Bottom-up analysis of industrial waste heat potential in Taiwan

Industrial manufacturing significantly contributes to energy consumption and carbon dioxide emissions throughout the world. Global warming and its associated changes in the world climate pattern are accepted worldwide as the gravest threat to humanity. To mitigate the impacts of global warming and to solve future energy demands, industrial waste heat is regarded as a possible answer. In this paper, a bottom-up approach is presented to estimate the theoretical and technical waste heat potentials. More than 11,000 data sets of boilers from different industries were evaluated, and the results show that the theoretical (temperature≥35 °C) and technical (temperature≥150 °C) industrial waste heat potentials can be up to 89.66 PJ/y and 6.92 PJ/y, or 17.3% and 1.3% of the total industrial heat energy use in Taiwan, respectively. The majority of the waste heat potential (61.8%) is in the 100–150 °C temperature range, 25.4% is in the range of 150–200 °C, and 11.0% is above 200 °C. Industrial waste heat (IWH) can be converted into electricity through heat conversion technologies. Organic Rankine cycle (ORC) has been recognized as a well-known and promising solution to recover IWH, and the theoretical and technical power generated for this technology were identified as 311,249 and 24,022 MW, respectively.