Solar thermal energy:
In the year 1861, the math teacher Augustin Mouchet has patented the first machine capable of generating electricity using sunlight.
Mouchot introduced water in a bucket of iron surrounded by a layer of glass. Solar energy captured between the glass and the bucket warmed the water to evaporation. With this vapor a small steam engine was triggered. Mouchot perfected his machine by having the mirrors, in the form of bowls, in the bucket of iron, in order to concentrate the sun’s rays to increase the amount of steam. Then he mounted the mirrors on two axes in order to follow the sun, thus becoming the first solar tracking device which further increased the heat between the glass and the iron bucket. (Today, mirrors of this type are still used in some facilities in California, USA). However, the electricity generated by the Mouchot’s machine was so minimal, it continued with the procurement of electricity through cheap coal.
With the years the US born engineer Frank Shuman built in Egypt the first installation of solar energy. At 25 kilometers from Cairo installed five enormous mirrors. All the arts had a length of 60 meters. With this standing solar energy radiation water reached at the focal mirrors almost the boiling point. The steam produced this way served to drive the low pressure steam engines of which in turn pumped the water from the Nile to the farmers’ fields.
This Frank Shuman’s installation of solar energy was the predecessor of the current solar installations in California, which only differ from the first because they generate electricity directly. These facilities were destroyed in Egypt during the First World War and after the war were not rebuilt. Interest in solar energy was declining due to low oil prices and that did not change until the arrival of the big oil crisis. Then we returned to invest in solar systems that still used to today.
Photo-voltaic solar energy:
As early as 1839, the French physicist Alexandre Edmond Becquerel discovered that there was an electric flow between two electrodes bathed in an acid when subjected one of them to a light source. In 1873, the British engineer Willoughby Smith discovered that chemical selenium showed a change in its electrical resistance when subjected to a light source. With the solar cell based on selenium however there was only energy-efficient conversion of 1%.
80 years later, Bell Telephone Company Labor employees found that silicon cells had ana energy efficiency five times greater than the cells of selenium. These new cells were used primarily on a telephone relay station. However, due to high costs investing in such cells has stopped.
Thanks to the aerospace activities the silicon cell is not entirely disappeared from the earth because it meant the most effective and easy source of energy in space where the sun never goes away. The first satellite with silicon solar cells was put into orbit in 1958. With the second big oil crisis, photovoltaic energy finally started its road to victory, just as had happened to thermal energy before. In the mid-eighties, the world’s photovoltaic power increased to 25 megawatts and two years ago 125 Megawatts were produce globally.
