I think you are very smart guy and very sensitive with pollution which is I really admire you and respect you deep from my heart I wish all humanity think like you. 👍
Thank you... Many people have told me about this leaking problem but I have not experienced it yet. If nothing else I think the milk bottle heat storage chamber can be used to experiment with a variety of solar hot air designs.
Your video got me going. I bought aluminum flashing , flat black paint, and some of that plastic board that has channels in it. I left the painted black aluminum lay in the sun , it reached about 131F The plastic material painted black reached 143, 145 F i will update as needed.
The guy in the video looks like a Mad Scientist" but he is NOT stupid , he is very smart and explains things very well with a chart/ drawing. Thx very much sir! Compared to others , they do NOT explain WHY they paint cans black ,or what kind of glues they use, just some POOR examples in their videos. This is the BEST video I ve ever seen , details are covered very well! Good job! Well done!
Sure i Will! I live in Panama Central America. Plenty of sun out here, and taking ideas like yours will help me out greatly to start a sound project of some sort of practical use. I´ll keep you posted.
So where I live the water jugs would freeze overnight! Making it difficult in the morning to bring the house temps up!! However, still love this guy's mind. He inspires me to really think on this one. How about something like nova brick thin and dense that can hold heat for extended period??? Unless tho the extended period was significant it would not be worth the effort. I'm content with the idea of daytime solar heating assistance to my house and night time electric furnace but would love additional options at night. Bravo! Great mind!
Thank you jcanivan, you've solved a problem I've been chewing around in my mind for a little while now! I'm going to take your advice and use plastic bottles to store heat for a greenhouse. Making heat during the day wasn't a problem, storing it for use at night was. ;)
Hoi John. Thank you for doing this test. I also have a solar pop can construction and was already thinking about a simple heat storage like you did. In my case, I need to put the storage inside my home...
Suggestion. Milk jugs are cool, but there are other things more efficient that can be recycled. The best cheap unit to get I know of to exchange air temperature heat to water temperature heat is a car radiator. Used old ones are cheap to free from a car wrecker. Attach that to a 55 gallon fuel drum , with a pipe from the bottom refreshing the water to the radiator and then back to the top of the barrel, with a slow pump also on a solar panel to power it (water pump) and you got a more efficient temperature exchange using recycled materials. The 55 gallon drum water should slowly heat up - just a thought but the efficiency of a car radiator converting air heat energy to water heat energy is phenomenal esp if you have the water cycling through the radiator even if slowly.
onebigkahuna69 Are you sure? I was going to say the captain on CHiP's. I doubt this will work with water where it gets below freezing at night, maybe if you sub the water with anti-freeze.
Thank you Gordon.. Water is the best medium for storing heat. If you arrange tthe bottels right you should be able to extract heat from them by blowing air over them. . Good luck with your project.
A fun experiment John. Pity some of your commentators were not a little smarter. Your work demonstrates 3 things - that there is plenty of scope for getting more out of solar, that re-purposing makes sense, and that (re comments) we teachers failed miserably
John, I can't tell if I love your vids or they just drive me bonkers. When you go to graphics and narrate over them, all I hear is endless health class filmstrips in an overheated, underventilated gymnasium all through junior high. That aside, you do great stuff. I especially enjoy how creative you are with these projects, keep 'em coming.
So how efficient was your system? Are you talking about just a 5 degree rise over ambient over the space an hour or two? You say you have 'stored this heat' in the plastic bottles, but how would you utilize it? How would you transfer this heat in a way that would be useful?
The Jugs of water are used to store heat transferred from hot air. Water is an excellent medium for storing heat BUT you'll need a large surface area to transfer large amounts of heat.
+John Canivan Salt water would be a good idea and being that heat tends to rise the inlet would be better located at the bottom of the heat storage unit.
Right but I can't think of a common container that would meet those requirements....at the price of milk jugs. Pop bottles I believe would be more durable. Much handling and milk jugs leak.
The inlet is in the best place for this setup, the air will be cooled by the water and fall down. Meanwhile, the heat in the collector will rise so you gain the advantage of passive airflow to assist the fan.
Hey John, love your "poor mans sawmill" video!Just an idea, you could make those milk jugs into plastic gasoline, of course you would have to build a mini reactor and fractional distillation plant and save A LOT of milk jugs and type 2 plastic
I saw somewhere that Britain is planning on burnin "hundred of tonnes" of poisonous plastics. This reminded me of a picture where someone filled plastic bottles with shredded plastic and used them like bricks as in-fill in a cob wall.
Natural syphon of heated air might be possible. How will the plastic bottles stand up to the heat? The water will expand from heating, will the bottles expanding and contracting over and over cause the bottles to fail?
Throw away the air heater, install 2 sheets of glass with gap between (double glaze) on bottle chamber , put black dye into water bottles and heat water directly with sunlight , much more efficient than trying to heat with air!
If you let the warmed air enter at the bottom and rise past the water than you might reduce the need the additional electricity for the fan. Insure that the outlet(s) have the same summed cross section area, so to have a good draft. Making the air go down before final exit like the Franklin Stove will make it more efficient. Sand is heavier and takes longer to warm, but releases heat longer. Just Suggestions.
1. Yes, but the thinness of the material reduces the difference significantly. If the water were under pressure, it would have to be thicker and then copper would be the best choice. 2. Why, indeed. Difficult to seal to prevent water loss through evaporation. These are sealed with their original caps. 3. Beats hanging around on the Internet or playing video games. He's a creative guy that makes stuff, this is how he spends his free time. That's cool.
@CTOL1 That could work. Remember a large surface area is needed to exchange a large amount of heat in a short period of time. Air heat exchanges are not very efficient but they might not need to be.
About the addition of Salt yes it will help in keeping the water from getting funky. However unless I am mistaken the addition of a small amount of salt increases its conductivity of heat just as it increases the electrical conductivity :)
Wow!!! Fantastic! You are such a fantastic geek too!...lol. Easy to see you are REALLY into this!!! Love your energy! Okay I would really like to know how hot the water got inside those milk bottles. And I want to know how i can gently release that heat over time so I can keep my chickens snug and warm in a northern environment through our ice cold winters nights! Send me a Personal message if you have a way.
Can you just use a green recycling bin to put water bottles in then set it in the sun and it will heat up ? Try it and see what it do ? And try using smashed metal cans inside of a plastic bin set it in the sun to see if it warm up faster and hotter ? You may add water with the metal cans ?
interesting idea.. Am looking at this differently. Looking to build double wall construction for the exterior walls .. The outside will have all of the insulation.. a thermal break and an intelligent wall membrane on the outer surface of the inner wall. Then exactly as you designed place between the studs just as you did with bottles of water. This will store massive amount of high mass into the building. OK so why? As you were thinking heat exchange. The number of BTU needed to raise the temperature in the house with the high mass is HUGE. So once the house comes to temperature via heating or cooling it will have a tendency to stay at that set temperature. There wont be need to run massive amounts of power sucking energy appliances. This is due to actually well insulating the floor walls and roof structures. Oddly what will be needed is forced air exchange and dehumidification.
John, I have really appreciated your input on many groups, really. This video leaves me puzzled however, as I do not see a point. Collecting heat, to store heat, which goes right back to your heat collector, which goes right back to your heat storage..... etc, etc, etc... I see no way to actually USE the heat you have collected and stored. It is a closed system, which does not help to heat a home, or wash water, or even a chicken coop or dog kennel. When, where, how, does that heat we are collecting and storing actually connect to something we use? Do we manually switch something open at the bottom which leads to a house? Do we wait for a certain temperature before we do so?
It seems to me this is a proof of concept video. For the purpose of taking measurments to see how much heat could be stored etc. the system was intended to be a closed system. For using it on a house, you would want to design the house walls differently. At the end of the video you can catch some of the ideas that are possible as the music plays. Jump to 12:49
I have been looking for a good way to collect the extreme heat generated in my greenhouse that the sun radiates and be able to release it keeping the greenhouse warmer at night. This is a perfect application for this and I think the answer to my search. Thanks, John.
Man I can see it, Did it work well? what was the temp change?How long did the heat that was held last? I like it and would like to try this on my home the help with the big heat bill. I see a nice idea and see how it would work very well. Thank you for this vid!!!
I have a few questions 1. Doesn't aluminum & copper transfer heat (& cold) better than plastic? 2. Why not use soda cans instead of plastic milk cartons? 3. If you were to total up the money you've spent on materials (all of them, including gas for dumpster diving trips), and the energy it took to make the materials, do you still think you have saved a dime and truly made a dent in "saving the planet?" Hope so, it & we need it (saving).
While water is a good way to store heat it is not the best way. It is however, the cheapest by far so in that respect it might be considered acceptable. Water does have a "specific heat" advantage over most other materials and while you can use water's specific heat to store a lot of "sensible heat", you would be better off with a material called a PCM (phase change material), to take advantage of a materials "latent heat". There are many materials that can be used within the more or less practical temperature range of say 65F to 250F (there are many that go much lower and many much higher like common table salt which melts at 1,474°F and can store a lot of heat). Pretty much anything that has a melting/freezing point in the required range will work. Its the process of melting/freezing that can store and subsequently release greater amounts of heat through what is called the "latent heat of fusion". For example paraffin wax could be used (although not in plastic milk bottles), to make a very good heat storage PCM. During the day increasing temperatures would be used to melt the paraffin wax (melting at roughly 120F). The process of melting absorbs and stores quite a bit of heat. When the wax is completely melted the amount of heat stored is approximately 220 kJ/kg (roughly 95 BTUs/lb), which means that 220 kJ/kg will be returned to the environment at night when it cools and freezes at 120°F. There are many natural PCMs that will work such as lard, tallow, coconut oil, cocoa butter, glycerin, etc... They don't have quite the kJ/kg as wax but they're in a very practical temperature range of 65°F to 100°F. In Johns example the 16 half gallon jugs holding about 8 gallons of water at say 120°F, would store only about 4000 BTUs of heat energy where as 8 gallons of melted wax at 120°F would store about 7900 BTUs. Cost is a big driver here since wax is not cheap and in that respect the use of water makes for a much more practical thermal battery. A hybrid of this idea might be to float a large lump of wax in each water jug along with water. It would store more heat but might not be worth the cost.
Yes John, I was speaking more to your audience than to you. I've seen some of your other videos and I suspect you're already familiar with PCM and the latent heat advantage. As for cost and general ease of use, theres no beating plain old water.
@Den0Q If the water keeps freezing in them over a period of time they might leak, but I have be storing water in milk bottles for two years with no loss in weight, I weigh them every few months with a postal scale accuracy .1 oz.
You would get far better results by painting the milk jugs black. Enclose them in your frame, leaving a hole at the bottom to allow the cold air in and one at the top to release the hot air..Skip the 'exchanger' and the fan and all the rest altogether. I don't care how fancy your graph is- the steps in between serve no purpose at all . . Kind of like hiring a butler to tell you that someone is ringing the doorbell.
Joselyn Linnell Yes, black will help the containers to receive as much heat as possible but also, after painting black, the containers will give up all their heat ad quickly as possible. Not a particular problem but this a detail most people do not appreciate.
kayak347 exactly. I stored drinking water in various types of jugs in my kitchen cabinet. They are in the dark. Milk jugs leak every time. Most time I've gotten is a year before they leak. Not to mention in the summer the heat will rise to a point that milk jugs will fail.
And due to the various bacteria that can grow in milk, milk jugs should never be re-used for anything that you will drink. It is impossible to get them totally clean unless you have industrial equipment. Gallon drinking water jugs are safer. Of course, if you are just storing heat energy, milk jugs could work. BUT... If I wanted to heat water for energy storage, I'd build a direct water heating panel and use a large (55 gallon drum or 2 or 5.) storage vessel. A couple dozen half gallon jugs can't store enough energy to be very practical. Using hot air to heat water in 2 liter jugs is going to be grossly inefficient. Run piping through a collector box and let the sun's energy heat the water more directly and much more efficiently. That build isn't much more difficult and will net better results, I think.
Hi, I have a question, I understand that warm air heats the water in the bottle, but how do I do to get my warm bottles in the closet, they heated the house? (Sorry, I'm not American and my English is not very good.) Thank you.
Nice ideal, Will have to do it. It is bad that we are going to the ways of our grandparents who grew up in the depression, They saved everything not hording. We lived on a Farm. In the Barn everything they had they hang it on the walls
Hi Mr. John. I did something very a like with Coke bottles. Does u read still this comments? I would like to share with u my experience. Regards, Carlos Cirera
You can improve this concept even more by making a small Stirling engine to power the fan blades. There are some videos that show how to make a Stirling engine from soup cans.
Yes salt would lower the freezing point of water BUT water has a very high heat storing heat capacity due to the OH stretching bonds and the price is right
Isn't it against thermodynamics to have the heat forced down to the bottom to exit? Maybe I misunderstood, but heat rises. Great video, fantastic design otherwise and great workmanship! Thanks!!
On the heated side the air will rise more than on the stored side which should create a natural convection current. The fan helps it out. Since it's a closed loop and the cooler air on the stored side is denser, it will be constantly pouring out the bottom into the heated side where it expands and rises. It's probably easier to envision the movement from the bottom half.
why not put the fan on the bottom of the water jug section, since hot air rises, but that mean making a tall structure with the heat collector on the bottom and the water jugs above, or a second fan at the bottom near the exit to help pull hot air
You have the idea Linda. BUT it would probably be better to put a fan on top to force the hot air down... Since hot air naturally rises.heat has more value when stored in a low place. This is why radiant floor heating is so effective/
I think you are very smart guy and very sensitive with pollution which is I really admire you and respect you deep from my heart I wish all humanity think like you. 👍
Thank you... Many people have told me about this leaking problem but I have not experienced it yet. If nothing else I think the milk bottle heat storage chamber can be used to experiment with a variety of solar hot air designs.
Your video got me going. I bought aluminum flashing , flat black paint, and some of that plastic board that has channels in it.
I left the painted black aluminum lay in the sun , it reached about 131F The plastic material painted black reached 143, 145 F
i will update as needed.
Thank you John! This reminds me of Doc Brown. Your knowledge is very much needed! Our world is changing fast.
The guy in the video looks like a Mad Scientist" but he is NOT stupid , he is very smart and explains things very well with a chart/ drawing. Thx very much sir! Compared to others , they do NOT explain WHY they paint cans black ,or what kind of glues they use, just some POOR examples in their videos. This is the BEST video I ve ever seen , details are covered very well! Good job! Well done!
I think you are wonderful. I love to see people who upcycle and want to make things from everything
Sure i Will! I live in Panama Central America. Plenty of sun out here, and taking ideas like yours will help me out greatly to start a sound project of some sort of practical use. I´ll keep you posted.
+Obdulio Cerceno Put the sun on your team.
So where I live the water jugs would freeze overnight! Making it difficult in the morning to bring the house temps up!! However, still love this guy's mind. He inspires me to really think on this one. How about something like nova brick thin and dense that can hold heat for extended period??? Unless tho the extended period was significant it would not be worth the effort. I'm content with the idea of daytime solar heating assistance to my house and night time electric furnace but would love additional options at night. Bravo! Great mind!
AWESOME beats at the end of that clip! I want more!
Great stuff John. I am glad I have come across your space. I have a wind turbine design I did 15 or so years ago. video here in my space ;)
Thank you jcanivan, you've solved a problem I've been chewing around in my mind for a little while now! I'm going to take your advice and use plastic bottles to store heat for a greenhouse. Making heat during the day wasn't a problem, storing it for use at night was. ;)
Hoi John. Thank you for doing this test. I also have a solar pop can construction and was already thinking about a simple heat storage like you did. In my case, I need to put the storage inside my home...
Suggestion. Milk jugs are cool, but there are other things more efficient that can be recycled. The best cheap unit to get I know of to exchange air temperature heat to water temperature heat is a car radiator. Used old ones are cheap to free from a car wrecker. Attach that to a 55 gallon fuel drum , with a pipe from the bottom refreshing the water to the radiator and then back to the top of the barrel, with a slow pump also on a solar panel to power it (water pump) and you got a more efficient temperature exchange using recycled materials. The 55 gallon drum water should slowly heat up - just a thought but the efficiency of a car radiator converting air heat energy to water heat energy is phenomenal esp if you have the water cycling through the radiator even if slowly.
I really loved you in the back to the future movies.
onebigkahuna69 Are you sure? I was going to say the captain on CHiP's. I doubt this will work with water where it gets below freezing at night, maybe if you sub the water with anti-freeze.
Great idea, and I am trying this with 10ltr water bottles. Fingers crossed it all works out. Thanks for the good information John.
Thank you Gordon.. Water is the best medium for storing heat. If you arrange tthe bottels right you should be able to extract heat from them by blowing air over them. . Good luck with your project.
Thanks John. If it works as well as yours, I will take some pics and maybe even do a quick video. Regards,
A fun experiment John. Pity some of your commentators were not a little smarter. Your work demonstrates 3 things - that there is plenty of scope for getting more out of solar, that re-purposing makes sense, and that (re comments) we teachers failed miserably
John, I can't tell if I love your vids or they just drive me bonkers. When you go to graphics and narrate over them, all I hear is endless health class filmstrips in an overheated, underventilated gymnasium all through junior high.
That aside, you do great stuff. I especially enjoy how creative you are with these projects, keep 'em coming.
Definately subscribed. Great videos. Keep them coming John.
its great to see new ideas for my project this winter, I can't wait to build one..
So how efficient was your system? Are you talking about just a 5 degree rise over ambient over the space an hour or two? You say you have 'stored this heat' in the plastic bottles, but how would you utilize it? How would you transfer this heat in a way that would be useful?
this video encourage you to go green and save a lot.. I thank you for uploading this.. very helpful..
The Jugs of water are used to store heat transferred from hot air. Water is an excellent medium for storing heat BUT you'll need a large surface area to transfer large amounts of heat.
+John Canivan Salt water would be a good idea and being that heat tends to rise the inlet would be better located at the bottom of the heat storage unit.
Right but I can't think of a common container that would meet those requirements....at the price of milk jugs. Pop bottles I believe would be more durable. Much handling and milk jugs leak.
The inlet is in the best place for this setup, the air will be cooled by the water and fall down. Meanwhile, the heat in the collector will rise so you gain the advantage of passive airflow to assist the fan.
John Canivan
love his humor and explanations!
Hey John, love your "poor mans sawmill" video!Just an idea, you could make those milk jugs into plastic gasoline, of course you would have to build a mini reactor and fractional distillation plant and save A LOT of milk jugs and type 2 plastic
+mrMacGoover save those milk containers
I saw somewhere that Britain is planning on burnin "hundred of tonnes" of poisonous plastics. This reminded me of a picture where someone filled plastic bottles with shredded plastic and used them like bricks as in-fill in a cob wall.
@sandmanmrm Water has a much higher heat capacity than sand,, Also dry sand acts as an insulkator
Interesting idea. I too hate to throw things away - especially plastic. I'm always trying to figure out reuse ways to reduce my footprint.
Very good idea,
Great teacher.
Natural syphon of heated air might be possible. How will the plastic bottles stand up to the heat? The water will expand from heating, will the bottles expanding and contracting over and over cause the bottles to fail?
Throw away the air heater, install 2 sheets of glass with gap between (double glaze) on bottle chamber , put black dye into water bottles and heat water directly with sunlight , much more efficient than trying to heat with air!
Don Graham Thank you Don. Where there is a will there is a way.
Enjoy your videos. Like the way you explain every detail. I subscribed. :)
If you let the warmed air enter at the bottom and rise past the water than you might reduce the need the additional electricity for the fan. Insure that the outlet(s) have the same summed cross section area, so to have a good draft. Making the air go down before final exit like the Franklin Stove will make it more efficient. Sand is heavier and takes longer to warm, but releases heat longer. Just Suggestions.
Love d&b always pleasant workers, like they really like their jobs. Kinda like Christmas all year
Adding salt , common table salt one teaspoon per gallon will yield amazing results.
+Walter Sudymont Great idea Walter
Walter Sudymont Thanks! I'm looking for ways to heat my greenhouse!
1. Yes, but the thinness of the material reduces the difference significantly. If the water were under pressure, it would have to be thicker and then copper would be the best choice.
2. Why, indeed. Difficult to seal to prevent water loss through evaporation. These are sealed with their original caps.
3. Beats hanging around on the Internet or playing video games. He's a creative guy that makes stuff, this is how he spends his free time. That's cool.
How about using (leaks fixed) old car radiators filled with water?
YES!! Thank you!
How much fun is it to top off the milk jugs when needed
@CTOL1 That could work. Remember a large surface area is needed to exchange a large amount of heat in a short period of time. Air heat exchanges are not very efficient but they might not need to be.
About the addition of Salt yes it will help in keeping the water from getting funky. However unless I am mistaken the addition of a small amount of salt increases its conductivity of heat just as it increases the electrical conductivity :)
Wow!!! Fantastic! You are such a fantastic geek too!...lol. Easy to see you are REALLY into this!!! Love your energy! Okay I would really like to know how hot the water got inside those milk bottles. And I want to know how i can gently release that heat over time so I can keep my chickens snug and warm in a northern environment through our ice cold winters nights! Send me a Personal message if you have a way.
Can you just use a green recycling bin to put water bottles in then set it in the sun and it will heat up ? Try it and see what it do ? And try using smashed metal cans inside of a plastic bin set it in the sun to see if it warm up faster and hotter ? You may add water with the metal cans ?
interesting idea.. Am looking at this differently. Looking to build double wall construction for the exterior walls .. The outside will have all of the insulation.. a thermal break and an intelligent wall membrane on the outer surface of the inner wall. Then exactly as you designed place between the studs just as you did with bottles of water. This will store massive amount of high mass into the building. OK so why? As you were thinking heat exchange. The number of BTU needed to raise the temperature in the house with the high mass is HUGE. So once the house comes to temperature via heating or cooling it will have a tendency to stay at that set temperature. There wont be need to run massive amounts of power sucking energy appliances. This is due to actually well insulating the floor walls and roof structures. Oddly what will be needed is forced air exchange and dehumidification.
Did I miss something, Is this a 2 piece system? The milk bottles if outside in the winter will certainly freeze right?
John, I have really appreciated your input on many groups, really. This video leaves me puzzled however, as I do not see a point. Collecting heat, to store heat, which goes right back to your heat collector, which goes right back to your heat storage..... etc, etc, etc... I see no way to actually USE the heat you have collected and stored. It is a closed system, which does not help to heat a home, or wash water, or even a chicken coop or dog kennel. When, where, how, does that heat we are collecting and storing actually connect to something we use? Do we manually switch something open at the bottom which leads to a house? Do we wait for a certain temperature before we do so?
It seems to me this is a proof of concept video. For the purpose of taking measurments to see how much heat could be stored etc. the system was intended to be a closed system. For using it on a house, you would want to design the house walls differently. At the end of the video you can catch some of the ideas that are possible as the music plays. Jump to 12:49
I have been looking for a good way to collect the extreme heat generated in my greenhouse that the sun radiates and be able to release it keeping the greenhouse warmer at night. This is a perfect application for this and I think the answer to my search. Thanks, John.
Thank you Mr Mad Scientist! well done!
Them blue bins or creates from Rite Aid or 7-eleven can it be used for solar heat to heat up a house in the winter ?
Awesome stuff, yes put a little alcohol in each jug to stop freezing. I'm thinking why did you not paint the jugs black to hold more heat?
Man I can see it, Did it work well? what was the temp change?How long did the heat that was held last? I like it and would like to try this on my home the help with the big heat bill. I see a nice idea and see how it would work very well. Thank you for this vid!!!
I recommend that you add salt to that water, you should get another 5 degrees added and you don't have to worry about mold.
I have a few questions 1. Doesn't aluminum & copper transfer heat (& cold) better than plastic? 2. Why not use soda cans instead of plastic milk cartons? 3. If you were to total up the money you've spent on materials (all of them, including gas for dumpster diving trips), and the energy it took to make the materials, do you still think you have saved a dime and truly made a dent in "saving the planet?" Hope so, it & we need it (saving).
Great video.
While water is a good way to store heat it is not the best way. It is however, the cheapest by far so in that respect it might be considered acceptable. Water does have a "specific heat" advantage over most other materials and while you can use water's specific heat to store a lot of "sensible heat", you would be better off with a material called a PCM (phase change material), to take advantage of a materials "latent heat". There are many materials that can be used within the more or less practical temperature range of say 65F to 250F (there are many that go much lower and many much higher like common table salt which melts at 1,474°F and can store a lot of heat). Pretty much anything that has a melting/freezing point in the required range will work. Its the process of melting/freezing that can store and subsequently release greater amounts of heat through what is called the "latent heat of fusion". For example paraffin wax could be used (although not in plastic milk bottles), to make a very good heat storage PCM. During the day increasing temperatures would be used to melt the paraffin wax (melting at roughly 120F). The process of melting absorbs and stores quite a bit of heat. When the wax is completely melted the amount of heat stored is approximately 220 kJ/kg (roughly 95 BTUs/lb), which means that 220 kJ/kg will be returned to the environment at night when it cools and freezes at 120°F. There are many natural PCMs that will work such as lard, tallow, coconut oil, cocoa butter, glycerin, etc... They don't have quite the kJ/kg as wax but they're in a very practical temperature range of 65°F to 100°F. In Johns example the 16 half gallon jugs holding about 8 gallons of water at say 120°F, would store only about 4000 BTUs of heat energy where as 8 gallons of melted wax at 120°F would store about 7900 BTUs. Cost is a big driver here since wax is not cheap and in that respect the use of water makes for a much more practical thermal battery. A hybrid of this idea might be to float a large lump of wax in each water jug along with water. It would store more heat but might not be worth the cost.
+Chuck O Yes PCM use less space to store the same amount of heat but plain water is easier to work with.
Yes John, I was speaking more to your audience than to you. I've seen some of your other videos and I suspect you're already familiar with PCM and the latent heat advantage. As for cost and general ease of use, theres no beating plain old water.
Do you think it would work better if you put sand in your bottles?
WOW i never finished school but this is very educational... thanx
Lmao
Congratulations! Ps: You could replace the water with used car oil. It's better i think. Bye from Italy👏🇮🇹
I don't mean to hate on this video or anything...but what's the purpose of this heater?
What about using concentrated sunlight's heat to mold those plastic jar chips into LEGO bricks for your community or school kids to play with?!
@Den0Q If the water keeps freezing in them over a period of time they might leak, but I have be storing water in milk bottles for two years with no loss in weight, I weigh them every few months with a postal scale accuracy .1 oz.
Thank you. Great video.
thank you i thought it was a good idea, and i will go from here to there with some idea's im working, good job
Thank you James.
Let me know what you come up with.
what keeps them from freezing solid then bursting wide open?
Man you scare the hell out of me. But your idea is just amazing...
@dimesack65
Thank you for your comment. We should be able to make better use of the materials we throw in the dumpster.
You would get far better results by painting the milk jugs black. Enclose them in your frame, leaving a hole at the bottom to allow the cold air in and one at the top to release the hot air..Skip the 'exchanger' and the fan and all the rest altogether. I don't care how fancy your graph is- the steps in between serve no purpose at all . . Kind of like hiring a butler to tell you that someone is ringing the doorbell.
That was great, I'm still laughing.
Joselyn Linnell Yes, black will help the containers to receive as much heat as possible but also, after painting black, the containers will give up all their heat ad quickly as possible.
Not a particular problem but this a detail most people do not appreciate.
Donald Johnson Insanely easily entertained...
John, great idea on the milk jugs; have you considered painting them black for greater heat absorption?
Since the jugs aren't exposed to direct sunlight, painting them black would have little effect on their heat absorption.
A lot of plastic containers these days are photodegradable so they wont last very long before disintagrating in the sun light
kayak347 exactly. I stored drinking water in various types of jugs in my kitchen cabinet. They are in the dark. Milk jugs leak every time. Most time I've gotten is a year before they leak. Not to mention in the summer the heat will rise to a point that milk jugs will fail.
And due to the various bacteria that can grow in milk, milk jugs should never be re-used for anything that you will drink. It is impossible to get them totally clean unless you have industrial equipment. Gallon drinking water jugs are safer. Of course, if you are just storing heat energy, milk jugs could work.
BUT... If I wanted to heat water for energy storage, I'd build a direct water heating panel and use a large (55 gallon drum or 2 or 5.) storage vessel. A couple dozen half gallon jugs can't store enough energy to be very practical. Using hot air to heat water in 2 liter jugs is going to be grossly inefficient. Run piping through a collector box and let the sun's energy heat the water more directly and much more efficiently. That build isn't much more difficult and will net better results, I think.
How does one get this into house or is this put inside of a window?
Hi, I have a question, I understand that warm air heats the water in the bottle, but how do I do to get my warm bottles in the closet, they heated the house?
(Sorry, I'm not American and my English is not very good.) Thank you.
Use a small solar panel to run the fan instead of plugging it into the grid.
nice thinking, you remind me of the Doc from back to the future.
Thank you Psv.
jees yes he looks like the guy flux capacitor :) a bit scarier with the hair
Nice ideal, Will have to do it.
It is bad that we are going to the ways of our grandparents who grew up in the depression, They saved everything not hording. We lived on a Farm. In the Barn everything they had they hang it on the walls
Thank you Milk bottles that hold heat have a special value in winter.
I live in Tampa. Have a few cold snaps down here but that is it.
mad as a box of frogs...i like him!
Maybe if you put some gravel in with the water, it may retain more heat, as it has a higher specific gravity than the water by it's self.
The fan uses a lot of energy. Is this device worth the money you have to pay for the electricity bill?
Since heat rises wouldn't it be more efficient to have the heat exit at the top?
Hi Mr. John. I did something very a like with Coke bottles. Does u read still this comments? I would like to share with u my experience.
Regards,
Carlos Cirera
I like you, Good Job.
Why do you never see these things running in the winter?
What about painting these bottles black and put them directly into the sunlight (in an insulated container with a window on one side)?
got any idea how many BTUs your heater will produce
Q: how long will the water retain heat at night before turning cold?
Would not alcohol like etanol be more efficient than water in heat exchange?
So, like how much salt to a gallon of water well make a difference ?
Good video
What will be the cost of solar heater .my room size 12 ×10×10 foot.
copper and aluminum are the best at retaining heat
@MagickSinger Not sure what you mean
Use a clear front and colored smoke to track you air current (flow) instead of hoping. :)
Would salt be of any benefit?
You can improve this concept even more by making a small Stirling engine to power the fan blades. There are some videos that show how to make a Stirling engine from soup cans.
Thank you. The basic idea is that water is an excelent medium for storing heat.
@prayfortruejustice Thank you so much. I enjoy sharing these ideas.
very nice!
Thank You.There has to be a better use for all these used milk containers.
for what can you use that hot air?
good job
have you considered adding salt to the water?
Yes salt would lower the freezing point of water BUT water has a very high heat storing heat capacity due to the OH stretching bonds and the price is right
I Know for sure that would not work in the winter in the north but may work in the south.
Isn't it against thermodynamics to have the heat forced down to the bottom to exit? Maybe I misunderstood, but heat rises. Great video, fantastic design otherwise and great workmanship! Thanks!!
On the heated side the air will rise more than on the stored side which should create a natural convection current. The fan helps it out. Since it's a closed loop and the cooler air on the stored side is denser, it will be constantly pouring out the bottom into the heated side where it expands and rises. It's probably easier to envision the movement from the bottom half.
I hope this works but my experience with these milk bottles is the start leaking in a few months. Best of luck
why not put the fan on the bottom of the water jug section, since hot air rises, but that mean making a tall structure with the heat collector on the bottom and the water jugs above, or a second fan at the bottom near the exit to help pull hot air
You have the idea Linda. BUT it would probably be better to put a fan on top to force the hot air down... Since hot air naturally rises.heat has more value when stored in a low place. This is why radiant floor heating is so effective/