Energy consumption, environmental impact, and sustainability have risen fast through the ranks, achieving the first places in driving investments, policies, and concerns of all countries at any developmental stage. Energy transformation, though, must cope with nonunitary efficiency of devices and processes, which results in a distributed production of waste heat. A reduction of emissions, implying a conversion of waste heat to more noble forms of energy and a concurrent increase in efficiency of the same devices and processes, is of paramount importance. In view of the enthalpy content and distribution of the different sources of waste heat, low‐grade/low‐enthalpy sources below 200 °C are considered the most fertile field for research and development, with an impressive industrial growth rate. Thermodynamic cycles and thermal conversion devices based on the most relevant physical effects are herein introduced and briefly described, including both solutions that already achieved industrial maturity and less developed systems and devices whose study is still in progress. A specific focus on three application domains, selected due to their economic relevance, is done: industrial processes for the vast energy and capital availability, automotive sector for its permeation, and wearable devices for the market size. Limits and opportunities are critically discussed.

中文翻译：

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余热发电：技术，当前应用和未来潜力

能源消耗，环境影响和可持续性迅速晋升，在任何发展阶段推动所有国家投资，政策和关注的问题均位居第一。但是，能量转换必须解决设备和过程的单效率问题，这将导致废热的分布产生。减少排放，意味着将废热转化为更贵重的能源形式，同时提高相同设备和工艺的效率，至关重要。考虑到不同废热的焓含量和分布，低于200°C的低品位/低焓源被认为是研究和开发的最肥沃领域，工业增长率令人印象深刻。本文介绍并简要介绍了基于最相关物理效应的热力学循环和热转换设备，包括已经实现工业成熟的解决方案和尚待研究的欠发达的系统和设备。根据其经济意义选择了三个应用领域，它们的重点是：工业过程以获取大量的能源和资本，汽车行业以其渗透性为目标，而可穿戴设备则以市场规模为目标。极限和机会被严格讨论。根据它们的经济意义进行选择：完成工业过程以获取大量能源和资本，为汽车行业渗透，并为市场规模选择可穿戴设备。极限和机会被严格讨论。根据它们的经济意义进行选择：完成工业过程以获取大量能源和资本，为汽车行业渗透，并为市场规模选择可穿戴设备。极限和机会被严格讨论。