I really can't think of a renewable that doesn't involve the use of heat to make the materials used in it.

It is true that the military applications of renewable energy are very small, although the diversion of alcohol for military purposes, largely the entertainment of soldiers, is known.   This is probably because renewable energy has a very low energy density and is not widely utilized.

It is certainly arguable whether the prime use of nuclear technology is military however.   I wish that the military use of oil would lead to people calling for its ban.