Industrial processes release substantial quantities of waste heat, which can be harvested to generate electricity. At present, the conversion of low grade waste heat to electricity relies solely on thermoelectric materials, but such materials are expensive and have low thermodynamic efficiencies. Although thermomagnetic materials may offer a promising alternative, their performance remains to be evaluated, thereby hindering their real-world application. Here we evaluate the efficiency and cost effectiveness of thermomagnetic materials that can be used in motors, oscillators and generators for converting waste heat to electricity. Our analysis reveals that up to temperature differences of several 10 K the best thermomagnetic materials outperform thermoelectric materials. Importantly, we find that the price per watt for some thermomagnetic materials are much lower compared to present-day thermoelectrics and can become competitive with conventional power plants. The materials library that we present here enables the selection of the best available thermomagnetic materials for harvesting waste heat and gives guidelines for their future development.

中文翻译：

---

用于收集低品位废热的高效且经济实惠的热磁材料

工业过程会释放大量废热，这些废热可用于发电。目前，将低品位废热转化为电能仅依赖于热电材料，但此类材料价格昂贵且热力学效率低。尽管热磁材料可能是一种很有前景的替代品，但它们的性能仍有待评估，从而阻碍了它们的实际应用。在这里，我们评估了热磁材料的效率和成本效益，这些材料可用于电机、振荡器和发电机，将废热转化为电能。我们的分析表明，在高达 10 K 的温差下，最好的热磁材料的性能优于热电材料。重要的，我们发现，与当今的热电材料相比，某些热磁材料的每瓦价格要低得多，并且可以与传统发电厂竞争。我们在此提供的材料库可以选择用于收集废热的最佳可用热磁材料，并为其未来发展提供指导。