Toastmasters CC 7 Speech - The Power of the Sun

Delhi driver story…

Do you know every hour the sun beams onto Earth more than enough energy to satisfy global energy needs for an entire year?

Solar Energy or Sunlight is the source of all life on our planet. Since time immemorial, we have been tapping sunlight for our useful purposes. Greeks in the 7th century BC learnt to tap Sunlight using a simple magnifying glass. In the 18th century, we have succeeded in making Green Houses to boil water and cook rice. Solar cookers have been existence for over 50 years. It was only a few hundred years ago when we learnt what is known as the Photovoltaic Effect – creation of electric current in a material when it is exposed to light.

Think of what would you do if you were on a beach! With the vast Sea in the front, making castles in the Sand. Sand, available in abundance on the entire planet is a rich source of Silicon. Silicon is a material which shows the Photovoltaic Effect – creation of electric current in a material when it is exposed to light.

Silicon from the Sand is converted to small discs called Silicon wafers, much like Potato wafers. Silicon wafers are then combined to prepare small blocks called Silicon cells. And finally, the cells are combined together to prepare what are commonly known as Solar Modules. These modules are used both at our home roofs and at huge tracts of land to convert Sunlight into Electricity, popularly known as a Solar Power plant.

A Solar Power Plant was first used by NASA in its space exploration missions, including the International Space Station which is entirely powered from solar cells. As the technology became cheaper, its applications moved to Solar Power plants of a few Megawatts to small solar power systems for houses and entire villages. As a matter of fact, about ⅔ of the solar power installed around the world was installed within the last 2½ years.

The production of Silicon cells has increased by more than 40% in the past 5 years. At the same time, the installed capacity of solar power plants has also increased at similar rate. As on 2012, 31% of total solar capacity across the world is installed in Germany. Italy, US, China, Japan & Spain are among top 6 with 5-7% of installed capacity. India has put a humongous target of 20,000MW of solar power installation by the year 2022. Cost of installation of solar power systems has also reduced by more than 50% in the last 5 years.

A rose, however, does not come without its thorns. The technology has some drawbacks too. The most obvious is the non-availability of the Sun during night, which makes it essential to rely on battery for power storage leading to inefficiencies and increased cost. A solar power system can only convert 15% of sunlight to usable electricity, which is further reduced due to changing seasons and cloudy weather.

Nonetheless, with the rising costs of Coal and Petrol & Diesel, the balance has slowly started to weigh heavier towards Solar. Speaking of Diesel, let me conclude with a conversation I had with my friend some time back.

Friend conversation story…