What Is the Thermoelectric Generator (TEG) Figure of Merit (ZT) & Efficiency Calculator?
The dimensionless figure of merit ZT governs the thermal-to-electric power conversion efficiency of thermoelectric materials.
How Does the Thermoelectric Generator (TEG) Figure of Merit (ZT) & Efficiency Calculator Work?
Optimal materials combine high electrical conductivity (to reduce Joule heating) with low thermal conductivity (to preserve thermal gradients).
Thermoelectric Generator (TEG) Figure of Merit (ZT) & Efficiency Calculator Formula & Variables
The core mathematical equation utilized by this calculator is expressed as:
ZT = \frac{S^2 \sigma T_{\text{avg}}}{\kappa}, \quad \eta_{\max} = \frac{T_h - T_c}{T_h} \frac{\sqrt{1 + ZT} - 1}{\sqrt{1 + ZT} + T_c/T_h}
Thermoelectric figure of merit and maximum device conversion efficiency.
How to Use the Thermoelectric Generator (TEG) Figure of Merit (ZT) & Efficiency Calculator
- Input Seebeck coefficient S, electrical conductivity sigma, thermal conductivity kappa, and junction temperatures.
Step-by-Step Example Calculation
Bismuth Telluride Module
Input Values:
seebeckCoefficientVPerK:0.00022
electricalConductivitySPerM:110000
thermalConductivityWPerMK:1.4
hotSideTempK:600
coldSideTempK:300
Worked Steps: Predicts ZT = 1.711 at 450 K average temperature with TEG thermal efficiency of 10.96%.
Understanding Your Result
Outputs figure of merit ZT, power factor, Carnot limit, and maximum generator efficiency percentage.
Factors That Affect the Result
- Nanostructuring scatters phonons, reducing thermal conductivity kappa and boosting ZT.
When Should You Use This Calculator?
- Radioisotope thermoelectric generators (RTGs) in deep space probes and automotive exhaust waste heat harvesting.
Assumptions & Limitations
- Assumes temperature-averaged constant material properties.
Frequently Asked Questions
Calculation Accuracy & Reference Note
Standard formulation derived by Abram Ioffe in 1957.