How do I install the Power Thermal Budget skill?

Run npx skillmds@latest add ashfordeou/power-thermal-budget in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Power Thermal Budget safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Power Thermal Budget?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Power Thermal Budget free to use?

Yes. Installing skills from SkillMD is free. This skill is licensed under Apache-2.

Who published Power Thermal Budget?

ashfordeOU (@ashfordeou) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Power Thermal Budget by ashfordeou — Agent Skill

Name: Power Thermal Budget
Author: ashfordeOU

Power Thermal Budget

Use when sizing spacecraft electrical power and thermal budgets per ECSS practice: estimate battery capacity from eclipse power draw, depth of discharge, and efficiency; size the solar array from daylight-only generation; and check power margins against spacecraft bus requirements. The skill covers orbit-period eclipse fractions, battery sizing, solar array sizing, and margin checks for power budgets. Trigger: power budget, thermal budget, eps, eclipse, battery sizing, solar array, spacecraft, orbit period, power margin.

ashfordeOU Updated Sep 17, 2026

File contents

Spacecraft Power / Thermal Budget (space-systems/subsystems/power-thermal-budget)

Use when the task is spacecraft electrical power system (EPS) budgeting: eclipse fraction from orbit geometry, battery sizing against eclipse demand, solar array sizing for daylight-only generation, and power margin checks.

Domain quick reference

Eclipse fraction: f = eclipse_min / orbit_period_min (0 < f < 1).
Battery capacity required (Wh): C = power_w * (eclipse_min/60.0) / (dod * efficiency).
Sizing margin: sized capacity must be >= required * (1 + margin); typical margin 0.20.
Solar array power (daylight-only generation): P_sa = power_w / (efficiency * (1 - eclipse_fraction)) * (1 + margin).
Power margin: margin = available/required - 1; typical minimum 0.20. ECSS-E-ST-20C and ECSS-E-ST-10C set the European baseline for EPS and systems engineering budgets.

Workflow

Determine the orbit period and worst-case eclipse duration; compute the eclipse fraction.
Size the battery from eclipse power draw, depth of discharge, and efficiency; apply the sizing margin.
Size the solar array from the day-side power demand and generation efficiency.
Check the power margin against the bus requirement.
Confirm the deterministic checks with the contract test scripts/test_power_thermal.py.

Pitfalls

Sizing the battery from average power instead of eclipse demand.
Forgetting depth of discharge and efficiency losses in battery capacity.
Assuming the array generates during eclipse.
Zero or inverted eclipse fractions (eclipse longer than the orbit period).

Behavior contract (gate 3)

The eclipse, battery, array, and margin logic is exercised by the gate 3 contract test: scripts/test_power_thermal.py against scripts/power_thermal_logic.py (stdlib unittest, offline). Run: python3 scripts/test_power_thermal.py

Compliance

Standards referenced, not reproduced: ECSS standards are freely downloadable (copyright ESA); summary-only per standards-map.yaml and brief 06.
compliance: STANDARDS-REF, gated: false.

---name: power-thermal-budgetdescription: Use when sizing spacecraft electrical power and thermal budgets per ECSS practice: estimate battery capacity from eclipse power draw, depth of discharge, and efficiency; size the solar array from daylight-only generation; and check power margins against spacecraft bus requirements. The skill covers orbit-period eclipse fractions, battery sizing, solar array sizing, and margin checks for power budgets. Trigger: power budget, thermal budget, eps, eclipse, battery sizing, solar array, spacecraft, orbit period, power margin.license: Apache-2.0---# Spacecraft Power / Thermal Budget (space-systems/subsystems/power-thermal-budget)Use when the task is spacecraft electrical power system (EPS)budgeting: eclipse fraction from orbit geometry, battery sizingagainst eclipse demand, solar array sizing for daylight-onlygeneration, and power margin checks.## Domain quick reference- Eclipse fraction: f = eclipse_min / orbit_period_min (0 < f < 1).- Battery capacity required (Wh): C = power_w * (eclipse_min/60.0) / (dod * efficiency).- Sizing margin: sized capacity must be >= required * (1 + margin); typical margin 0.20.- Solar array power (daylight-only generation): P_sa = power_w / (efficiency * (1 - eclipse_fraction)) * (1 + margin).- Power margin: margin = available/required - 1; typical minimum 0.20. ECSS-E-ST-20C and ECSS-E-ST-10C set the European baseline for EPS and systems engineering budgets.## Workflow1. Determine the orbit period and worst-case eclipse duration; compute the eclipse fraction.2. Size the battery from eclipse power draw, depth of discharge, and efficiency; apply the sizing margin.3. Size the solar array from the day-side power demand and generation efficiency.4. Check the power margin against the bus requirement.5. Confirm the deterministic checks with the contract test scripts/test_power_thermal.py.## Pitfalls- Sizing the battery from average power instead of eclipse demand.- Forgetting depth of discharge and efficiency losses in battery capacity.- Assuming the array generates during eclipse.- Zero or inverted eclipse fractions (eclipse longer than the orbit period).## Behavior contract (gate 3)The eclipse, battery, array, and margin logic is exercised by thegate 3 contract test: scripts/test_power_thermal.py againstscripts/power_thermal_logic.py (stdlib unittest, offline). Run:python3 scripts/test_power_thermal.py## Compliance- Standards referenced, not reproduced: ECSS standards are freely downloadable (copyright ESA); summary-only per standards-map.yaml and brief 06.- compliance: STANDARDS-REF, gated: false.

Frequently asked questions