Solar cooker

a solar cooker is:
A solar oven or solar furnace is a way of harnessing the sun's power to cook food. A metal box forms the simplest solar oven. A set of large mirrors or a large Fresnel lens to focus sunlight to a single point may also be added. On a sunny day a black baking tray or cooking pot can convert thousands of watts of light directly into heat. Temperatures in the oven can reach 400 degrees F (200°C).



Principles of Solar Box Cooker Design

圖片參考：http://solarcooking.org/images/sbc_perspect_cptn.gif
The purpose of this paper is to summarize the basic principles that are used in the design of solar box cookers.
People use solar cookers primarily to cook food and pasteurize water, although additional uses are continually being developed. Numerous factors including access to materials, availability of traditional cooking fuels, climate, food preferences, cultural factors, and technical capabilities, affect people's approach to solar cooking.
With an understanding of basic principles of solar energy and access to simple materials such as cardboard, aluminum foil, and glass, one can build an effective solar cooking device. This paper outlines the basic principles of solar box cooker design and identifies a broad range of potentially useful construction materials.
These principles are presented in general terms so that they are applicable to a wide variety of design problems. Whether the need is to cook food, pasteurize water, or dry fish or grain; the basic principles of solar, heat transfer, and materials apply. We look forward to the application of a wide variety of materials and techniques as people make direct use of the sun's energy.
How to make a solar cooker:
其實solar cooker的做法很多, 有的做到與「鑊型天線」相似, 有的則用多面鏡子圍住煮食用皿等,
但其原理都是用以集中光線到煮食器上, 將光能轉成熱能

因此要達到目標
1)要到陽光充足的地方
2)反射光線的器具要較大, 反射光的能力要好, 也要夠「弧」, 以集中光線
3)吸光的煮食器要用「黑色不反光物」以減少能力損耗
4)反射角計算要準確

太陽爐的原理就係以一個半圓形,
將大陽光集中反射至中心的一點,
在該點就會獲得較高的能量,
從而使中心點加熱!!!!!!
more models on http://solarcooking. org/plans.htm

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