Assessment of Space Solar Power for Defense Applications

E2S2May 12, 2011

Authors

The Tauri Group David Kerner Jason Hay Carie Mullins Suzette Johnson Mandy Sweeney Carissa Christensen, Managing Partner

Topics

Purpose of this Analysis Energy Concerns Defense Energy Applications Space Solar Power (SSP) Systems Overview Analysis: Does This Fit? Defense Application Characteristics Findings Conclusion Analysis Methodology Details

Purpose

Provide technology-agnostic tool for evaluating energy technologies to support DoD missions

Support development of capabilities appropriate to defense mission needs

Provide background on defense energy vulnerability

Provide analysis of SSP applicability to DoD needs and application areas

National Security Energy Vulnerabilities

Systemic, nation-wide reliance on limited, non-renewable resources

Fluctuations, shortfalls, and restrictions from human causes

Political, economic, environmental, military, and infrastructure risks

Insufficient plans for future, long lead times to develop adequate substitutes

DoD depends on the same resources as the nation’s economy

Nation-wide push to find energy alternatives that reduce vulnerabilities

DoD’s Energy Resilience

Lacks resilience to energy resource fluctuations

Leading U.S. energy user

About 1% of its energy from renewable sources

Fully burdened cost of fuel: DoD can pay > $400 per gallon

Defense Energy Applications

Fixed facilities Long-term installations Short-term installations Forward engagement bases Sensor systems

Mobile platforms Ground Air Sea (surface) Submarine

Sources: U.S. Air Force, U.S. Army, and U.S. Navy

Space Solar Power Systems

Potential renewable alternative energy source for defense applications?

Source: NASA

Space Solar Power Systems: Microwave vs. Laser

Microwave transmission systems• Efficient energy conversion on the ground• Minimal atmospheric attenuation• Low power density• Large apertures in space and rectennas on the ground

Laser transmission systems• Higher beam power density and smaller footprint for beam

collection• Multiple conversion methods• Atmospheric losses• Lower conversion efficiencies

Space Solar Power Systems: Non-GEO vs. GEO

Geostationary systems• Constant coverage• Limited eclipse periods• Power to multiple locations within the satellite’s field of view

Non-Geostationary systems• Power to multiple locations around globe• Reduced free space loss and launch cost• Easier to target• Requires a pulse power system with on-ground storage or

supplemental power• Some orbits cannot provide power during the night

Analysis: Does This Fit?

Three dimensional matrix: applications, characteristics, SSP evaluation

Allows consistent assessment of other energy technologies Does not consider economic, political, environmental, or

social factors

•Types of SSP Systems•Laser GEO•Laser Non-GEO•Microwave GEO•Microwave Non-GEO

Evaluation Ratings

Green = Current technology in an optimized system meets the characteristic needs for a application area.

Yellow = There are some technical challenges that need to be overcome, and a development pathway to overcome these challenges exists.

Red = Technical challenges are significant, potentially insurmountable, and development pathways are not identified.

Defense Application Characteristics

Character: load, duration, periodicity Position: operational footprint, range, speed, distributed

vs. centralized Time: deployment, engagement, removal Logistics: materiel deliveries, infrastructure, personnel,

skill sets, maintenance, deployment environment Stealth Security

Findings

• SSP may increase energy security at military facilities• Harder to disrupt transmission between the satellite

and ground station• Could reduce the need for fuel convoys• Steady power supply may enhance facility safety and

security in a hostile environment• Technology and application-specific analysis is required

to assess if an SSP concept has a net positive or negative impact on security

SSP is a possible, though technically challenging, alternative to conventional, non-renewable energy resources for defense

Findings: Advantages, Challenges, and Unknowns

• Can be deployed anywhere on the globe• Provides high levels of centralized power• May reduce field maintenance and logistical burden

SSP advantages

• Deployment and removal time• Deployment environment safety and security• Infrastructure, real estate, and personnel

SSP challenges

• Does it reduce energy vulnerability?

SSP unknowns

Findings: Details

Fixed Facilities Best Application for SSP

Large facilities have the real estate and infrastructure for Laser or Microwave systems

Best fit is facilities with long deployment timelines and multi-year missions

Geostationary systems are ideal for constant power

Mobile Platforms Pose Greater Technical Challenges

Laser systems are necessary due to smaller footprint Still requires large surface area (e.g. large ship)

Advanced beam tracking necessary; easier with slower vehicles

Alternative approach could include centralized facility with synthetic fuel plant

Challenges: Rapid Deployment and Removal

U.S. military applications require rapid deployment and removal

Long lead times for system construction

Retasking reduces deployment time, but current capabilities do not meet some requirements

Challenges: Deployment Environment, Stealth, and Security

Military applications may involve austere or hostile environments Satellites and ground systems are

attractive targets Rectennas and solar arrays tend

to be fragile and require hardening or shielding

Current power beaming technologies would reveal system locations and may provide information on capabilities

Challenges: Infrastructure and Personnel

SSP is best suited for high-power, centralized systems Requires large power distribution systems Several military applications do not have access to this

infrastructure or the real estate to build it

Distributed SSP systems for mobile applications Requires advanced beam tracking systems Requires applications that use low-power, diffuse beams

Skilled workforce to maintain ground systems may not be available on small bases or mobile platforms

Conclusion

Most promising application: Powering fixed facilities with GEO satellites

Mobile applications are also possible, but technically challenging

SSP may reduce the U.S. military’s energy vulnerability, but there are significant challenges, costs, and risks

Further analysis is needed to compare economic considerations versus other alternative technologies

Analysis tool can provide comparative analysis of energy systems with respect to national security needs Critical to remember that the mission drives the technology

Analysis Methodology Details:Defense Energy Application Categories

Fixed facilities Long-term installations Short-term installations Forward engagement bases Sensors

Mobile platforms Ground Air Sea (surface) Submarine

Analysis Methodology Details:Defense Energy Application Characteristics

Character: Load – the level of energy demand Duration – how long demand lasts Periodicity – the character of the demand, e.g., continuous, at regular

intervals, as-needed, or for surge requirements

Position Operational footprint – area occupied by a fixed application Range – distance mobile application may travel from point of origin Speed – how fast a mobile application will travel Distributed vs. centralized – the manner with which energy may be

provided throughout a facility or mobile platform

Analysis Methodology Details:Defense Energy Application Characteristics

Time Deployment – the time in which a facility or platform is made

ready for operation Engagement – how long the facility or platform may be

operationally engaged Removal – the time in which a facility or platform is removed

from operation

Analysis Methodology Details:Defense Energy Application Characteristics Logistics

Materiel deliveries – the nature of materiel supply requirements, including delivery frequency, dependability, and quantity

Infrastructure – the type of infrastructure and degree to which a facility or platform is reliant upon it

Personnel – typical number of personnel Skill sets – typical range of skills available Maintenance – degree to which maintenance capabilities are

available and performed Deployment environment – characteristics of the environment in

which a facility or mobility platform operates

Stealth – degree to which a facility or mobility platform may need to operate covertly

Analysis Methodology Details:Defense Energy Application Characteristics Security – multi-faceted

How well a physical installation or mobility platform is protected from hostile and/or dangerous conditions

How well the operational capabilities of an installation or mobility platform are protected from hostile and/or dangerous conditions

Security capabilities enabled by energy systems/resources The vulnerabilities of an installation’s or mobility platform’s

energy system/resources to hostile and/or dangerous conditions Vulnerabilities posed to the installation or mobility platform by the

physical presence of energy systems/resources Vulnerabilities created by the use of energy systems/resources Operational and strategic vulnerabilities associated with reliance

on an energy system/resource