As with everyone else, the bottom line for countries is to save money, and one way of doing that is by saving energy. An example is China, which has announced that it will invest 1.5 trillion yuan (US$193 thousand million) by making existing buildings more energy efficient by 2020 so as to save millions of tonnes of coal. Warning that wasted energy was slowing economic growth, the Vice-Minister of Construction, Qiu Baoxing, said 350 million tonnes of coal could be saved in 15 years if existing buildings were renovated to make them more efficient, and if new buildings met green standards.