SBIR-STTR Award

Thermoacoustic Radioisotope Generator (TRG)
Award last edited on: 5/1/2018

Sponsored Program
SBIR
Awarding Agency
NASA : GRC
Total Award Amount
$874,261
Award Phase
2
Solicitation Topic Code
S3.01
Principal Investigator
Geoffrey A Bruder

Company Information

Nirvana Energy System Inc

3130 Alpine Road Suite 288 Pmb 6
Portola Valley, CA 94028
   (216) 898-9990
   tammy.miller@nirvana-es.com
   www.nirvana-es.com
Location: Multiple
Congr. District: 16
County: San Mateo

Phase I

Contract Number: ----------
Start Date: ----    Completed: ----
Phase I year
2016
Phase I Amount
$124,975
The primary goal of the proposed project is to develop a thermal-to-electrical power conversion system that achieves 200-300 W of net electrical output, has >28% efficiency, and durability for life greater than 10 years in response to the S3.01 call of the NASA SBIRs. Due to the significant manufacturing and assemble cost reductions afforded by the TAPS architecture over traditional FPS systems, the TAPS solution could be used as a direct replacement over traditional thermoelectric or other Stirling based systems in space missions. Furthermore, the TAPS technology enables architectures that are difficult, or impossible with other systems. Specifically, TAPS can easily be utilized for a combined power and cooling duplex, and some preliminary designs have been created. Such systems would enable a sustained presence in extreme planetary environments such as the surface of Venus.

Potential NON-NASA Commercial Applications:
(Limit 1500 characters, approximately 150 words) Nirvana Energy Systems is currently working to commercialize the NASA technology through an exclusive patent license granted for the Alpha-STREAM technology that the TAPS technology is partially based on. The NES TAPS technology could be easily adapted to home use where high efficiencies are possible and the unit would function as a micro-Combined Heating and Power system. In an installation such as this the TAPS unit could be natural gas fed where to achieve overall high system efficiencies the unit would utilize excess heat to provide heated water for potable needs or for hydroponic heating. Excess electrical energy production would be sent to the grid. Similar to application for home power generation, other applications include commercial businesses, military uses (vehicles and domesticated areas), and the transportation industry. In particular, these industries desire higher electrical outputs but the validity of the TAPS architecture afforded by this Phase I effort would offer strong evidence in the scale-ability of the technology. Moreover, the reverse cycle of the TAPS system could be used for cooling in many cases, including as a refrigerant free domestic cooling system.

Technology Taxonomy Mapping:
(NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.) Actuators & Motors Conversion Generation Heat Exchange Lifetime Testing Machines/Mechanical Subsystems Models & Simulations (see also Testing & Evaluation) Prototyping Simulation & Modeling Tribology

Phase II

Contract Number: ----------
Start Date: ----    Completed: ----
Phase II year
2017
Phase II Amount
$749,286
Nirvana Energy Systems (NES) has pioneered and is commercializing an innovative ThermoAcoustic Power Stick (TAPS) partially based on technology developed by Xerox Palo Alto Research Center (PARC) and NASA. NES has demonstrated and is building a 1kWe TAPS for use in remote power applications where reliability for 20+ years is of paramount importance. The novel TAPS technology has no hot moving parts and incorporates well proven, reliable linear motors and alternators in an engine based on the Stirling cycle. NES has designed, optimized, built and tested all sub-systems for reliability, ease of manufacturing and cost reduction over currently available Stirling engines. The 1kWe TAPS formed the starting design for scaling down to a ~300 W tunable power thermoacoustic device. The system is insensitive to radioisotope heat degradation, capable of 10+ years continuous operation, inexpensive to manufacture using well established methods, and yields greater than 25% thermal to electrical efficiency all while being designed for a specific power greater than 30 W/kg. The NES Thermoacoustic Radioisotope Generator (TRG) represents the ultimate in remote power devices and is the next step toward reliable dynamic power conversion for space.The technical objectives of the NES TRG Phase II effort are to produce a prototype TRG convertor, build a test cell, and validate the designed system performance with a minimum of 500 hours of steady state operation.During this 18 month effort, the TRG design will undergo any final modifications based on NASA review. Test support hardware will be selected and designed. The prototype and test cell will be manufactured to exact specifications. A risk assessment will be conducted for the convertor. Subsystem and materials coupon tests will be conducted. The TRG system will be assembled and tested for a minimum of 500 hours.