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Power / Thermal / Budgets

Day / Night Energy Balance

Compare sunlight charging, eclipse energy draw, and battery reserve using a simple energy-balance teaching model.

High school
Time estimate
25–35 min
Complexity
developing
Maturity
pilot ready
Simulator readiness
implemented
Software available now
Implemented — sun/eclipse energy-balance teaching lab at `/twin/learn/activities/budget_battery_eclipse`. Not a battery safety certification or detailed chemistry model.
Open interactive activity
Curriculum map →Learn hub →Power / Thermal / Budgets overview →

Student path

  1. Set sun vs eclipse minutes (try a preset, then stress eclipse).
  2. Set battery Wh, solar charging power, and average load.
  3. Increase payload duty stress to see reserve drop.
  4. Copy evidence with mitigation ideas — teaching model only.

Learning outcomes

Student can relate sunlight vs eclipse time, average load, and stored energy to a remaining-reserve warning (teaching estimate).

  • Explain why eclipse duration matters for stored energy.
  • Connect higher payload duty cycle to higher average load and energy stress.
  • Propose one mitigation if reserve is low (reduce duty, shed load, more battery, or change operations).

Concept primer

Compare sunlight charging, eclipse energy draw, and battery reserve using a simple energy-balance teaching model.

Open the Day / Night Energy Balance lab at `/twin/learn/activities/budget_battery_eclipse` — local browser model (not cell-level battery chemistry).

Compute eclipse energy as E = P × t; compare to a battery energy capacity in Wh.

Interactive lab

Teaching-grade software activity slot — not a flight simulator or certified propagator.

Interactive lab

Sunlight vs eclipse energy (teaching)

Uses a single-orbit Wh estimate: surplus charging happens only when solar exceeds load in sunlight; eclipse draws from stored energy.

Orbit summary

Orbit period (model): 90 min · Sun ≈ 0.92 h, eclipse ≈ 0.58 h

Energy (approx.)

Surplus charging power
8.11 W
Estimated surplus energy in sun
7.4 Wh
Estimated eclipse draw
8.1 Wh
Net change / orbit
-0.7 Wh

Battery reserve (toy)

Healthy band

Ending SOC estimate: 71%

No mitigation needed in this toy orbit — reserves look adequate.

Local self-check

Assessment (practice only)

Use this as a self-check and discussion starter. It is local-only and not a grade.

Optional: attaches a local summary (completed / quick checks / checklist count).

Quick check

Multiple choice self-check

This is a local self-check to support discussion. It is not a grade.

Quick check: During eclipse, solar panels contribute roughly…

Quick check: If payload duty cycle increases but eclipse duration stays long…

Discussion prompt

Short answer (local only)

Write notes for yourself or your group. Nothing is submitted.

Short answer: Describe one mitigation if your reserve drops below the safe band (operations or design).

Checklist

Local checklist self-check

Use this to verify you covered key ideas. Nothing is submitted.

Checklist: Energy balance readiness (self-check)

0 / 4 checked

Local summary

Assessment summary (practice only)

Completion

0 / 4 sections complete

Quick checks

0 / 2 correct

Shown only to support self-check.

Checklist

0 / 4 items checked

Reminder

Local-only practice summary. Not a grade and not submitted anywhere.

What this preview is / is not

Assessment engine v0 boundary note

  • Student view (local practice): use this as a self-check and discussion starter.
  • Local-only preview/practice: your answers are not submitted.
  • No backend, no accounts, no roster, and no LMS integration.
  • Not a grade. No credential or official scoring is implied.
  • Teacher visibility into student answers is not implemented in MVPF8.
  • Evidence runtime engine arrives in Phase 9 (not in this preview).

Capture

Evidence capture (local-only)

Capture what you did, what changed, what you observed, and how you explain it. This stays in your browser unless you copy/share it manually.

Selected inputs

  • Sunlight duration: 55 min
  • Eclipse duration: 35 min
  • Battery nameplate energy: 90 Wh
  • Solar charge power (teaching): 22 W
  • Average load baseline: 12 W
  • Payload duty stress factor: 35%

Generated outputs

  • Effective average load (model): 13.89 W
  • Energy surplus in sun (approx.): 7.4 Wh
  • Energy drawn in eclipse (approx.): 8.1 Wh
  • Net energy change / orbit (approx.): -0.7 Wh
  • Ending state of charge (toy model): 71%
  • Reserve status: healthy

Checklist

Evidence checklist

0/4 checked

Evidence artifact (local-only)

Day / Night Energy Balance

Captured: 2026-05-16T07:38:32.810Z · Level: high_school · Track: budgets_resources

Summary

Copyable class summary

Copy a readable summary for class notes, or copy JSON for a structured record. Local-only: nothing is submitted.

Evidence artifact (v1)
Activity: Day / Night Energy Balance
Track: budgets_resources
Learner level: high_school
Captured: 2026-05-16T07:38:32.810Z

Mission brief:
Single-orbit teaching balance (not orbital illumination physics or battery chemistry certification).

Selected inputs:
- Sunlight duration: 55 min
- Eclipse duration: 35 min
- Battery nameplate energy: 90 Wh
- Solar charge power (teaching): 22 W
- Average load baseline: 12 W
- Payload duty stress factor: 35%

Generated outputs:
- Effective average load (model): 13.89 W
- Energy surplus in sun (approx.): 7.4 Wh
- Energy drawn in eclipse (approx.): 8.1 Wh
- Net energy change / orbit (approx.): -0.7 Wh
- Ending state of charge (toy model): 71%
- Reserve status: healthy

Checklist:
- [ ] Compared sunlight vs eclipse segments
- [ ] Related duty cycle to average load
- [ ] Named one mitigation if reserve is low
- [ ] Copied evidence with teaching boundary

Observations:
(not provided)

Reflection:
Mitigation I would try first if reserve went critical.

Model boundary note:
Local-only teaching model — not flight-grade EPS, thermal, or mass analysis; no battery certification claims; evidence is not submitted anywhere and is not a grade.

Policy reminder:
- Local-only capture. Not submitted anywhere. Not a grade.

Boundary note

Local-only teaching model — not flight-grade EPS, thermal, or mass analysis; no battery certification claims; evidence is not submitted anywhere and is not a grade.

Evidence capture

Expected outputs learners should be able to show after the lab (Phase 9 evidence engine preview available).

  • Sun / eclipse / orbit settings and average load
  • Energy generated in sun and energy drawn in eclipse (teaching Wh estimate)
  • Battery remaining or reserve status and one mitigation if low
  • Local self-check summary and copied evidence text

Reflection

Set sun vs eclipse minutes, battery capacity, average load, and payload duty; read generated vs consumed energy and reserve status.

Responses are not persisted in this preview unless a specific activity component adds storage later.

Assessment / quick check

Why can a mission look power-positive in sunlight but still fail in eclipse?

Teacher notes

Emphasize energy = power × time; eclipse is the “night” problem even if sun charging looks strong.

Teacher use

Anchor on energy = power × time. Ask why a sunny-average story can still fail during eclipse. Reinforce: no battery chemistry certification claims — this is a classroom estimator.

Next activity

Suggested progression from the mission learning path. Links avoid missing activity routes.

Curriculum map →Learn hub →