[hughes]

They may be reserving a large portion of the generated heat for thermal control. It's extremely cold on Titan.

[jacobush]

I guess, but it all (well, 99.999999% and more) gets converted to heat anyway when you use the electricity. So ... I don't understand.

[lmilcin]

I guess the reason might be it is pretty difficult to make efficient conversion from heat to electricity that would also be very reliable.