Spacecraft Non-Nuclear Power Sources

(Updated 5 December 2012)

Batteries

Silver Oxide-Zinc Primary Battery (Non-Rechargeable)

Energy Density (mass): 130 watt-hours/kg (58.97 watt-hours/lb)
Energy Density (volume):
360 watt-hours/dm3 (5.9 watt-hours/in3)
Storage Temperature: 0° to 30° C
Operating Temperature: 0° to 40° C
Storage Life: 30-90 days if wet cell, 5 years if dry cell

References:
Spacecraft Power Systems by David W. Miller and John Keesee (PDF)

Lithium Sulfur Dioxide (Li-SO2) Primary Battery (Non-Rechargeable)

Energy Density (mass): 220 watt-hours/kg (99.79 watt-hours/lb)
Energy Density (volume):
300 watt-hours/dm3 (4.92 watt-hours/in3)
Storage Temperature: 0° to 50° C
Operating Temperature: -50° to 75° C
Storage Life: 10 years

References:
Spacecraft Power Systems by David W. Miller and John Keesee (PDF)

Lithium Carbon Monofluoride (Li-CFx) Primary Battery (Non-Rechargeable)

Energy Density (mass): 210 watt-hours/kg (95.25 watt-hours/lb)
Energy Density (volume):
320 watt-hours/dm3 (5.24 watt-hours/in3)
Storage Temperature: 0° to 10° C
Operating Temperature: Up to 82° C
Storage Life: 2 years

References:
Spacecraft Power Systems by David W. Miller and John Keesee (PDF)

Lithium Thionyl Chloride (Li-SOCl2) Primary Battery (Non-Rechargeable)

Energy Density (mass): 275 watt-hours/kg (124.74 watt-hours/lb)
Energy Density (volume):
340 watt-hours/dm3 (5.57 watt-hours/in3)
Storage Temperature: 0° to 30° C
Operating Temperature: -40° to 70° C
Storage Life: 5 years

References:
Spacecraft Power Systems by David W. Miller and John Keesee (PDF)

Silver Oxide-Zinc Secondary Battery (Rechargeable)

Energy Density (mass): 90 watt-hours/kg (40.82 watt-hours/lb)
Energy Density (volume):
245 watt-hours/dm3 (4.01 watt-hours/in3)
Storage Temperature: 0° to 30° C
Operating Temperature: 0° to 20° C
Storage Life: 30-90 days if wet cell, 5 years if dry cell
Max. Discharge Cycles: 200~

References:
Spacecraft Power Systems by David W. Miller and John Keesee (PDF)

Nickel-Cadmium (Ni-Cd) Secondary Battery (Rechargeable)

Energy Density (mass): 35 watt-hours/kg (15.88 watt-hours/lb)
Energy Density (volume):
90 watt-hours/dm3 (1.47 watt-hours/in3)
Storage Temperature: 0° to 30° C
Operating Temperature: 0° to 20° C
Storage Life: 2 years if wet cell, 5 years if dry cell
Max. Discharge Cycles: 20,000~

References:
Spacecraft Power Systems by David W. Miller and John Keesee (PDF)

Nickel-Hydrogen (Ni-H2) Secondary Battery (Rechargeable)

Energy Density (mass): 75 watt-hours/kg (34.02 watt-hours/lb)
Energy Density (volume):
60 watt-hours/dm3 (0.98 watt-hours/in3)
Storage Temperature: 0° to 30° C
Operating Temperature: 0° to 40° C
Storage Life: 2 years if wet cell, 5 years if dry cell
Max. Discharge Cycles: 20,000~

Notes: Used on the International Space Stations’ Energy Storage Subsystem (ESS), Messenger spacecraft, Mars Odyssey, Mars Global Surveyor, and both sets of Hubble Space Telescope batteries (originals that lasted 19 years, and the 2009 replacements).

References:
Spacecraft Power Systems by David W. Miller and John Keesee (PDF)

Solar Power

1969-1970s era Silicon Photovoltaic Cells (Skylab Array)

Skylab ATM Arrays: 10,060W at EOL
Skylab OWS Arrays:
118.27 m2 array area, 10,496W at EOL
Efficiency: 6.489% at End of Life (Based on OWS Array)


References:
Skylab Electrical Power System by Roy Lanier, Jr. (646~ kb PDF)

1995-2000s era Silicon Photovoltaic Cell (ISS Array)

Efficiency: 14.5%

References:
International Space Station Electric Power System Brochure, Boeing (1.5~ MB PDF)

Fuel Cells

Gemini Fuel Cells (General Electric PEM)

Nominal Power Rating: 1000W

Specific Reactant Consumption: 0.4 kWh/kg
Operating Lifetime: 200> hours
Operating Temperature: 21°C
Mass: 73.4 lbs (33.29 kg)
Specific Energy/Mass: 30~ W/kg

References:
2011 Human Spaceflight Fuel Cell Roadmap (1.5~ MB PDF)

Pratt & Whitney PC3A-2 (Apollo CSM)

Nominal Power Rating: 1500W at 28V (53.57A)
      Consumption: 1.122 lb/hr of O2, 0.14135 lb/hr of H2 (1.26335 lb/hr of reactants or 0.573046 kg/hr)
      Specific Consumption: 0.000842 lb/Watt-hr (0.000382 kg/Wh) of reactants
      Output: 1.263 lb/hr of H2O produced (0.000842 lb/water per W)

Overload Power Rating: 2300W at 20.5V (112.19A)
      Consumption: 2.04 lb/hr of O2, 0.257 lb/hr of H2 (2.297 lb/hr of reactants or 1.0419 kg/hr)
      Specific Consumption: 0.000999 lb/Watt-hr (0.000453 kg/Wh) of reactants
      Output: 2.297 lb/hr of H2O produced (0.000999 lb/water per W)

Dimensional Envelope: 22” diameter x 44” length (57 cm diameter x 112 cm length)
Operating Lifetime: 400> hours
Operating Temperature: 204°C
Volume:
Mass: 240.3 pounds (109 kg)
Specific Energy/Mass: 13.76~ W/kg

Notes: The first PC-3A flight-ready unit was delivered in 1962, and 92 production units were delivered by the end of 1969. 54 units flew on 18 missions and accumulated 10,750 hours of flight time.

Reference:
Report of Apollo 13 Review Board: APPENDIX A: Baseline Data, Apollo 13 Flight Systems and Operations (PDF Excerpt)
FCR-1656 Final Report: Lightweight Fuel Cell Powerplant Components Program, 22 Feb 1980 (1.16~ MB PDF Excerpt)
FCR-3142 Topical Report: Electrochemical Energy Storage for an Orbiting Space Station, Dec 1981 (4~ MB PDF Excerpt)
2011 Human Spaceflight Fuel Cell Roadmap (1.5~ MB PDF)

Pratt & Whitney PC8B Series

Notes: The PC8B series was developed under P&W in-house sponsorship to improve performance of their fuel cells.

PC8B-1 was the first powerplant incorporating low-temperature, matrix-type alkaline cells configured for a space application. Cell active area of 0.4 ft2 (371.6 cm2) was the same as Apollo, and the system maintained compatibility with the Apollo Service Module’s mounting structure and ancillary connections.

PC8B-2 was identical to the PC8B-1, except for the interface panel and mounting structure being modified for compatibility with the USAF Manned Orbiting Laboratory (MOL) vehicle.

PC8B-3 was a repackaged version designed in 1969 with a new, high power density stack of 0.508 ft2 (464.5 cm2) active area. Operated as a demonstration unit for a year, accumulating 97 starts and 6,000 hours on reactants. Rated power was 2.5 kW.

PC8B-4 was an improved version of the PC8B-3 with a better cooling system and rated power of 4.5 kW.

Reference:
FCR-1656 Final Report: Lightweight Fuel Cell Powerplant Components Program, 22 Feb 1980 (1.16~ MB PDF)
FCR-3142 Topical Report: Electrochemical Energy Storage for an Orbiting Space Station, Dec 1981 (4~ MB PDF Excerpt)

Pratt & Whitney PC8C Series

Nominal Power Rating: 5 kW

Notes: Built in 1971 with a high power density stack of 0.508 ft2 (471.9 cm2) active area. Used as a demonstrator for two years with 100 self-energized starts.

Reference:
FCR-1656 Final Report: Lightweight Fuel Cell Powerplant Components Program, 22 Feb 1980 (1.16~ MB PDF)

Pratt & Whitney PC15B Series

Notes: Developed for the USN, with a power rating of 20 kW.

Reference:
FCR-1656 Final Report: Lightweight Fuel Cell Powerplant Components Program, 22 Feb 1980 (1.16~ MB PDF)

Pratt & Whitney PC17 Series (Space Shuttle)

Nominal Power Rating: 7 kW
Overload Power Rating: 12 kW
Dimensional Envelope: 14” high, 15” wide, 40” long
Operating Lifetime: 5,000> hours
Operating Temperature:
90°C
Mass:
255 pounds (115.66 kg)
Specific Energy/Mass:
60.5 W/kg

Notes: The Orbiter fuel cell program began in January 1974, with manned flight qualification in June 1979. Apparently PC17B was an early developmental fuel cell, with the first flown units being PC17C.

Reference:
FCR-1656 Final Report: Lightweight Fuel Cell Powerplant Components Program, 22 Feb 1980 (1.16~ MB PDF)
FCR-3142 Topical Report: Electrochemical Energy Storage for an Orbiting Space Station, Dec 1981 (4~ MB PDF Excerpt)
2011 Human Spaceflight Fuel Cell Roadmap (1.5~ MB PDF)
Shuttle Reference, Orbiter EPS Powerplants (HTML LINK)

Pratt & Whitney PC15 Series (USN DSRV)

Nominal Power Rating: 30kW
Overload Power Rating: Unknown
Dimensional Envelope: 14” diameter x 72” length
Volume: 5.5 cubic feet
Mass: 391 lbs

Notes: Developed for the USN DSRV program.

Reference:
FCR-1656 Final Report: Lightweight Fuel Cell Powerplant Components Program, 22 Feb 1980 (1.16~ MB PDF)
FCR-3142 Topical Report: Electrochemical Energy Storage for an Orbiting Space Station, Dec 1981 (4~ MB PDF Excerpt)

H2/O2 Fuel Cell (Theoretical)

Theoretical Maximum Output (at 100% efficiency): 1,620 Watt-Hours/lb of reactants

References:
Spacecraft Power Generation by William C. Cooley, NASA (24-26 August 1960)