1

A Lunar Fission Surface Power (FSP) System

Presented to:Nuclear and Emerging Technologies for Space

NETS 2009

James Werner/INL, Project LeadJune 15, 2009

Pre-Decisional, For Discussion Purposes Only

Pre-Decisional, For Discussion Purposes Only 2

History of Space Nuclear Power

• Fission Reactor Systems– SNAP-10A (launched 1965)– SP-100 (cancelled 1992)– Jupiter Icy Moons Orbiter

(cancelled 2005)– Fission Surface Power (Present)

• Radioisotope Power Systems– 44 Successful U.S. Radioisotope

Thermoelectric Generators (RTG) Flown Since 1961

– Some Examples:• Apollo SNAP-27 (1969-72)• Viking SNAP-19 (1975)• Voyager MHW-RTG (1977)• Galileo GPHS-RTG (1989)• New Horizons GPHS-RTG (2005)

SNAP-10A(Agena)

SNAP-27(Apollo)

SNAP-19(Viking)

Pre-Decisional, For Discussion Purposes Only 3

Recent interest in Fission Surface Power (FSP) to support moon / Mars exploration

• Continuous Day/Night Power for Robust Surface Ops• Same Technology for Moon and Mars• Suitable for any Surface Location

– Lunar Equatorial or Polar Sites– Permanently Shaded Craters

• Environmentally Robust– Lunar Day/Night Thermal Transients– Mars Dust Storms

• Operationally Robust– Multiple-Failure Tolerant– Long Life

• Highly Flexible Configurations– Excavation Shield Permits Near-Habitat Siting– Option for Above-Grade System or Mobile System (with

shield mass penalty)– Option for Process Heat Source (for ISRU or habitat)

Pre-Decisional, For Discussion Purposes Only 4

• Safe During All Mission Phases– Launched Cold, No Radiation Until Startup– Safe after Shutdown with Negligible Residual

Radiation• Scalable to Higher Power Levels (kWs to MWs)• Competitive Cost with PV/RFC

– Detailed, 12-month “Affordable” Fission Surface Power System Cost Study Performed by NASA & DOE

– LAT2 FSP and PV/RFC Options had Similar Overall Cost

– Modest Unit Cost Enables Multiple Units and/or Multiple Sites

• Technology Primed for Development– Terrestrial Reactor Design Basis– No Material Breakthroughs Required– Lineage to RPS Systems (e.g. Stirling) and ISS (e.g.

Radiators, Electrical Power Distribution)

Recent interest in Fission Surface Power (FSP) to support moon / Mars exploration

Pre-Decisional, For Discussion Purposes Only 5

Affordable Fission Surface Power System Study Reference Concept

• Modular 40 kWe system with 8-year design life suitable for global lunar and Mars surface applications

• Emplaced configuration with regolith shielding augmentation permits near-outpost siting (<5 rem/yr at 100 m separation)

• Approximately 7 metric tons and <60 m3 volume is a good match for Altair capability

Stowed3 x 3 x 7 m

Deployed

Pre-Decisional, For Discussion Purposes Only 6

Keys to Affordability• Reactor: low temperature, well known UO2 fuel, stainless steel construction, liquid

metal NaK coolant well-tested• Stirling power conversion: high efficiency at low temperature, 1980’s test experience,

RPS leverage• Heat rejection: ISS mechanical design heritage, simple water heat pipes• System: Power density of nuclear reactor allows heavier, simpler, more robust

components

Pre-Decisional, For Discussion Purposes Only 7

07 08 09 10 11 12 13 14 15 16 17 18 19 20

Tech Demo.Unit (TDU)ETDP

Devt. TestModels (DTM)

EngineeringModels (EM)Form, Fit & Function

FlightModels (FM)

Design

Life Test ≤5 yrs

Test

Des

Design

Design

Life Test ≤3 yrs

Fab

Fab

Fab

Fab

Study

Study

LaunchATLOATP CDR

PrimeContract

Non-nuclearTRL6

LSSMCR

Ref. ConceptSelection

PDR/NAR

Test

Test

Test

Ship

KSC

Full Power, Full-Scale System TestStructural & Environ. QualificationEngineering Core Criticals

Subsystem, Module, and SystemFlight Acceptance Testing

1/4 Power, Full-Scale System TestPrim. & Sec. Fluid Test LoopsCoupon/Component Radiation Tests

1/2 Power, Full-Scale System TestEnviron. Eval. (Radiation, Vib, etc.)Physics Core Criticals

Task FY

LSSSRR

Revised 8/1/08

Notional FSP Flight Development Schedule

Pre-Decisional, For Discussion Purposes Only 8

2.0 Concept Definition 2.1 Concept SelectionLead: Lee Mason (GRC)

2.2 Modeling and Tool DevelopmentLead: Scott Harlow (DOE)

1.0 Fission Surface Power Systems Project Management

Project Manager: Don Palac (GRC)Principal Investigator: Lee Mason (GRC)DOE Lead: Scott HarlowMSFC Lead: Mike HoutsBusiness Analyst: Annie Delgado-Holton (GRC)

4.0 Risk Reduction

4.1 System Risk ReductionLead: Lee Mason (GRC)

4.2 Primary Test Circuit Risk Red.Lead: Mike Houts (MSFC)

4.3 Reactor Component & Irradiation TestingLead: Scott Harlow (DOE)

4.4 Power Conversion Risk ReductionLead: Lee Mason (GRC)

4.5 Heat Rejection Risk ReductionLead: Don Jaworkse (GRC)

Fission Surface Power Project

Pre-Decisional, For Discussion Purposes Only 9

FSP Technology Project:Concept Definition

Radiator & Deployment System

Reactor Heat TransportLoop Integration

Stirling Convertor Concept

Reactor CoreModeling

Stirling CFDModeling

Radiator ModelValidation

Heat Rejection

Pre-Decisional, For Discussion Purposes Only

10

FSP Technology Project: Component Pathfinders

1 kWt RadiatorDemo Unit

Ti-H2O Heat Pipe Life Test

2 kWe NaK Stirling System

10 kWe StirlingAlternator Test Rig

NaK Electromagnetic Pump

20 kWt NaK Reactor Simulator

Reactor

2 kWe Direct Drive Gas Brayton

PowerConversion

Pre-Decisional, For Discussion Purposes Only 11

Notional TDU Test Layout in GRC Vacuum Facility #6

Technology Demonstration Unit – The Core of the Fission Surface Power Systems Project

• Demonstrate system-level technology readiness in an operational environment

• ¼ power, full scale hardware demonstration

Pre-Decisional, For Discussion Purposes Only 12

Lunar Surface Systems Architecture Planning

FSP Off-Loaded & Buried

FSP Remains on Lander

Notional Concept for FSP-Lander Delivery

Pre-Decisional, For Discussion Purposes Only 13

Summary

• FSP has many advantages– Day/night power– Location independence– Environment tolerance– Moon/Mars commonality– High power, low mass

• Mission integration options are plentiful– Buried or Landed, Early or

Later, With or without PV– Minimal impact on crew– Major impact on surface

capabilities

FSP Technology Development Projectis addressing the fundamental issues

• Affordability = Conservative, Simple, Robust– Known materials, generous

margins– Modest requirements– Self-regulating controls– Fault tolerant, designed to

recover from anomalies– Hardware-rich test program– Low risk, accept mass

penalties if necessary

Pre-Decisional, For Discussion Purposes Only 14

Positive Press• NASA News Release “NASA Developing Fission Surface Power

Technology” Katherine Martin (9/10/08)– Picked up by Dozens of Internet Sites including SpaceRef and Science Daily– 100’s of Blogs… mostly supportive and positive

• DiscoveryChannel.com “NASA Eyes Nuclear Reactor for Moon Base” Irene Klotz (9/15/08)

• Space.com “NASA Eyes Nuclear Power for Moon Base” Jeremy Hsu (9/17/08)

• Athens Post “Athens Business to Develop Power Converter for NASA” Amanda Liles (10/6/08)

• Popular Science Magazine “Gone Fission” Dawn Stover (Dec 2008 Issue)