January 19, 2016

Space missions by various countries use solar energy to power their spaceships.

With the fast depletion of non renewable energy resources, the next big energy switch would be to solar energy (and it is already happening all around us). From watches to automobiles and our homes, solar energy is gradually replacing the traditional energy sources. This is happening for a good reason, Solar energy is the most lasting energy option that we have (Sun is likely to live for another 4-5 billion years).

Many of you may not be knowing that solar energy has a very serious and lasting application many millions of miles away from us, in outer space. Do you recall those huge panels attached to every single spacecraft in the award winning movie “Gravity”. These are the solar panels we are talking about here that power every spacecraft now in the space, virtually every single one of them.

Why do Spacecrafts use solar energy
There are many reasons for that. The traditional sources of energy for such aerial vehicles used to be batteries which are heavy, have limited life (even the most efficient ones) and limited power output (as compared to their size), whereas a spacecraft has a long life and high energy needs to run all its functions smoothly. Spacecrafts obviously need an everlasting energy source which has the enough power production potential to provide for all the energy needs of a spacecraft. There is not a better source than solar energy for this purpose.
Space packs 2 billion times more solar energy than what we receive on earth due to the earth’s radiation filtration system. This is the precise reason for which virtually all spacecrafts are equipped with huge solar energy panels to capture the solar energy from the Sun.

How do they do it
A spacecraft has huge energy needs (despite its energy efficient design) to run all the systems on-board. To meet this end, each spacecraft is equipped with huge solar penal plates (usually attached to the main body with some hoist). These solar panels are installed on platforms which are movable and always kept pointing towards the Sun, irrespective of the direction of the spacecraft.

The number, size and type of these solar panels are kept according to the output required from them. The combined input from these solar panels in then used to generate electricity to run the systems in the spacecraft.

On the flip side, solar panels have a life (though much longer than other on-board spacecraft energy sources) and they can generate solar energy as long as they are at a suitable distance from sun and pointing towards it. Over time, as the spacecraft move away from the Sun, the solar panels lose their capacity to produce power and gradually the spacecraft loses its functions for the lack of power.

Solar panels have obvious advantages over sources like being non radioactive (unlike RTG’s), light weight, long life and energy efficient. They are likely to find even more applications in time to come even within the outer space.