Biscrolled CNT Yarns in Flywheel Grid Storage Devices

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Flywheel energy storage is a promising technology currently in the design and engineering phase.  For the technology to become comercially viable, the technology must use lower cost materials while delivering higher reliability.  Flywheel storage offers long-term promise in a future state where an increasingly largeer proportion of electricity is generated by renewable resources.  Renewables like wind and solar suffer from both predicatble and unpredictable intermittency, creating a need for both long-term load leveling or short term frequency regulation  by utilities.  Flywheel storage offers a solution to mitigating frequency variability because it can be spooled up and down quickly and can maintain very high efficiency over short periods of time (typically less than an hour).  This type of storage may allow the electricity grid to operate more efficiently when things like cloud cover or wind gusts create spontaneous load spikes or plunges.

Flywheel energy storage works by storing electrical energy as rotational energy in a flywheel suspended between vacuums in a near vacuum.  Electricity entering the flywheel energy storage system accelerates the flywheel to tens of thousands of RPMs.  The near frictionless flywheel spins until energy is needed and the system is decelerated.  The shear speeds and precision of these components requires the use of strong, light, and inexpensive components to ensure the systems can store and release energy in an efficient and reliable manner.  Scientists are researching, designing, and engineering novel materials to make flywheel storage a more viable and cost effective means of ushering a new clean and efficient energy economy.

Stanord and University of Texas scientists have designed new carbon materials for use in novel deign architectures for flywheel energy storage systems.  The researchers are impregnating biscrolled carbon nanotube yarns with aluminum and iron oxide nanoparticles.  Impregnating these CNT yarns with the aforementioned nanopraticles allows for the creation of extremely strong and flexible yarmns that have both magnetc and superconducting properties.  The researchers intend to use these new super yarns in flywheel components to reduce their weight and increase their strength.  The yarns will be used to create ultra-low loss bearings and motor generators to increase the efficiency of energy storage flywheels.  These components are necessary to electromagnetically levitate the flywheel rotors and increase the capacity and lifetime of the flywheels. These second generation energy flywheels will be much more reliable and efficient and will use material resources that are much more common and cost effective than those currnetly in use.

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The biscrolled CNT yarns will be incorporated into multiple components in the flywheel design to increase strength and durability thus increasing product life and reducing costs.




Benefit Summary: 

These novel materials have the potential to decrease the cost and environmental impact of energy storage, making renewable energy a baseload power source and more ubiquitous. Biscrolled CNTs have the potential to preserve environmental quality and improve resource efficiency.


Risk Summary: 

SWCNTs have the potential for the secondary release of hazardous materials into and in reaction with the human environment via the creation of hazardous waste in the recycling process. The recycling process for repurposing requires the use of acetone, deionized water, hydrochloric acid and nitric acid. Additionally, SWCNTs have potentially harmful pulmonary toxicology profiles similar to other Ultra-Fine Particles (UFP). Additionally, research is emerging that suggests SWCNTs produce mitochondrial DNA damage and increased cardiovascular plaque buildup in mice. This will likely drive more research into the effects of SWCNT exposure in SWCNT workplace environments.

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