Physics Correction (March 2026)
Original estimate: 32% electrical, 62% thermal.
Revised: 10% electrical, 90% thermal.
Why: Gamma passes through thin layers. Need ~4cm scintillator to capture 80%. Scint→PV chain is ~5% efficient, not 30%.
The SE Cell is primarily a thermal device with electrical bonus.
Revised Budget (Co-60, 1g = 17.5 W)
| Beta (11%) | 1.9 W |
| → Betavoltaic 10% | 0.2 W ⚡ |
| → Heat | 1.7 W 🔥 |
|
| Gamma (89%) | 15.6 W |
| → Scint+PV (5%) | 0.6 W ⚡ |
| → Heat | 15.0 W 🔥 |
|
| Heat gradient → TE (6%) | 1.0 W ⚡ |
|
| ELECTRICAL: | 1.8 W (10%) |
| THERMAL: | 15.7 W (90%) |
Layer Physics
Beta: Stops in 2mm. Cannot penetrate ANY solid.
Gamma: Penetrates cm of material. Scintillator must be BULK (~4cm) to capture 80%.
Heat: ALL absorption → heat. Conducts outward. TE captures gradient.
Light: Scintillator visible photons → PV or fiber.
Why Thermal-Primary Works
Home energy: ~64% thermal (heating, hot water, cooling).
A 90% thermal device matches home needs better than 30% electrical would.
SE Cell replaces furnace + water heater + partial electricity.
Scale: 50g Co-60
Electrical: ~90 W — lights, electronics
Thermal: ~785 W — heating, hot water, absorption cooling
Unit: ~20kg, filing cabinet size. Replaces gas furnace + water heater + ~$100/mo electric.
Cascade Lifecycle
Yr 0–5: Home (875W)
Yr 5–10: Workshop (438W)
Yr 10–15: Greenhouse (219W)
Yr 15–20: Sensors (109W)
End: Ni-60 (stable nickel)
One capsule, decades of thermal value.