NASA writes to say

As the electrical power becomes less and less, power loads on the spacecraft must be turned off in order to avoid having demand exceed supply.

A lead battery would 'die' if demand were to exceed supply for any sustained duration ; What happens to an RTG in the same situation?


As you demand more current, the voltage goes down. You eventually brown-out the system. The RTG doesn't care. If you then reduce the load, the voltage goes back up.

You cannot drain an RTG like a battery. Its power output depends only on its radioactivity (which goes down over time), the efficiency of the thermocouples (which also goes down a little over time), and the temperature of the sink.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.