Energy technology innovation plays a crucial role in reducing carbon emissions. This paper investigates whether there is relationship between energy technology patents and CO2 emissions of 30 provinces in mainland China during 1997–2008. Gross domestic product (GDP) is included in the study due to its impact on CO2 emissions and energy technology innovation, thus avoiding the problem of omitted variable bias. Furthermore, we investigate three cross‐regional groups, namely eastern, central and western China. The results show that domestic patents for fossil‐fueled technologies have no significant effect on CO2 emissions reduction; however, domestic patents for carbon‐free energy technologies appear to play an important role in reducing CO2 emissions, which is significant in eastern China, but is not significant in central, western and national level of China. The results of this study enrich energy technology innovation theories and provide some implications for energy technology policy making.
