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Rocket Delta V Power Budget Planner

The Rocket Delta V Power Budget Planner estimates electrical power and energy demand for systems active around a delta-v maneuver. It combines propulsion-support power, avionics, communications, and other loads, then applies a design margin and multiplies the result by maneuver duration.

The planner is useful for checking whether a battery, power bus, or generation system can support an electrically demanding burn sequence. It does not calculate chemical propulsion energy; instead, it models onboard electrical loads associated with the maneuver. For electric propulsion, enter the thruster and power-processing draw in the propulsion-support field so that the main load is represented directly.

Inputs

W
W
W
W
min
%
Result
—
Required power incl. margin
Base active load—
Margin allowance—
Energy for powered duration—

1. Enter propulsion-related load
Include thrusters, pumps, valves, heaters, or power-processing equipment that draws electrical power.

2. Add spacecraft loads
Enter avionics, communications, and any other loads active during the event.

3. Set powered duration
Use the time the listed loads remain active, in minutes.

4. Apply design margin
Enter the power margin used in your early design budget.

5. Review power and energy
Use required watts for bus sizing and watt-hours for battery or energy-storage checks.

Base load = Pprop + Pavionics + Pcomm + Pother Required power = Base load × (1 + Margin / 100) Energy = Required power × Duration(hours)

All entered loads are treated as simultaneous constant electrical loads over the powered duration.

What the result means

The main result is the electrical power capacity needed after applying the selected design margin.

Real power systems require time-resolved load profiles, conversion efficiencies, battery limits, thermal constraints, and generation changes during attitude maneuvers.

Given: 3,500 W propulsion/PPU, 450 W avionics, 180 W communications, 220 W other, 45 minutes, and 20% margin.

Calculation: Base load = 4,350 W. Required power = 4,350 × 1.20 = 5,220 W. Energy = 5,220 × 0.75 = 3,915 Wh.

Result: Plan for 5.22 kW of power and about 3.92 kWh for the modeled duration.

Does this calculate rocket engine thrust power?

No. It budgets onboard electrical demand. For electric propulsion, enter electrical thruster and power-processing consumption as part of the propulsion load.

Should standby loads be included?

Include any loads that remain active during the powered interval. Exclude loads that are definitely off.

Why are power and energy both shown?

Power determines instantaneous capacity, while energy helps size batteries or other storage for the event duration.

Does the margin apply to energy too?

Yes. Because energy is calculated from the margin-adjusted required power, the same margin is reflected in the energy total.

Can this model a changing load profile?

Not directly. For a varying profile, calculate separate phases and sum their energy requirements.