The American space agency (NASA) has approved the development of ultra-compact radioisotope thermoelectric generators (RITEG) by the Rochester Institute of Technology. It is assumed that they will be used in cubesats and other next-generation technology, the application of which will be found in deep space – where there is too little light for solar power cells.
What are RITEGs needed for?
Most satellites in operation use solar panels to convert light into electricity for power. Although they do their job well, in deep space, for example – beyond the orbit of Mars, or on the Martian surface itself, where sand storms rage, there is often too little light, so energy from solar cells is not enough.
An alternative in the form of RITEG makes it possible to use thermocouples to generate electricity from the heat released during the decay of radioisotopes. The principle has been known for a long time and is widely used on Earth.
The problem with such generators is that they are quite bulky. For example, each pair used in the Perseverance rover has a diameter of 64 cm, a length of 66 cm, and a weight of 45 kg. Each contains 4.8 kg of plutonium dioxide. As a result, RITEG can be used only in rather large spacecraft. For example, the Perseverance is a car the size of an SUV.
According to NASA, the specific mass energy capacity of the new project, as compared to the standard multipurpose RITEG, will increase from 3 to 30 W/kg, provided the volume is reduced by several orders of magnitude – from 212 to 0.2 liters.
Why is this important?
If the new technology can be brought to practical use, it could power future missions to Jupiter, power equipment in perpetually shadowed craters, lunar polar regions or cubesats – without the need for additional sources.
For example, this will make it possible to implement the Flagship Uranus mission to Uranus much more successfully, within the framework of which it will be possible to send a whole fleet of small satellites to the planet to provide research from different angles, “relay” communication and perform other tasks.
