A dual-stage sodium thermal electrochemical converter (Na-TEC)

Limia, Alexander; Ha, Jong Min; Kottke, Peter A.; Gunawan, Andrey; Fedorov, Andrei G.; Lee, Seung Woo; Yee, Shannon K.

doi:10.1016/j.jpowsour.2017.10.022

Cited by 20 publications

(23 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The values for electrical power output P , which is a function of current density, the total area of solid electrolytes, and voltage output, is taken from our thermodynamic modeling work on the dual‐stage Na‐TEC and the results of thermal modeling of the prototype modules. [ 7,9 ] The total cost of the device C is divided into volumetric costs and areal costs,

C = \sum_{i} {(C^{'''} V)}_{i} + \sum_{k} {(C^{''} A)}_{k}

where the first term (denoted by V ) represents the sum of the volumetric costs, and the second term (denoted by A ) represents the sum of the areal costs.…”

Section: Methodsmentioning

confidence: 99%

“…[ 5 ] In addition to being carbon‐neutral, the principle difference between solid‐state energy conversion and turbomachinery is the lack of moving parts, which can strongly impact the system lifespan and maintenance requirements, and by extension, the levelized cost of electricity (LCOE). A sodium thermal electrochemical converter (Na‐TEC), which is a special variant of an alkali metal thermal‐electric converter, [ 6 ] can theoretically achieve thermodynamic conversion efficiencies above 45% and rejects heat at a sufficiently high temperature (≈550 K), [ 7 ] making it amenable to mCHP applications. [ 8 ]…”

Section: Introductionmentioning

confidence: 99%

“…The isothermal ion expansion process, where heat is directly converted to work, is responsible for the high ideal efficiency of this cycle. In one of our separate publications, [ 7 ] we reviewed the technical operation of this conventional single‐stage Na‐TEC and revisited the equations that describe it in more detail. We also reviewed and discussed the key factors and challenges that affect the performance of single‐stage Na‐TEC.…”

Section: Introductionmentioning

confidence: 99%

“…More recently we showed that a multistage Na‐TEC can achieve a high practical conversion efficiency by lowering the average device temperature, which in turn reduces the parasitic heat losses. [ 7,9 ] The radial dual‐stage Na‐TEC design has the potential to achieve a high practical thermal efficiency (up to 29%), which exceeds the efficiency of previously developed single‐stage devices (up to 19%). [ 10 ]…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

A Cost‐Performance Analysis of a Sodium Heat Engine for Distributed Concentrating Solar Power

Gunawan

Singh

Simmons

et al. 2020

Advanced Sustainable Systems

Self Cite

View full text Add to dashboard Cite

also an option. [3] Instead of burning fuels, concentrating solar power (CSP) [4] can be used to deliver the heat and power in such systems, enabling a carbon-neutral mCHP system. Furthermore, the use of solid-state technologies, such as Na-TEC, to convert energy from CSP exhibits key advantages over the more mature and economically viable turbomachinery used in current CSP systems. [5] In addition to being carbonneutral, the principle difference between solid-state energy conversion and turbomachinery is the lack of moving parts, which can strongly impact the system lifespan and maintenance requirements, and by extension, the levelized cost of electricity (LCOE). A sodium thermal electrochemical converter (Na-TEC), which is a special variant of an alkali metal thermal-electric converter, [6] can theoretically achieve thermodynamic conversion efficiencies above 45% and rejects heat at a sufficiently high temperature (≈550 K), [7] making it amenable to mCHP applications. [8] Na-TECs convert heat directly into electricity, without moving parts, via the isothermal expansion of Na ions through a beta″-alumina solid-electrolyte (BASE). [6] In the Na-TEC, heat vaporizes Na near ambient pressure in an evaporator. A thermally generated pressure difference drives Na ions through the converter. At the triple phase boundary of Na-anode-BASE, the Na atoms ionize (Na → Na + + e − ) and the electrons simultaneously traverse an external load. A thermally generated pressure difference drives Na ions through the converter. The electrons and ions then recombine on the cathode-BASE interface and the Na atoms return to the vapor phase at lower pressure. This low pressure Na vapor is then cooled and condensed to the liquid phase in a condenser and a wick passively returns the liquid Na to the evaporator. The isothermal ion expansion process, where heat is directly converted to work, is responsible for the high ideal efficiency of this cycle. In one of our separate publications, [7] we reviewed the technical operation of this conventional single-stage Na-TEC and revisited the equations that describe it in more detail. We also reviewed and discussed the key factors and challenges that affect the performance of singlestage Na-TEC. More recently we showed that a multistage Na-TEC can achieve a high practical conversion efficiency by lowering the average device temperature, which in turn reduces A sodium thermal electrochemical converter (Na-TEC) generates electricity directly from heat through isothermal expansion of sodium ions across a beta″-alumina solid-electrolyte. This heat engine has been considered for use with conventional concentrating solar power (CSP) systems before. However, unlike previous single-stage devices, the improved design uses two stages with an interstage reheat, allowing more economical and efficient conversion up to 29% at a hot side temperature of 850 °C. Herein, a cost-performance analysis for this improved design assesses opportunities for distributed-CSP in the context of micro-combined heat and power syste...

show abstract

C = \sum_{i} {(C^{'''} V)}_{i} + \sum_{k} {(C^{''} A)}_{k}

where the first term (denoted by V ) represents the sum of the volumetric costs, and the second term (denoted by A ) represents the sum of the areal costs.…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

A Cost‐Performance Analysis of a Sodium Heat Engine for Distributed Concentrating Solar Power

Gunawan

Singh

Simmons

et al. 2020

Advanced Sustainable Systems

Self Cite

View full text Add to dashboard Cite

show abstract

“…The neutral sodium releases heat and then condensates to the liquid phase. The liquid sodium is returned to the evaporator region by a porous capillary wick system [44,45]. Taking into account the power output and the heat input, see Fig.…”

Section: The Efficiency Of a Sodium Thermal Electrochemical Cellmentioning

confidence: 99%

Solar-driven sodium thermal electrochemical converter coupled to a Brayton heat engine: Parametric optimization

Peng

González-Ayala

et al. 2021

Renewable Energy

View full text Add to dashboard Cite

A novel high-efficiency device comprised of three subsystems, a solar collector, a sodium thermal electrochemical converter, and a non-recuperative Brayton heat engine, is modeled by taking into account the main internal and external irreversibility sources. The model extends previous works in which the heat waste of the electrochemical converter is used as heat input in a Brayton gas turbine to study its performance and feasibility when a solar energy input is added. The operative working temperatures of three subsystems are determined by energy balance equations. The dependence of the efficiency and power output of the overall system on the solar concentration ratio, the current density, the thickness of the electrolyte, and the adiabatic pressure ratio (or temperature ratio) of the Brayton cycle is discussed in detail. The maximum efficiencies and power output densities are calculated and the states of the maximum efficiency-power density are determined under different given solar concentration ratios. The parametric optimum selection criteria of a number of critical parameters of the overall system are provided and the matching problems of the three subsystems are properly addressed. It is found that under a solar concentration around 1350, the maximum efficiency and power output density of the proposed hybrid system can reach, respectively, 29.6% and 1:23 Â 10 5 W/m 2. These values amount approximately 32.7% and 156% compared to those of the solar-driven sodium thermal electrochemical converter system without the bottoming Brayton cycle. The Pareto front obtained from numerical multiobjective and multi-parametric methods endorses previous findings.

show abstract

Future options of electricity generation for sustainable development: Trends and prospects

Rashid

Joardder

2022

Engineering Reports

View full text Add to dashboard Cite

Electricity is an important part of our daily life. It is mainly generated from conventional energy sources. Conventional energy sources are diminishing day by day; whereas, energy demand increases significantly. Moreover, less land availability, low budget for energy, and weather‐dependent renewable sources result in poor energy management all over the world. Therefore, proper management of conventional energy and simultaneous finding of potential alternative energy sources are the prime concerns of energy‐related researchers. In this article, literature relating to less‐implemented energy sources is reviewed to demonstrate their current status and future prospects. This review shows that along with current renewable and conventional sources of energy, these less‐implemented energy sources can contribute substantially to overcome the energy scarcity in electricity production. Proper planning and improvement are required to get sufficient benefits from these less‐implement energy sources. In order to clarify the electricity generation from less‐applied energy sources, many figures are adapted using the concept and information of reviewed literature. In those figures and related text, several possible ways of electricity generation using these energy sources and their potential implementation techniques with related challenges have been outlined. The electricity generation rate and their corresponding applications are also depicted. Proper steps to popularize these less‐focused sources of energy would mitigate high energy demand all over the world and offers a cleaner environment for livelihood.

show abstract

A dual-stage sodium thermal electrochemical converter (Na-TEC)

Cited by 20 publications

References 20 publications

A Cost‐Performance Analysis of a Sodium Heat Engine for Distributed Concentrating Solar Power

A Cost‐Performance Analysis of a Sodium Heat Engine for Distributed Concentrating Solar Power

Solar-driven sodium thermal electrochemical converter coupled to a Brayton heat engine: Parametric optimization

Future options of electricity generation for sustainable development: Trends and prospects

Contact Info

Product

Resources

About