What Is the Difference Between a Thermoelectric Cooler and a Thermoelectric Generator?

Thermoelectric devices use heat and electricity in opposite ways: some generate power from heat, others move heat using electricity. The two most common types are the Thermoelectric Cooler (TEC) and the Thermoelectric Generator (TEG). Though they rely on similar materials and principles, their functions and applications are very different.

How They Work

TEC (Thermoelectric Cooler): Uses the Peltier effect — when electric current passes through a thermoelectric module, one side gets cold while the other side gets hot. It’s used for cooling.

TEG (Thermoelectric Generator): Uses the Seebeck effect — when one side of a module is hot and the other is cool, it generates electricity. It’s used for power generation.

Key Differences at a Glance

Where They’re Used

TECs
Cooling CPUs, sensors, and lasers

Mini fridges and portable coolers

Medical and lab devices needing precise temperatures

TEGs
Automotive: Recovering engine heat to power electronics

Factories: Converting waste heat into electricity

Wearables: Powering small devices with body heat

Smart Homes: Running sensors without batteries

Spacecraft: Long-life power for NASA missions

Shared Materials and Design Nuances

Both TECs and TEGs often utilize similar semiconductor materials, like bismuth telluride (Bi₂Te₃), due to their favorable thermoelectric properties. However, the design and construction of these devices differ to suit their specific functions:​
TECs: Emphasize efficient heat transfer with minimal thermal stress, often incorporating smaller elements and materials optimized for rapid heat exchange.​
TEGs: Designed to endure significant temperature differences, requiring robust materials and larger elements to maximize voltage output and durability.

Conclusion

While Thermoelectric Coolers and Thermoelectric Generators are rooted in the same fundamental science, their divergent applications underscore the versatility of thermoelectric technology. TECs offer efficient, compact solutions for temperature control, whereas TEGs provide reliable power generation in challenging environments. As advancements continue in material science and thermoelectric efficiency, the potential applications for both devices are poised to expand, contributing to energy solutions across various industries