What do we mean by wind energy?
Before the 20th century the renewable energy sources had a crucial role in the economy. People used it in every domain of life. Wind energy is the useful energy that we gain when we capture the wind. With its power men could transport bulk goods on the sea, process crops, mill, and later drain extended areas. The heyday of wind energy usage can be put between the 17th to 18th centuries. Unfortunately from the beginning of the 19th century due to the industrial revolution, and the appearance of the steam-engine, the usage and improvement of windmills dropped significantly. The great energy crisis after the Second World War represented the turning point, but the actual breakthrough is considered to be the 1970s oil crisis. Environmental protection also began to materialize round that time. Today the usage of wind energy started to gain more and more ground. As it is a global phenomenon, the energy of wind is the world’s fastest growing energy source, and most important, its use does not involve any emission of polluting substances. Through the development of technology, the present wind energy capacity outranges every forecast.
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How did they use it in the past?
Sails
In ancient times human have already used equipments whit which they could turn the power of wind to their favor. The most well-known example to this is the sail.
Tens of thousands of years ago people built boats out of wood, reed and faggots. They stretched animal lather on a wooden frame and that way they could travel on lakes and rivers. Even the ancient Egyptians used sails to ease the work of the oarsmen. The sail was made of papyrus plant or other woven filaments and was stretched on a mast. Its lower corners were fastened, and ropes led to both yard-arms. This way they were able to sail in a bit different ankle from the direction of the wind.
Later, when men learned how to use this power, they put out on seas and oceans. To these long journeys the most suitable rigging was found to be the cross-jack.
What do we mean by cross-jack rigging?
In the case of crusader rigging, the sails are in transversal position, perpendicular to the ship’s longitudinal axis. With treir help the the power of the wind can be multiplied significantly.
3000 years BC. men have already transported the goods on sea. The rigging of the cross-jack rigged ship was directed so as to sail before the wind. The disadvantages of this kind of rigging were that the propelling force of the wind couldn’t be controlled and if the direction of the wind suddenly changed, the ship had to switch over to “manual mode”.
Because sailing before the wind didn’t turn out to be the best way of traveling, people began to search for new methods to find out how they could sail in a different ankle with the direction of the wind. The Arabian people came up with the solution: they turned their sail lengthwise with the ship, in this way they were, in some degree, facing the air-flow. The wind bellied the sails out, and streaming along them, it caused such a force that’s one component moved the ship forward. This discovery led to the appearance of the hosszanti rigging. This kind of rigging helped the maneuvering in a great way. The sails were placed along the centerline of the ship. This method was first used in the regions of the Mediterranean sea and the Indian ocean. A range of different sail shapes appeared: for sailing in the eye of the wind, the triangular sail, while for sailing down the wind the quadrangular sail was found to be better. There were some ships using both types of rigging. The triangular Latin sail appeared on the 5th century’s Polynesian sailing canoes, and later, in the 9th to 13th centuries, spread on the Mediterranean sea. |
