A magnifying lens. Some dry leaves. The determination to get that first spark. This is one of my clearest childhood memories, and one that many of us will share.
Whether in school, at scouts or at home, using a magnifying lens in an experiment to generate fire is a fairly common activity. But how is this technology useful?
FOR COOKING
Among the first known tools made to harness the power of the Sun are Yangsui burning mirrors, made in Ancient China, around 3,000 years ago.
Like a magnifying lens these concave bronze mirrors reflected and focused the Sun’s rays to a specific point. On a bright sunny day this produced enough heat to start a fire.
In Ancient China a burning mirror was a very useful tool for cooking food. Confucius writes that every son would attach a burning mirror to his belt when he dressed for the day, to later start the family fire.
Chinese man using a Yangsui burning mirror to cook food. Still from an animation that featured in The Sun: Living with Our Star exhibition. Today, burning mirrors have evolved into solar cookers.
Today, burning mirrors have evolved into solar cookers.
They work in a similar way, by concentrating the power of the sun, but instead of using that power to make a fire they cook the food directly. Solar cookers have enormous potential in remote areas of sunny regions, such as parts of India and China, where access to electricity may be limited.
Another benefit is that they do not produce smoke, which is estimated to cause 4 million deaths per year.
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