Radioisotope Thermo-electric Generator: Why in the News?
In January 2021, the UR Rao Satellite Centre (URSC) of Indian Space Research Organization (ISRO) invited proposals for the three phase development of a 100 Watt Radioisotope Thermo-electric Generator (RTG).
UR Rao Satellite centre is ISRO’s lead centre for design, development, fabrication and testing of all Indian made satellites. Now it would be using Radioactive Thermoelectric generators for power generation and thermal management of various space missions.
All about Radioisotope Thermo-electric Generator (RTG):
Radioisotope Thermoelectric Generator is a kind of a nuclear battery using thermocouple to convert the heat released by decay of radioactive material into electricity. Seeback effect governs it and it generally has no movable parts.
(The “Seebeck effect” is a phenomenon in which a temperature difference between two dissimilar electrical conductors or semiconductors produces a voltage difference between the two substances.)
Working benefits of RTG:
- To know about the working of RTG let us know the working of a normal satellite:
- The normal satellites are launched in multiple stages. The first stage being the strap on boosters and in the second stage these are loosened by the satellites. In Indian satellites Vikas Liquid Engine is used in the second stage. The third stage is reached after detaching the second stage and finally the satellite is sent into space. The energy used is Solar Energy in normal satellites.
- Like other satellites use heavy carriers for energy generation making the satellites bulky, RTG systems use thermocouples and natural decay of radioactive isotopes into electrical energy. This makes them less bulkier.
- They are reliable and maintenance free because the moving parts in thermocouples that cause failure of machinery are absent in RTG system