The energy
of the light is part of your existence. Without it life wouldn’t have been able
to grow, and if it suddenly ended, life would disappear.
The
relationship between the man and the Sun has always been filled with mystery and
confusion. Since the men started to consider the sun a God, the explanations
about the light and energy we get from it were variants, but we have always
known how to take advantage of its effects.
The first
farmers discovered, many thousand years ago, the relationship that exists
between the hours of sunlight exposure and the speed of growth of some
vegetables, but until the scientists clarified the process of Photosynthesis,
said relationship was difficult to explain.
Some
villages in the ancient times came to develop mirrors and lens capable to
concentrate the light, but besides on rare occasions, people only took
advantage of some of the reflective and refractive properties of the light,
without knowing how to explain the energetic properties.
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| Source: inhabitat.com |
In places
with high sun exposure times and clean atmosphere, is possible to obtain
part of the domestic electricity from the Sun. Through big panels, provided
with a high number of photovoltaic cells, its possible to transform the solar
energy into electricity to warm the house, make run the appliances, get hot
water and all those things we usually get thanks to the energy from the
electric companies. All of this thanks to a clean and economic system.
The
sunlight going mainstream
The human
beings have learnt to use the sun light better. Little and big experiments have
been developed to make our lives more comfortable. Greenhouses use the sunlight
to maintain its elevated inner temperature; in cold weather places, the homes
have big windows to use better the light and heat from the sun. There are
experimental electric centrals that transform the energy through photovoltaic
cells.
The
invention of the artificial light
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| source: littlerockfamilyhousing.com |
So far we
have seen examples of how the solar energy can be transformed into other forms
of energy. However, human beings also have learnt to produce light from other
energetic sources.
Our
ancestors discovered that anything that burns produces certain amount of light,
but it took a long time to find materials that could burn slow enough and
produce significant amount of light. The torches, the candles and candiles were
the only acceptable result produced after thousand of years, until in the XIX
century some experiments were developed to use the gas and petroleum as
lighting systems.
At the end
of that century a really effective system of artificial illumination was found:
the light bulbs that could produce light from electricity. Inside there was a
metal filament; when electricity flows, the filament heats ‘til incandescence
and produces light. For the filament to not burn, Oxygen must be removed from
the inside of the bulb. Many electric lamps have been developed; some don’t
have filaments, but gases capable to emit light.
