Energy, water and carbon are inextricably linked. The limited endowments, uneven temporal and spatial distribution of energy and water resources pose great challenges to China's sustainable development. In this paper, a bottom-up model (China TIMES model) is developed to integrate China's energy system with water resources, to project water demand in power sector and to assess the impacts of China's Intended Nationally Determined Contributions (INDC) and water constraints on power generation portfolio out to the year 2050. The modelling results show that: (1) under reference scenario, electricity generation will increase from 4518 TW h in 2010 to 13,270 TW h in 2050, with CO2 emission from 3.1 Gt to 6.1 Gt and water withdrawal from 59 Gm(3) to 104 Gm(3); (2) CO2 mitigation target can help reduce water withdrawal in power sector by promoting the expansion of renewable technologies; (3) by affecting the cooling mixture, water cost has significant impact on water withdrawal in power sector; (4) when both CO2 and water constraints are considered, renewable technologies will be more prevalent. (C) 2015 Elsevier Ltd. All rights reserved.