of retasking the large political signs. Hmm...finally some of the hot air that goes to Washington doing some work for a change.

  • The amount of energy showered upon the earth from the sun, even on cloudy days, is pretty amazing.

  • This was inexpensive, didn't require fancy expensive tools, and we didn't have to drill holes in our homes walls. At night we simply turned off the fan (some didn't have them) and closed our drapes. Any cold air seepage that occurred would have happened anyway with the existing windows. When the hotter months started to happen, we just simply pulled the units out and stored them in our garage. When cold weather returned, we pulled them out and put them back in.

  • We made two holes, one at the top (hot air outlet) and one at the bottom (cold air intake). Hot air rises naturally, so having a fan is optional. We found that having a fan at either the top pulling air, or one at the bottom pushing air made for a higher rate of airflow into the space. However, even without a fan the air still moved into the living area. Our box with cans, got up to 134F. CONT>

  • We researched a Trombe Wall, along with the popcan designs. We could not put holes in our walls, or put anything on the exterior of our home. So we decided that we would use some foam insulation, and build something that would slide into our already existing windows from the inside of the house. Our windows are double pane, and have to sections. One that moves, and another that is stationary. We built the foam boxes to fit inside the stationary part. CONT>

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  • you need solar panels for your air flow, otherwise the money you save for heating goes to running your fan. have you tried the same thing but with pop cans? works better and in some cases dont need a fan or air flow.

  • 50-50 linseed oil and paint thinner

    instead of thompsons good instructions

  • 50-50 linseed oil and paint thinner

    instead of thompsons

  • hung my panel between my windows on south side of house, rigged teh input/output into a panel that can fit snugly into the window opening when it is raised 6in. rigged small solar panel to open the vent when sun is on it. much better solution.

  • try aluminum cans

  • use the parabolic mirror to heat steal sheeting witch indirectly heats the cardboard. let natural convection take its course from there. for a winter application keep the mirror out side, just a thought

  • This is really awesome. It's inspired me to think of using coroplast to build a heat exchanger and how I would chimney the output to use the natural convection to move air through this kind of heater. Again, awesome.

  • Put a solar powered fan on it.

  • She is so fuckeable, .. trust me i would paint everything green, for a day with you :)

  • have you tried it in winter. you tested your device in warm and sunny conditions. i really can't see this working when its cold and/or just a little bit cloudy. then you're gonna have yourself a nice air cooler, which i suppose is not a great thing in the middle of winter.

  • @etlamphil Forced air heaters need 50% sunlight or greater. You do not run the fan at night or when it is cloudy. Just clear sky cold days. They work well.

  • @etlamphil Don't forget that solar air heaters work on raising "ambient" temps...the air in the unit is the same temp as your house...when the sun hits it...it raises the temp inside the unit. Winter has less solar radiation...but the unit is still capable of producing good supplemental heat even then. A fully sealed insulated unit is the secret...and managing the heat loss through the clear cver is the real concern.

  • If you have a sign shop nearby, they usually have scraps of corrugated plastic.

  • how do you know it's not the vacuum motor that's raising up the temperature...

  • Because a vacuum only adds 1-3 f at most. Place your hand next to a shop vac exhaust.

  • @GREENPOWERSCIENCE ive read that installing a passive hot air furnace on the inside of your home gives you no thermal advantage? is this true? if so.......why?

    thanks.....and keep up the great work!

  • @anatrakya Why would he go through the trouble of making all this If it's just the shop vac? lol.. I'm just curious as to why people such as yourself; make stupid remarks about everything?

  • Thanks man , you are a smart guy ., amazing stuff

  • instead of using wood how about pvp pipe with caps on the ends then you can paint it black so it can also help heat up the air

  • your testing the heat out in the heat

    that thin piece of cardboard would NOT work out on a cold wintry day and you have no insulation and the air flow threw it would freeze up, and there is no air volume this means the air goes in one end and out the other end and has no real time to let the heat build up. with thin plastic you said at the end of your video and cardboard theses are 2 items that can't handle heat and would not last

  • @TheEZhexagon coroplst lasts 5-8 years for a $17 sheet. Also has 3 x the volume of 200c cardboard. Coroplast reaches 137 F in direct sunlight 25 F outside temp, on glass insulation, with glass it goes up to 167 F. The small channels transfer 80% of the heat at 30 Cubic Feet Per Minute. Coroplast is rated at 250 F. Also additional black spray paint extends UV to 7+ years.

  • @GREENPOWERSCIENCE - Dan, I just checked with a local plastics supplier here in Des Moines, Regal Plastics and a 4'x8' sheet of Black Coroplast is about $19.

  • @TheEZhexagon Go back to english 101 and learn it all over again.

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  • Would a computer fan hooked to a cheap solar panel do the job?

    Would simple convection current be sufficient as cool air drawn in as air heated?

  • Yes, the cardboard chambers are too small but coroplast will work perfect.

  • lol Yea I'll be sending a upgrade vid based on all the info you gave

  • Very cool vid .I can take this to so many higher levels.

  • haven't read all 191 comments, so I don't know if this has been mentioned yet or not. If you have the inlet at (let's say) the top left corner and the outlet at the bottom right corner (kinda like an automotive radiator) it should equalize the airflow through the pannel quite a bit. Thanks Dan, good stuff! Keep it up!

  • If you try something like this, you probably want to try a solar powered fan to eliminate the electric use (and to cut off air circulation during night) If your air inlet to heater is from lowest part of room, it will be most efficent as you will heat the coldest air in the room, it will pull heat from the top of the room down that way. (Keep inlet and outlet some distance from one another in the room.)

  • hey Dan , this is a good idea. the narrow passageways of the cardboard makes it a fast heat drain seeing as it is easier to heat small volume large volume. the large surface area denotes larger wattage. so in my analysis of this, it should keep the temperature flowing quite constant. try spray foam on the back for thermal retention , and a thin non shiny plastic film for endurance on the front surface . and then a layer of plexiglass over the unit for weatherproofing and heat losses.

    MUDDy

  • 1. Air blowers can use a lot of electricity, a sculpted inlet/outlet approach will be needed, or at least the multiple port design mentioned, to minimize air flow resistance & blower size.

    2. The channel material is a good conductor of heat, so there will also be heat loss on the far side, so insulation with a radiation barrier/reflector (aluminum usually) should be applied, with the reflector directly against the channel material.

  • Ya the vacuum blower air would be warm from the motor and get warmer as the test went on but still a great idea. It'd be nice to see what it would produce in cold clims. It would be sucking cold air in and may cool the unit too much. I would be tempted to put a dimmer on the vacuum to slow it down to a low purr.

  • if you setup pvc or abs plastic frame it can be sealed to the plastic cloraplast with its own glue. one of them should stick to the signs. weather proof to boot.

  • does this panel will be enough to heat one 12x12 room?

    for at least 5 hour a day ?

    how much cost a 4x8 sheet of COROPLAST.

  • HI,

    A BLACK SHEET 8FT X 4 FT COSTS $20. Spray the black sheet with flat black spray on the sunny side up. This acts as a UV barrier and extends the life of the sheet by 1-2 years.

    Yes, this will heat a room + 20 f that size depending on insulation, ceiling height and outside temp. For very cold climates, add a glass buffer. Make 2 or 3 smaller units as 4ft x 8ft glass is expensive and impossible to work with.

    Smaller units can be chained together.

    Dan

  • You know, vacuum exhaust is hot.

  • My parents lived in Denver & had a south facing front door that was painted black on the outside. My mom, in the middle of winter, could heat their entire livingroom & kitchen with that black door! She opened it about 1/2 was and blew a small fan that direction. On a sunny day you would literally cook if sat anywhere near that door! She could shut off the furnace on a sunny day. Of course the bathroom was a little chilly but they didnt bathe until night & furnace was kicked back on. CHEAP

  • what type of flat black paint that you use to absorb maximum amount of solar radiation?

    Thanks

  • Hi,

    The best paint is a $1 a can enamel from LOWES hardware store.

    It comes in a white tapered can. Walmart Flat black is horrible. Does not cover, but their Gloss black is excellent.

    So Gloss black, walmart or Lowes

    Flat Black Lowes

    Other countries, try the lease expensive first.

    Thicker coats reduce efficiency transfer.

  • What about the temperature rise in the blower? If you run continuous like that in the sun it gets pretty hot!

  • BUT on the other hand. It isn't very efficient. With all that power you just used to force the heat through the cardboard, you could just run a space heater...... ????? What am I missing?

  • The vacuum was only for testing. A solar blower fan would do the trick.

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  • Will deteriorate over time. Humidity will be a serious problem. Corrugated metal roofing will work as well and last far longer.

  • 5 stars. Great work, just love it !

  • Why does he always take half the day to rattle on? Look at this one; 16 1/2 minutes; for what? He could easily cut times to approx 1/4.

  • I though it was great ,,, spray paint is bad for the environment though

  • Bad for the environment?.......You are one of the same idiots that say that there is global warming and your very own BREATH being exhaled causes global warming because it's carbon dioxide and is bad for the environment. TREES NEED CO2. They scrub our air for us. No CO2, no trees. You enviro-terrorists are morons. I always wondered when the Government was going to start taxing the air we breathe. I guess that question is answered.......People like you are the problem with this world.

  • Did it solve anything by name calling?

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  • One other thought

    You seem to be depending on all the heat collection from the corregated tubes, which seems to be working. If the sheet is in a hot box with the plastic cover about 1/2 inch over the corregated material, you have additional heat on the surface of the corregated material as well as in the tubes.  You might want to run some air over the top of the corrgeated materilal too. Need to do some temp tests to prove this out but if it gains an increase, wowo.

  • This material was a nice catch. HOpe it tests up to expecations.

    One point.....

    your mounting is a great idea, that is the end of the corregate against a saw blade space. The single hole is limiting, though you did get a fair air temperature.

    Make a plenumn so the air pressure can spread over the entire end of the corregate. Make one for the discharge end too. Use at least 4 to 6" vent pipe and test that. I thnk you will see a marked improvement.

    JAO

  • i see it it says vote for DAN LOL i saw it!!.

  • It was originally longer. If you notice the sound gets off at the end. Videos longer than ten minutes had an upload issue back then. It came out as a flash, unintended subliminal message. Wish I would have put "Give Dan Money" :-) Since the video got featured I just kept this one up.

    Thanks for noticing.

  • hahaha - dont give the game away! put that in your next one for a laugh... if you already havnt ;D. cheers

  • what was that flash of a sign at 1540 - 1550?? brain washing, subliminal messeging?. not done that well. oh the heating idea is good, so simple but brillinant

  • This Sounds like a nice system, but a few things.

    (1) Will it work in the winter?

    (2) You probably should place glass over it to increase the Available heat.

    (3) U said more then one intake, but perhaps more then one Exit would do good, too.

    (4) What about snow?

    Keep running with your Serendipity, It sounds useful.

  • I would have done the intake in bottom left corner and the exhaust at the top right corner, so all possible path from intake to exhaust are the same lenght, so you use all the surface more efficiently.

    with holes in the middle you only use the middle of the board

  • hi, everything great. i would do 2 things different:

    1st measure air temperature in and out, because vacum cleaner also heats air ~10 degrees i woud guess.

    2 for better air circulation balancing i would do a plastic pipipe collector. Cut pipe like (C------) put silion to seal. Now pipe of 50mm would be perfect to even the flow.

    i know , because i am HVAC engineer my self

    i give you my personal 1000% of aprooval because people like you never stops exploring limits. keep it like that

  • The problem is storing hot air. Where does it go? During the the sunny afternoons it would useful. I'll have to try it next winter with some left over political coroplast signs I always see polluting the enviroment.. My windows face south and west. It can be in the 50s here and the sun will warm up my house. Anything colder and I need a heater. I'll try it next winter. Thanks

  • in south america are many poor areas in the andes were is cold but sunny or enough sun light for long periods of the year .totally useful here.

  • I didn't get the purpose Winter time it would be good for sunny afternoons, but that's it. My heater only comes on at night or on cloudy winter days. Exactly when this would be needed, thus not useful. Coroplast breaks down in the sun after a couple months too.

  • Coroplast lasts about 3 years if you use a flat black enamel spray. Many people have cold days with the sun out. Not a perfect solution but worth the effort. Works for water too.

  • Coroplast the same material used in construction sites to protect floor and wall surfaces?Its pretty tough.I have been watching some videos about 'solar can heaters' and I was thinking, you could use this material as a backing and take advantage of the heat it can pass up the channels in addition to your cans,how about narrow copper tubing up the channels?Im in the UK i plan to build something along that line -if i can save ANY fuel bill even on odd days I will be very happy. Bravo GPS :)

  • The point is the amount of energy you can get from the sun. When your power is out for three weeks in the winter please make a video of your "heater". It will really be cool to watch, once the power is back on for you to upload........ no pun...........I am still using my solar panel and it has cut my heating way down....265watts vs 3000watts you do the math.

  • Who needs a heater when its over 80 degrees outside anyway?

  • gope23 where can I see your system

  • A shop vac is going to consume much more electricity than what you are saving. The vacuum was also probably generating some of the heat too. I would have used ABS/PVC type pipe on the ends to better distribute the air, and set the array vertically in order to try to get gravity to get the air moving. No moving parts, no noise, no power consumed. Cool video.

  • Besides air blowing into your van from the open hatch... is also the van's exhaust. Be careful.

  • how fast do they cool when the sun goes down i wonder- def some great stuff man- get the world off the grid man!

  • I wonder if if a mirror reflection set up to a brick center piece in a house would work out...(brick chimney dual sided, center of house-

  • well i just have to point somethin out, the shop vac will make heat itself and blow it out so you gotta take that in concideration

  • . The day that I tested this panel it was hazy and a little overcast. the following day my results proved to be far better. At 20F clear skies with a 15 mph wind I was getting as much as a 56F degree increase in temp (71F intake and 127F at the exit port) constant. By 1:30 the interior of my building was 75.4F when I shut it off. I was burning up.. ;0) I have a few ideas for another blower system. I'll post that video when I get finished... Thanks again.

  • Sure, I would be happy too. Give me a day or so to get it put together, thanks again for the great idea.

    D.J.

  • Use the video you did, just click Post a response and select your first video, it will pop up.

  • Great video responses to this video. Check Them Out:-)

  • Hey Dan, I know that you are a busy Cat, but if you got a minute please check this out.

    Thanks

    cGjCzfftMgc

  • FANTASTIC VIDEO Greta Job, do a video response.

  • hi denise i found out something to do with the freznal lens you dont need to cook outside anymore just shine a mirror through your house window and use that reflection to cook i did it it works

  • Have you ever heard of Earth Packed tires used in earthships? I am building a 15' X 8' box out of earth packed sandbags with the interior lined with styrofoam on the walls and sealed completely with thick mil plastic! Inside that I have sand packed tires with black spray painted cans inserted inside the tires to expose the black bottom of the cans then cut pieces of copper flashing and paint them black and puzzle piece the exposed sand to cover it while leaving the cans alone!

  • cont... my sandbag box is stair stepped so it has a 45 degree angle on the front and built a frame enclosing the entire front in plexiglass. The box stands 2 feet high with another 1 foot added riser to capture the heat to transfer to the home via 3 inch insulated PVC. The box gets very hot inside and this design allows the stored heat within the sandfilled tires to slowly seep out heating your home and reducing heat costs dramatically! use a small fan and have 2 pipes 1 for air return!

  • GPS, thanks for getting back to me, I think I'll give it a try. I'll let you know what I come up with.

  • Dan have you or anyone else had any issues with melting the Coroplast inside the sealed solar panel? Seems like the temp would get pretty hot during the summer months. Does anyone know what the critical temp would be? Hate to invest the time and money into something that's gonna melt down.

    Thanks for the great ideas.

  • I think it is 210 to 250.

  • well if u do a biger hole u can use it to put 2 or 3 pieces of card board but the under leyers might not get as much heat

  • Dan the Man! Thanks for all the sweat you put into your ideas. You are doing some great things. I'm going to try a lot of your things - especially this. Again, thanks!

  • Hahahaha lol VOTE FOR DAN! at 15:43 :D :D :D

  • Glad you caught that:-)

    Youtube crunched that part of the video, digital glitch. That is why the sound gets goofy too. By the time I caught it, Youtube had Spotlighted tis video so I did not want to re post it. In the original version it is about 3 seconds long vs. the subliminal commercial flash:-)

  • Check 15.42 :D

  • Dan & Denise...I'm sure enjoying your solar energy projects. This video w/ the corrigated cardboard...reminds me of when I had this house (built in 1920) re-roofed over the old embossed designed metal roof that was leaking. The contractor/friend used a corrigated white fiberglass roofing material called 'ODULINE it lower my un-air conditiond significantly.

    A book named "Low-Cost, Energy Efficient Shelter" was inspirational too.

  • Great Video. I just added to Open Source Energy site. Thanks

  • Acrylic cover,

    Styrofoam back.

    Input to one corner,

    output from the opposite (diagonal) corner.

    So all the air paths are the same length.

  • keep it up thout provocking

  • great idea but, when its 10 degrees out how warm is that cardboard? also, if its outside, wont snow build up on it, blocking it from what little sun us northerners get to begin with. i would like to see this tested in freezing temps, of course its gonna get hot when its 88 degrees out and the sun is beating on it 10 hours a day...still this is a neat idea

  • i was wondering the same, there are some down sides to it. the idea is ingenious.

  • We are due for a cold night here, If it is cold during the day, I will get some temps on the Coroplast. The ideal concept would have an Acrylic cover. Snow can be lessened by angling it directly at the sun. This will help but deep snow, shovel:-)

    A vacuum seal would make the temperatures go way up in cold but the unit would need to be smaller cells and would take some fine workmanship. Thee good thing about this idea, you can shut it off when there is no sun.

  • Another great video thx

  • да же в моделист конструктор было такое ( садовый душ: накачиваем воду в камеру от велосипеда и эту конструкцию на крышу под стекляную теплицу)

  • ну согласитесь отапливать помещение подогретым воздухом с -30 -40С до -20 -30С не так уж эффективно а вот в жаркое сибирское лето запросто.

  • I am going to have to build one of these. I am curious to see if the surface actually heats up enough in this cold Connecticut winter air.

  • Hey got a problem i built it tested it it was 54 outside and was only getting max 36 out of it turns out i made an airconditioner help would be nice thanx

  • ыы пускай они это попробуют в сибири зимой при температуре -40С и 10-20 солнечных днях из 3 месяцев )

  • Simple but nice. You did a great job showing how to make one. Good work. Thanks.

  • Dan do you plan on using some type of corrugated polycarbonate sheet... like green house, signage etc? well this could be the answer to getting it free..."A slip-sheet is a thick corrugated, solid fibre or plastic sheet that sits underneath stacks of shrink wrapped product." So go to a factory/trucking outfit/shipping etc and see if they have any in the dumpster or ask... they throw these things away... later

  • love your videos

  • Try this low tech solution: Get electric heaters at COSTCO--give your money to the local electric utility instead of AL-KAEDA oil. Even if you don't save a dime on your heating bill, you'll drive the cost of gas down, and maybe save a soldier or sailor's life, as oil profits from imported oil feed our enemies.

    Think about it while you're lowering that thermostat. I just cut my oil bill 2/3, and my electric bill hasn't jumped. Paid for the heaters one season.

  • Why does this stop and start so much? Is youtube screwed up? I haven't been able to get anything to play right for days.

  • Youtube has some issues. I have the same problem with some videos. I think it is better today.

  • lol

  • Why not use metal for permanent use with the same concept, which also retain heat much longer and is not COMBUSTIBLE.

    Though this is a good concept short term, longer term could show a house in flames.

    I think some type of metal would be a more safe approach.

  • Dan, that's a great idea. I really enjoy your videos. Thanks!

  • pretty interesting. Homeless survival rating just went up.

  • Hey that's great! A solar heater for summer!

  • Interesting project, fun editing, and great use for those election signs!

  • if youtube has a 10 min limit, how do some videos get extra time?

  • neat, very similar to the passive cooling/heating system set up in my garage cept you use the heat of the sun and i'm using the stable temp of the earth

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  • its a good idea but the energy consumed by the vacuum must be taken into account looks like a net loser all things considered.... maybe a solar powered blower???

  • The vacuum is for testing only. The Coroplast has larger channels a allows for easier air flow. Any 200 watt blower could do the job. A solar blower could work too. This would cut off when the sun goes down or a photo sensor for heavy cloud cover.

  • that's good idea so may be very useful

  • good idea but you can edit this to make it shorter

  • the way u handle that benchsaw was dangerous X_X

  • cardboard paper is melting with rain, snow, and water

  • Great idea

  • Wow creative !

  • fag

  • LOL

  • what a wast of time and wood, cardboard, paint, and so on..... could have all been fire wood!

  • nice welfare heat exchanger, but heating air on a hot day doesnt have a real advantage. 135 F air in your house sounds like fun. If you put water through it, there would be your advantage.

  • interesting stuff sill sub

  • I have an uncle that used this principle to heat a pool. Black painted PVC snaking back and forth on a slope below the pool, encased under safety glass. It had an entrance and an exit to the pool and circulated heated water all thanks to the sun.

  • haha, not until u get the cancer from the uv radiation. dont u think?

  • nice idea...I can also see such a unit or several units encased in safety glass to weather proof with solar fans also installed so that it requires no electric fan

  • Jo-der

  • Good information and Well produced. Keep it up!

  • so how much does your electricity go up pushing air thru it or did I miss something?

  • Instead of trying to "push" the air through with the vacuum, it might work better to "pull" from the opposite side. By doing that, you can completely open the incoming side on the cardboard.

  • i think the higher pressure makes the air inside it more dense, holding more air and increasing contact against the warm surface

  • ¿Como se puede hablar tanto para explicar algo tan sencillo? Macho, no te enrrolles tanto y si quieres ahorrar, ahorra palabras, terminé con dolor de cabeza. La idea es buena pero tu eres un tostón.

  • As always, a great green idea. I will post my own solar furnace soon via video. keep up the good work

  • People in the Air conditioning business will tell You that the outlet needs to be at least twice as large in area than the inlet; so multiple ports out would dramatically improve airflow with much less work on the blower.

    A solar powered blower would make this unit complete.

    Good Job !

  • Random though - I slept on a 'traditional bed' in a preserved village outside Beijing, that had heated coals warming a mattress that rested on a woven mat. It was GREAT. Maybe with a glass cover & insulation, this same thing could be achieved (at a lower temperature).. pre-warmed bed.. really nice.

  • clarification on the bed:

    woven mat & mattress rested on an insulated stone bed frame. 'Coals' were inserted into a brick sized hole below the bed where, I presume, they heated stones that later slowly released the heat. Smoke left through a vent outside.

    Although the host lit something below the bed when we were shown the room, I remember conversation about there the beds needing to be prepared a day/half day in advance (slow stone heating?)

  • "Kang bed-stove" that's what its called.

  • You could improve the efficiency by making the cardboard zig-zag shaped ( /\/\/\ ) instead of simply leaving it flat ( ____ ) as your panel does not align to the sun throughout the day.

  • Cute couple, cute little home made show... Keep up the good work!

  • In cold windy weather, when we would use this, it will need insulation on the back, glass on the front or it will probably make cold air.

    The net energy gain with a grid-connected fan is probably nil if not negative.

    This is a great idea and has inspired me to design a hang-out-the-window-heater using corrugated plastic with a frame made from black ABS pipe. The sides conduct cool room air down to the bottom. The collector plate fits into a slot in the bottom and top frame pieces.

  • "The net energy gain with a grid-connected fan is probably nil if not negative."

    This seemed apparent to me me also. Cool budget diy/tinker idea though. Better as an experiment rather than an application - might have some application in poor countries with suited climates (assuming someone collects corrugated plast