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Stella, Paul

Publications and source records attributed to Stella, Paul.

16 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Development of High-Performance Solar Cells for the Jupiter and Saturn Environments

The planetary science community is interested in targets far from the Sun. Solar arrays are relatively low-cost, readily available, highly reliable. However, high-AU environments are challenging for solar arrays e.g. Jupiter: high radiation and 3-4% of one sun Saturn: milder radiation but only 1% of one sun. Currently, solar arrays for low irradiance low temperature (LILT) are typically large and massive, e.g. ~600kg for planned Europa Clipper. There is a need for cells optimized for Jupiter and/or Saturn.

Boca, Andreea↗
NASA NTRS2018

Development of High-Performance Solar Cells for the Jupiter and Saturn Environments

Many of the mission targets that NASA and the planetary-science community are interested in are located in deep space, in the 5-10AU range. This provides compelling motivation to develop solar cells and arrays that are highly efficient in low irradiance low temperature (LILT) environments. We give several examples of the iterative process our team has employed to develop cell designs that optimize the performance at LILT. We also provide results on advanced-architecture devices that have already demonstrated very high efficiencies in the Jupiter and Saturn LILT and radiation environments, specifically four-junction inverted metamorphic and triple-junction upright metamorphic solar cells, respectively.

Boca, Andreea↗
NASA NTRS2017

Solar Arrays for Low-Irradiance Low-Temperature and High-Radiation Environments

This is the Base Period final report DRAFT for the JPL task 'Solar Arrays for Low-Irradiance Low-Temperature and High-Radiation Environments', under Task Plan 77-16518 TA # 21, for NASA's Extreme Environments Solar Power (EESP) project. This report covers the Base period of performance, 7/18/2016 through 5/2/2017.The goal of this project is to develop an ultra-high efficiency lightweight scalable solar array technology for low irradiance, low temperature and high-radiation (LILT/Rad) environments. The benefit this technology will bring to flight systems is a greater than 20 reduction in solar array surface area, and a six-fold reduction in solar array mass and volume. The EESP project objectives are summarized in the 'NRA Goal' column of Table 1. Throughout this report, low irradiance low temperature (LILT) refers to 5AU -125 C test conditions; beginning of life (BOL) refers to the cell state prior to radiation exposure; and end of life (EOL) refers to the test article condition after exposure to a radiation dose of 4e15 1MeV e(-)/cm(exp 2).

Boca, Andreea↗
NASA NTRS2012

JUNO Photovoltaic Power at Jupiter

This paper summarizes the Juno modeling team work on predicting the Juno solar array performance at critical mission points including Juno Orbit Insertion (JOI) and End of Mission (EOM). This report consists of background on Juno solar array design, a summary of power estimates, an explanation of the modeling approach used by Aerospace, a detailed discussion of loss factors and performance predictions, a thermal analysis, and a review of risks to solar array performance

solar powered mission↗
NASA NTRS2007

Multijunction Solar Cells Optimized for the Mars Surface Solar Spectrum

This paper gives an update on the performance of the Mars Exploration Rovers (MER) which have been continually performing for more than 3 years beyond their original 90-day missions. The paper also gives the latest results on the optimization of a multijunction solar cell that is optimized to give more power on the surface of Mars.

solar power↗
NASA NTRS2005

Performance of High-Efficiency Advanced Triple-Junction Solar Panels for the LILT Mission Dawn

NASA's Discovery Mission Dawn is designed to (LILT) conditions. operate within the solar system's Asteroid belt, where the large distance from the sun creates a low-intensity, low-temperature (LILT) condition. To meet the mission power requirements under LlLT conditions, very high-efficiency multi-junction solar cells were selected to power the spacecraft to be built by Orbital Sciences Corporation (OSC) under contract with JPL. Emcore's InGaP/InGaAs/Ge advanced triple-junction (ATJ) solar cells, exhibiting an average air mass zero (AMO) efficiency of greater than 27.6% (one-sun, 28 C), were used to populate the solar panels [1]. The two solar array wings, to be built by Dutch Space, with 5 large- area panels each (total area of 36.4 sq. meters) are projected to produce between 10.3 kWe and 1.3 kWe of end-of life (EOL) power in the 1.0 to 3.0 AU range, respectively. The details of the solar panel design, testing and power analysis are presented.

triple junction solar cells↗
NASA NTRS1994

SIR-C/X-SAR Free Flyer Engineering Concept

After the Space Radar Laboratory (SRL)-1 and -2 missions, there is an opportunity to integrate the Spaceborne Imaging Radar (SIR-C/X-SAR) instrument with spacecraft bus systems for a 1988 launch.

SIR-C X-Band spaceborne Imaging Radar global mappi↗
NASA NTRS1992

Advanced photovoltaic solar array - Design and performance

This paper reports on the development of an ultralightweight flexible blanket, flatpack, foldout solar array design that can provide 3- to 4-fold improvement on specific power performance of current rigid panel arrays and a factor of two improvement over a first-generation flexible blanket array developed as a forerunner to the Space Station Freedom array. To date a prototype wing has been built with a projected specific power performance of about 138 W/kg at beginning-of-life (BOL) and 93 W/kg end-of-life (EOL) at 12 kW (BOL) for a 10-year geosynchronous (GEO) mission. The prototype wing hardware has been subjected to a series of system-level tests to demonstrate design feasibility. The design of the array is summarized. The major trade studies that led to the selection of the baseline design are discussed. Key system-level and component-level testing are described. Array-level performance projections are presented as a function of existing and advanced solar array component technology for various mission applications.

Kurland, Richard↗
NASA NTRS1991

Betavoltaics Of Increased Power

Batteries of newly developed betavoltaic cells proposed as long-lived sources of power of order of watts. High-power betavoltaic cell resembles solar photo voltaic cell, except it includes layer of beta-emitting material. Betavoltaic battery cells are stacked as in chemical battery, and surrounded by material containing beta rays. Intended for use aboard spacecraft, batteries also used in surgically implanted devices requiring high power.

Pool, Frederick S.↗
NASA NTRS1989

Advanced photovoltaic solar array development

Phase 2 of the Advanced Photovoltaic Solar Array (APSA) program, started in mid-1987, is currently in progress to fabricate prototype wing hardware that will lead to wing integration and testing in 1989. The design configuration and key details are reviewed. A status of prototype hardware fabricated to date is provided. Results from key component-level tests are discussed. Revised estimates of array-level performance as a function of solar cell device technology for geosynchronous missions are given.

Kurland, Richard M.↗
NASA NTRS1988

Status of Advanced Photovoltaic Solar Array program

The current development status of ultralightweight flexible-blanket foldout solar arrays being designed and fabricated under the NASA Advanced Photovoltaic Solar Array (APSA) program is surveyed. The goal of APSA is the construction of a 25-kW array with specific power 300 W/kg (BOL) by the year 2000. Topics discussed here include array configurations, blanket deployment systems, prototype wing-hardware fabrication, component-level test results, solar-cell technologies, and array performance estimates. Diagrams, drawings, graphs, and tables of numerical data are provided.

Kurland, Richard↗
NASA NTRS1987

Advanced photovoltaic solar array design assessment

The Advanced Photovoltaic Solar Array (APSA) program seeks to bring to flight readiness a solar array that effectively doubles the specific power of the Solar Array Flight Experiment/Solar Electric Propulsion (SAFE/SEP) design that was successfully demonstrated during the Shuttle 41-D mission. APSA is a critical intermediate milestone in the effort to demonstrate solar array technologies capable of 300 W/kg and 300 W/square m at beginning of life (BOL). It is not unreasonable to anticipate the development of solar array designs capable of 300 W/kg at BOL for operational power levels approx. greater than 25 kW sub e. It is also quite reasonable to expect that high performance solar arrays capable of providing at least 200 W/kg at end of life for most orbits now being considered by mission planners will be realized in the next decade.

Stella, Paul↗
NASA NTRS1987

Advanced photovoltaic solar array design

An ultralightweight flexible-blanket flatpack, foldout solar array design is defined. The design establishes a critical intermediate milestone of the NASA high-performance Advanced Photovoltaic Solar Array program through its primary objective of realistically demonstrating a solar array that can provide greater than 130 W/kg at beginning of life (BOL) and 100 W/kg at end of life for a 10-year geosynchronous 10-kW (BOL) space power system. This paper reviews the critical features of the preliminary design and the implications for long-term array technology development.

Kurland, Richard↗