Pump power is the power of the pump typically expressed in watts. A high pressure pump on a Saturn V class rocket has a power output of about a hundred megawatts. A high pressure pump for a five kilogram rocket has a power output of two hundred watts. Pump power is high because of the voracious appetites that rocket engines have and the high pressure boost they require. The power to require a mass of liquid is proportional to the required boost and inversely proportional to its density.

Given exhaust velocity, combustion ratio, exhaust molecular, fuel mass ratio, fuel molecular, liftoff acceleration, mass, oxidizer mass ratio, oxidizer molecular, propellant mass ratio, propellant molecular, propellant usage, pump efficiency, reactant propellant usage and working temperature pump power can be calculated which is in turn used to calculate pump cost and pump mass.

propellant energy = propellant usage * pump efficiency * working temperature * 8,314 J * K / kmol / 0.2

combustion exhaust = combustion ratio / exhaust molecular

uncombustion = 1.0 - combustion ratio

pump energy = propellant energy * propellant mass ratio / propellant molecular + propellant energy * reactant propellant usage * ( fuel mass ratio * ( uncombustion / fuel molecular + combustion exhaust ) + oxidizer mass ratio * ( uncombustion / oxidizer molecular + combustion exhaust ) )

fuel flow = mass * liftoff acceleration / exhaust velocity

pump power = pump energy * fuel flow
 

pump cost = pow( ( pump power density / 160,000 ), pump density scale ) * pow( ( pump power / 10,000,000 ), structure mass scale ) * ten megawatt price

pump mass = pump power / pump power density
 
 

This is used in pumped rocket and rocket cost.
 
 

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