# Direct energy weapon vs kinetic energy

Good day, I would love to ask this question. Lets say that I have a energy source capable of delivering 10^30 watts with capacitors to match it and I would like to use this energy as a weapon (sort of like a death star).

Now the question, is it realistic to deliver all this energy through laser as a direct energy deposition (like death star), or is it not realistic and the only way to deliver this energy is through using thet energy to accelerate some object near to c and using it as a kinetic energy weapon? (fast projectile)?

• The big issue is efficiency. Lasers are about 10% efficient in converting electricity to light. So you will get $10^{29}$ W of laser and $9\cdot 10^{29}$ W of heat - you better dissipate that heat efficiently, or you will be more vaporized than the target. Coilguns for accelerating masses are more efficient, but I have yet to see any good bounds in any paper. – Anders Sandberg Jan 27 at 1:37