Dear friend,
I am simply overwhelmed by the praise and affection showered on me by over 300 people who have cared to write to me about my small invention Snowbreeze. I wish I really deserved it. I can only try to live upto it.
I have read every one of the letters emailed to me In view of pressing telephone calls from across the country, to reduce the waiting period that would be involved if, with all my limitations, I were to reply to each letter individually, I have decided to answer collectively all the main points raised in these letters.
The Essence of
Snowbreeze 4
The central fact to remember about Snowbreeze-4 in its present form is that it is heavily ice dependent and is most suited for offices, groups or bulk users who can obtain ice at the wholesale rate or supplement their supply with ice from the refrigerator. Mass ice delivery systems will have to be developed for this green technology to prosper for the benefit of the people.
Simultaneously chilled water cooling systems (described in the section on “Automated Models” on our website www.greenairconditioner.org) will have to be designed for divergent needs.
At the same time for moderate cooling, and as a safeguard against power breakdowns, it is a panacea against heat for many a middle class home.
1. Availability of Snowbreeze
I am trying to find a suitable manufacturer for Snowbreeze 4. Meanwhile, kindly note I am only the inventor not a manufacturer of this cooling device. If I were the latter I would be a millionaire today with all these orders in my hands for single and multiple units.
I have already sent to some friends a step by step guide on “How to Make your own Snowbreeze. For the rest I am including it in this note. (If you have not received it please ask for a copy).
If, however, you would prefer to have it made for you, my advice is that you wait till a proper manufacturer is found.
A gentleman in
2. How To Make Your Own
SNOWBREEZE 4
By now, after a few more very useful experiments in real summer conditions, I am now fully ready with an answer to what you need to make your own Snowbreeze-4 immediately:
A little courage or willingness to risk a small amount of money if the product fails to come upto your expectations. I can assure you it will still be useful and pay back in kind more than what you spend on it.
Ask any desert cooler maker to give you a standard desert cooler of the following size: Body 20” square and 26” high. The lower 6” of it will be the tank. He should be told this in advance.
(In places where desert coolers are not available a tin box of the same size will do. For the grass pads substitute two 4”x1” cuts on top of two sides of the box. Each cut should be covered by two layers of wire guaze)
The vendor should provide an easily removable metal sheet to cover the tank. The sheet should have four holes for plastic pipes about four inches away from the border. It will help if the sheet is cut in the middle in two overlapping halves to facilitate handling of ice and tullu pump.
(a) The desert cooler maker should also fix three sliding panels of the same tin opposite the three grass pads with a gap of 0.25 inches between pad and panel. The gap should be sealed on three sides and open only at the top for air to enter.
(a) He should also provide a leak proof tap near the bottom of the unit to drain out used water.
(b) He should fix a detachable plastic grill on the unit. This can also be done by the electrician who fixes the fan.
A plastic tub, five inches high and with a diameter of between 15” and 16”, but not more, to be placed in the tank.
An aluminium pan, about 4.5” high and wide enough to hold five or more kilograms of ice or water.
A powerful tullu pump that can propel two to three streams of water in the copper coils. It has to be twice as powerful as that normally used in desert coolers.
(a) Two copper coils 3/8” (1cm) in diameter and each fifty feet long (the standard coil length available in the market).
(b) The copper merchant should be asked to get the coils wound further to form two concentric spirals, one with an inner diameter of 9” and the other with an inner diameter of 10” so that one fits into the other to form the cooling mesh. Copper merchants readily provide this service themselves or through some neighbouring shop.
An exhaust fan. I am using a 12” exhaust fan with a speed regulator for a dual purpose unit. If you want to use your unit only as an AC, an eight inch exhaust fan should be enough. But remember:
You must not use a 12” fan without a speed regulator. Otherwise it will eat up your ice in no no time. Ideally, you should have a speed regulator with the 8” fan too to be able to draw only as much air as can be cooled effectively by the copper coils. This will reduce wastage of ice.
The cooler maker should be told in advance about the fan size so that he can make adequate provision for it.
An aluminium sheet 1.5’x6’
Two meters plastic pipe with a small Mseal packet
It needs to be emphasized here that one needs no skilled help to acquire the above listed items which are all readily available in the market. Any intelligent peon or messenger can get them for you without your stirring out of the house.
All that you need to do now to get your Snowbreeze going is to fix the copper coil mesh behind the fan in a particular manner so that no air enters the room from it except through the copper mesh and it is insulated from the heat of the motor of the fan. Here you may take the help of an ordinary electrician, carpenter or mechanic, whoever you happen to be familiar with.
The procedure for doing this is as follows:
Wrap the aluminium sheet around the copper coil tangle in such a manner that about three inches of it remains open for being tightly nailed or fixed by wire or adhesive to the body of the cooler around the fan. This should secure the fan from drawing any air directly from the air chamber. The coil mesh should touch the frame of the fan and completely envelop the motor of the fan but must not put its weight upon it. The mesh can be suspended by wires from the ceiling of the cooler body. It should also be at least one inch above the metal sheet covering the tank so that the sheet can be moved about freely.
The remaining part of the aluminium sheet should be used to form an open ended spool shaped cylindrical wrapper for the inside of the coil mesh so that it completely covers the motor of the fan and is fastened to its frame. The air entering the hollow glass shaped space behind the motor of the fan is thus separated by it from the copper coil.
Your own role requiring some skilful handling is thus confined to only fixing of the coil mesh behind the fan.
The rest is easy. Place the plastic tub inside the tank. The 4.5” high aluminium pan should be put inside it. It will take about four to five kg ice. The rest of the ice, chilled water the tullu pump can be placed in the remaining space in the tub. The copper coils can be joined to the tullu pump by plastic pipes so that chilled water from the tank circulates in the copper coils and falls back in the tank. You should observe the two returning streams to ensure proper circulation before starting the unit. Finally, place the metal sheet over the tub to insulate the water from the air chamber above.
Caution:
To start the unit you need to add some water (about five litres) for running the tullu pump. Never use normal tap water. Use only chilled water from the fridge for this.
Make sure the coil you put in is kink free. Bend only through pipe bender (see website) or let the copper merchant do it for you.
Thus, you will see that it is a simple job to assemble a small Snowbreeze module. You should remember it is a layman’s contraption born of sheer necessity and any other layman can make it just as easily as he did. This module can then be modified by different people to meet their specific needs.
You can always send me an email for help if you come up against a problem while making a unit. I shall promptly answer it.
An update
1. If you want your unit to run for a longer stretch at a time you may consider having a ten-inch deep tank for it instead of six inches deep. The tub capacity can be enhanced by putting a lining of aluminium sheet or fibre glass inside it and extending it to the desired height.
2. As far as possible ice must be kept in a sealed box of aluminium or stainless steel in the plastic tub inside the tank. The tank should be covered with a metal sheet.
3. Make sure that all air entering the room from Snowbreeze comes only through the copper coils. This means that the area behind and around the motor of the fan must be sealed off from the coils completely. Also the area above the coils must be sealed off upto the body of the unit around the fan.
4. The 9” fan should be fitted with a regulator and should not be run at high speed.
If you start making a unit along the guidelines given on the blog and website www.greenairconditioner.org you can email me for help whenever you face any hurdle.
Best wishes
M.B. Lal
3. Humidity control
Snowbreeze certainly condenses a lot of air and the condensed water keeps falling in the water tank below through a crevice in the metal sheet covering the tank. Beyond saying that it has kept my room very pleasant and relatively dry throughout the monsoon season in
4. Ice Consumption
Normally, I would go by the thumb rule of 2.5 kilograms of ice per four per 100 square foot space. It could be more during peak heat hours and less at night. Also roof top rooms and similar hot sites may need a higher average consumption. It also depends on the size of the machine and fan speed.
5. Large places like institutions or big homes with multiple units
It is the most ideal choice for groups and multiple unit users, institutions, small hospitals, halls and the like who can buy ice in bulk. Factories deliver ice to vendors and bulk users at about one rupee per kilogram whereas the vendor sells it for Rs.2.5 to Rs.3 per kg and often cheats on weight. It can be rolled from room to room or bed to bed in hospitals and dorms.
6. Degree of cooling : MILD
You must remember it is not a 1.5 ton airconditioner that consumes ten to twenty times the power that Snowbreeze does (in making ice and running the fan). It should give you relief by five to seven degrees centigrade which makes all the difference to most middle class people. Normally when the city reports a temperature of 42 to 45 in the open, air temperature in the room without a cooling device is seldom above 35oC. Snobwreeze brings it down to between 28oC and 30oC.
It can give you a higher drop in temperature if you are prepared to spend more on ice. Further, believe it or not, in
7. Using only as AC
One major advantage of the letters I have received is the revelation that everybody wants Snowbreeze only as an AC. Very few seem to be interested in it as a dual purpose facility that can be used both as a desert cooler and AC. This preference opens up new options in making improved single purpose designs. For instance, we can now use a smaller fan and a more compact arrangement of the copper coils. Details can be discussed later.
8. Automated Snowbreeze 4
Several friends have expressed a preference for an automated model. My experience of the past three years shows that to be really useful it should be automated so that one does not have to worry about putting ice in it every six hours or so. For this it has to be attached to a chilling machine or a refrigerator and detatched when taken to another room. This process is described in detail in the section on automated models in the Snowbreeze website. For a regular manufacturer it should be possible attach a chilling machine at an additional cost of Rs.5000. (The condenser which generates heat has to be kept outside the room). For additional cooling during hours of peak heat some ice can be added from the fridge.
9. Converting Old coolers into ACs
Some friends wish to convert their old coolers into ACs. In this two factors are important, namely, the size of the body and the power of the fan in terms of watts. A big cooler can be converted to cover a large area that would justify higher ice consumption. You can put a regulator to slow down the fan and thus use less ice to suit a smaller area but it will still consume more power and may not work on an inverter during power breakdowns. Finally, it has to conform to the norms described in the “How To Make” note.
10. Cost
Ideally, to cover room space upto 150 sq ft., a body 20” square and 26” high (including a six-inch high water tank) should be enough. Together with a metal sheet and three tin panels to be set parallel to the grass pads, it should cost between Rs.1500 and Rs.1800. An 8” fan and a tullu pump would be worth Rs.1000/- Two copper coils, each of 50 feet length and 0.4” or one centimeter diameter should cost Rs.2000/. You can buy a grill for Rs.200/- making a total of around Rs.5000/- in materials.
11. Update, improvements and tips for making Snowbreeze 4 at home
The advent of summer made us realize that this model was consuming more ice than the others we made over the past three years. To bring it line with the rest without losing its higher efficiency we have made the following four changes:
1. Put a plastic tub of 15” diameter and 5” high inside the water tank.
2. Put a regulator on the 12” fan to bring down its speed so that it draws just the amount of air that the coils can cool.
3. Put three wooden sliding panels opposite the grass pads with a gap of 0.25” inch between the two, sealed on the sides and open only at the top to make sure that surplus air does not indirectly transfer its heat to the coils and thence to the ice.
I am happy to report that the experiment was a complete success. Further,
I have developed a technique (which I have yet to put to test)
whereby you can economise on copper coils. If you insert a ring of aluminium pipes (half-inch apart and each of half-inch diameter) between and on both sides of the copper coils (like a ring of pencils tied in a wire) they act as fins, maximize the heat exchange with the minimum use of copper. You too can experiment with this technique.
Finally, I invite those of you who have expressed their keen interest in environmental problems to join in improving and perfecting Snowbreeze 4, by setting up trial units at your homes and improving upon this nasecut technology in your own way. For this you can also interact with likeminded friends on my blog www.snowbreezeac.blogspot.com
The following information may appear to be a repetition to some of you.
IMPORTANT WARNING:
Snowbreeze 4 is not everybody’s cup of tea. At present it is an experiment.
For the present we have succeeded in making highly successful trial models. But these are only trials. Snowbreeze 4 is far from being a commercial product yet.
At the moment I cannot give you precise estimates of the input-output ratio in terms of the quantity of ice needed to achieve a certain expected degree of cooling in different locations and situations.
You are welcome to join this experiment by setting up a unit at your house, at your own risk about its eventual functionality, since it is so cheap to make and run.
It may eminently suit some persons like me and may not suit others at all. So please read this note carefully before taking the plunge.
It is designed mainly for:
It is the most ideal choice for groups and multiple unit users, institutions, small hospitals, halls and the like who can buy ice in bulk. Factories deliver ice to vendors and bulk users at about one rupee per kilogram whereas the vendor sells it for Rs.2.5 to Rs.3 per kg and often cheats on weight.
All classes of people needing relief from power breakdowns.
Only the middle class people like me for regular use, who are not too particular about enjoying the same chill in peak summer as from a 1.5 ton wall AC, do not need it round the clock and can take the trouble of producing about 8 to 10 kg ice and equal quantity of chilled water in their own refrigerators.
For those among all classes who have unlimited access to ice and chilled water. They can enjoy nearly the same comfort from it as from a wall AC. Also good for middle class hospitals, nursing homes, hotels, restaurants and the like.
12. Dual purpose use
Snowbreeze 4 can be freely used both as an air conditioner or a desert cooler by merely rolling it in and out of a window and pressing the right button.
The water tank is common to both systems. When used as an AC (inside the window) a tullu pump circulates chilled water in the copper coil while the grass is kept dry. When used as a desert cooler (outside the window) another tullu pump pours normal water from the same tank on the grass. The tank is separated from the air chamber by a thick metal sheet. The change over to AC merely means rolling it a few inches inside the room on the same angle iron frame and shutting the window behind it.
13. Genesis
A 1.5 ton wall air conditioner consumes two units of power in an hour which is enough to run Snowbreeze for several hours. One unit of electricity can produce 20 kilograms of ice in an ice-factory and 10 to 12 kilograms in the family refrigerator.
The genesis of Snowbreeze and its philosophy and economics has been explained by me on pages 5 to 8, in my book “Make your own Air conditioner” whose text I have put on my other website, www.gandhionline.org.
One can only hope that when use of ice and chilled water becomes more popular –– out of sheer necessity and due to growing magnitude of the problem –– home delivered ice supplies at reasonable rates will become common practice. Ice factories deliver ice at Rs 1 per kilo to vendors.
14. Variables:
Duration of use. (How many hours per day?)
Size and location of room. Roof top rooms will need more cooling.
Total availability of ice and chilled water @ in the family fridge (b) delivered by vendor.
Quality of cooling wanted (mild or high)
To be used mostly in day or at night? During the night ice consumption is low and in early morning hours even lower.
Roughly speaking, for a small unit covering a room of about 150 sq feet it will be 3.5 kg per hour from 10 am to 10 pm and 2.5 kg per hour from 10 pm to 10 am. It can be less if you are satisfied with mild cooling. A bigger unit will consume more ice.
Whether needed only as air-conditioner or as desert cooler too, in which case additional variables are
size of window
If to be moved from room to room a trolley will be needed, or else a fixed frame in the window will do.
15. Shipping It to other cities
I have ‘orders’ from friends in all parts of the country for over a hundred Snowbreeze-4 units to be shipped to them. This is plainly impossible. A unit sent for research purposes two years ago to BITS (Pilani), Goa Campus, packed in a wooden crate and heavily cushioned with thermocol, in a DTDC container, reached there thoroughly shaken. It had to be repaired by the institute’s engineers. Snowbreeze-4 is still not a factory made commercial product. It is a hand-made improvisation, okay for a trial run at Rs.5000/- but not worth spending twice that amount or more on it and then repenting.
Best wishes
M.B. Lal
i thanks to for introducing this type of product very nice product
ReplyDeleteQaseem Khan:Sir i m highly inspired by this endeavour of yours. I am a student of mechanical engineering and i wish to make a snowbreeze of ma own and want to tkae green air condition as my final year project . I just wanted to have a look of snawbreeze . Can you help me in any way . Taht would be very kind of you . I will wait for your reply. Ma email id is qas.undertrial@gmail.com and ma contact no. is 9760524708
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