Dr Luria, an expert on solar energy, offered to give a talk at my school. When my teacher announced that Dr Luria was coming, everyone complained. They asked why they had to miss the sports lesson to hear Dr Luria talk! Well, I’m happy to report that Dr Luria was actually very interesting!

Dr Luria explained the basic methods of using the sun’s energy. Firstly, there are photovoltaic cells (called PV cells for short). PV cells form solar panels, and many buildings are built with solar panels on the roof. Solar panels change sunlight directly into electricity, which is used to heat water in swimming pools, and a single PV cell can charge calculators and watches. Secondly, there are solar power plants which use the sun’s heat to produce steam from water. The steam is then used to power electric generators.

Dr Luria said that the idea of using the sun’s energy wasn’t new at all. He reminded us that people had used the sun’s energy for centuries to dry clothes and make fires. He also mentioned an explorer called John Herschel. He said that Herschel had used a “solar collector” to cook his food on an expedition to Africa in 1830. Luria added that plants had used solar power for millions of years as they converted sunlight into the energy that they needed to grow. This, of course, is the process of photosynthesis.

Probably the most amazing thing that Dr Luria saint was that the amount of light that hit the Earth’s surface in one minute could provide the whole world’s electricity for a year. He explained that we would only need to cover 4% of our deserts with PV cells to provide the entire world’s energy needs.

Dr Luria warned us that conventional energy sources would eventually destroy our planet, and added that we had to focus on developing our use of solar energy. I am definitely a fan of solar energy now!