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Budget – No set budget, however the more materials that can be salvaged or easily acquired by most people, the better. | Budget – No set budget, however the more materials that can be salvaged or easily acquired by most people, the better. | ||
Durability – | Durability – The project must be able to withstand periodic exposure to the elements, especially sun, over the course or years. Also, sitting in the chair must not damage the reflectors. | ||
Portability - The device should be lightweight so that one person could move it without toil, and compact enough to be towed via bike trailer. [[Rattan]], the fiber that many Papasan chairs are made from, is reasonably light weight- making reflector material the key issue in terms of weight. | Portability - The device should be lightweight so that one person could move it without toil, and compact enough to be towed via bike trailer. [[Rattan]], the fiber that many Papasan chairs are made from, is reasonably light weight- making reflector material the key issue in terms of weight. | ||
Design - Should incorporate new improvements or previously not thought of innovations to the solar cooker plan. | Design - Should incorporate new improvements or previously not thought of innovations to the solar cooker plan. Should be stable in mild wind. | ||
Synergy/Integration - Should be a multi functional device, capable of easily purifying water as well as cooking food, igniting paper or grass when needed, and still be able to fit easily into an everyday household setting. | Synergy/Integration - Should be a multi functional device, capable of easily purifying water as well as cooking food, igniting paper or grass when needed, and still be able to fit easily into an everyday household setting. | ||
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==Design== | ==Design== | ||
A solar cooker is used to concentrate sunlight onto a pot or dish for efficient, fuel-free cooking. There are several shapes a solar cooker can take on, from box-like to parabolic, spherical, funnels and plane mirrors. Each form has different pros and cons in terms of construction, durability, materials, performance, etc. | |||
A solar cooker is used to concentrate sunlight onto a pot or dish for efficient, fuel-free cooking. There are several shapes a solar cooker can take on, from box-like to parabolic, spherical, funnels and plane mirrors. Each form has different pros and cons in terms of construction, durability, materials, performance, etc. | In math, a parabola is a conic section with the graph (y=x²) on a Cartesian plane. If that 2-D image were to be "spun" around the origin in the 3rd dimension, the resulting shape would be a paraboloid, the shape used by this cooker. Both parabolas and paraboloids have the effect of concentrating energy waves to a point known as the focus. There are numerous examples of parabolas in the natural world. | ||
[http://en.wikipedia.org/wiki/Parabola#Parabolas_in_the_physical_world] | |||
Parabolic cookers seem to be heavier, more expensive and require constant tracking in relation to the sun, as compared to the other types of solar cookers. However, they have the advantage of being able to reach higher temperatures due to the precise focus created. | |||
The parabola frame can be constructed from almost anything; it can be cast from a mold, fabricated, or utilize a pre-existing paraboloid. The frame can also be the reflective surface itself, in the case of sheet metal parabolas. It seems to me, and to Bart who has much experience, that a used Papasan Chair would provide a stable, sturdy and possibly deep focused frame without having to purchase new materials. It would also be the easiest form of fabrication. This method is not available in all areas, but there are probably enough old satellite dishes to provide cookers for a significant part of the population. The reflective surface itself can be Mylar, glass, or steel, aluminum, each varying in weight, price and availability used. XXXXX CUT DOWN | |||
Table for reflector materials | Table for reflector materials | ||
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Bike Rim Suspension for Frying Pan - Picture | Bike Rim Suspension for Frying Pan - Picture | ||
Ideally- [[Image:HotPot-cooking-vessel.jpg|frame|The HotPot cooking vessel consists of a dark pot suspended inside a clear pot with a lid]] | |||
==Safety== | ==Safety== | ||
Revision as of 03:34, 29 April 2008
Background
The word "Synergy" comes from the Greek words for “to work together”. This project combines the existing parabolic shape and comfortable sitting cushion of the Papasan chair with the natural-source energy utilization of the solar cooker. My hope was that, in the spirit of synergy, the whole would be greater than the sum of the parts and that people may find the idea of owning a solar cooker more practical if they can also sit and read a book in it when its not in use. Compared to the traditional mono-functional Parabolic Solar Cooker, this project serves as a chair when not in use, which saves space and is less of a fire hazard than the traditional Parabolic Solar Cooker. The opportunity to work with Bart Orlando means that this project can benefit from innovative design that comes from years of experience. It is built mostly from salvaged materials as to not contribute to consumption.
Literature Review
http://solarcooking.wikia.com/wiki/Compendium_of_solar_cooker_designs
• http://solarcooking.org/ http://www.fsec.ucf.edu/en/research/solarthermal/solar_cooker/documents/reflectivematerialsreport.pdf
Criteria
These are the criteria that the project was designed to meet.
Time – Must be able to be designed and constructed within the timeframe of one college semester, or about 4 months of part time labor.
Budget – No set budget, however the more materials that can be salvaged or easily acquired by most people, the better.
Durability – The project must be able to withstand periodic exposure to the elements, especially sun, over the course or years. Also, sitting in the chair must not damage the reflectors.
Portability - The device should be lightweight so that one person could move it without toil, and compact enough to be towed via bike trailer. Rattan, the fiber that many Papasan chairs are made from, is reasonably light weight- making reflector material the key issue in terms of weight.
Design - Should incorporate new improvements or previously not thought of innovations to the solar cooker plan. Should be stable in mild wind.
Synergy/Integration - Should be a multi functional device, capable of easily purifying water as well as cooking food, igniting paper or grass when needed, and still be able to fit easily into an everyday household setting.
Level of embedded energy - Materials should be found or salvaged so that it can be shown that this can be built without industrial equipment.
Ease of use - If multiple parts are to be used, then they should be safe, employ intuitive design, and not require the use of tools for operation.
Design
A solar cooker is used to concentrate sunlight onto a pot or dish for efficient, fuel-free cooking. There are several shapes a solar cooker can take on, from box-like to parabolic, spherical, funnels and plane mirrors. Each form has different pros and cons in terms of construction, durability, materials, performance, etc. In math, a parabola is a conic section with the graph (y=x²) on a Cartesian plane. If that 2-D image were to be "spun" around the origin in the 3rd dimension, the resulting shape would be a paraboloid, the shape used by this cooker. Both parabolas and paraboloids have the effect of concentrating energy waves to a point known as the focus. There are numerous examples of parabolas in the natural world. [1] Parabolic cookers seem to be heavier, more expensive and require constant tracking in relation to the sun, as compared to the other types of solar cookers. However, they have the advantage of being able to reach higher temperatures due to the precise focus created. The parabola frame can be constructed from almost anything; it can be cast from a mold, fabricated, or utilize a pre-existing paraboloid. The frame can also be the reflective surface itself, in the case of sheet metal parabolas. It seems to me, and to Bart who has much experience, that a used Papasan Chair would provide a stable, sturdy and possibly deep focused frame without having to purchase new materials. It would also be the easiest form of fabrication. This method is not available in all areas, but there are probably enough old satellite dishes to provide cookers for a significant part of the population. The reflective surface itself can be Mylar, glass, or steel, aluminum, each varying in weight, price and availability used. XXXXX CUT DOWN
Table for reflector materials
Implementation
Always over-build
Tied in back
Bike Rim Suspension for Frying Pan - Picture
Ideally-
Safety
- As with any type of concentrated energy this has the potential to be dangerous and must be respected. Solar cookers can easily reach temperatures above 450 degrees Fahrenheit. Care must be taken around small children and animals, especially when hot food or liquid is suspended from a tripod.
- Solar Cookers have the potential to start fires if left unattended in the sun. This is easily avoidable with this project, just put the cushion on when the Cooker is not in use.
- Be SURE to use SUNGLASSES with UV protection when cooking/testing/adjusting your cooker! Concentrated sunlight is even more damaging to the eyes than the regular kind... And if you are wearing cheap sunglasses that only protect against visible light, you will be more comfortable than usual when staring at concentrated UltraViolet radiation that you can't see. This radiation is even more damaging to the eyes than visible light. UV protection!!
Cost
Papasan Chair - Donated
4 X 8 Anodized Aluminum Sheet - Donated*
Ball of Hemp Twine - $3.50
Pliers - borrowed
3 Bamboo poles sized 8' by 1 - mad river garden supply - $3
9' Length of chain - ace hardware - $9.00
1" long 5/16th bolt/nut - donated
1 bicycle inner tube with puncture - donated
1 small container Citra-Solv natural de-greaser - $3
1 gallon size tin can
- Notes on reflector
From working with Bart Orlando, I had the opportunity to
Discussion
The Bamboo + bike tube = awesome stand
chair- perfect parabola? not quite. close enough to cook with. though focus is a little wide.
External Links
http://solarcooking.wikia.com/wiki/Compendium_of_solar_cooker_designs An Excellent Overv
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