Yes. Thrust is related to momentum while power to energy. So if you double the exhaust velocity, you double the thrust but quadruple the power needed. P =

Yes. Thrust is related to momentum while power to energy. So if you double the exhaust velocity, you double the thrust but quadruple the power needed. P = 0.5 * mdot * v_ex^2 T = mdot * v_ex A normal ion thruster might have ISP 4000 or 40 km/s exhaust velocity. From the rocket equation, if our mission requires 10 km/s delta vee, mass ratio is exp(10/40)=1.28. So out of every 1280 kg, 280 kg is propellant. If we have mass flow of 0.1 gram per second, thrust is 40000 m/s * 0.0001 kg/s = 4 N and power is 80 kW. Acceleration is about 0.27 km/s per day. Not so good for humans through Van Allen belts. But fine for deep space propulsion. 80 kW of solar cells with 200 W/kg weight efficiency would weigh 400 kg. This is ISS level power. So the spacecraft might have 280 kg of propellant, 400 kg of solar arrays, 600 kg of useful things.