Opened in 1985 on the Songhua River side of Wangjiang Hotel, construction area of ​​15,000 square meters, was the tallest building in Harbin. However, before 2003, Wangjiang Hotel was very embarrassed. Winter heating, with coal-fired boilers, summer cooling, with central air conditioning. There are all day to supply hot water, there are only a dozen boiler burning stove, the hotel throughout the year with coal up to more than 3,000 tons, operating costs are about 120,000 yuan, in addition to smoke, slag discharge environmental pollution fees Wait. Pollution caused by burning coal, so that residents in the neighborhood unbearable, frequently sued the relevant departments Wangjiang Hotel, the environmental protection department also always fine. Overwhelmed Wangjiang Hotel, happened to encounter Professor Sun Dexing School of Harbin Institute of Technology. The hotel will be developed by Professor Sun Dexing urban primary sewage heat pump installed in the air-conditioned room, saving an area of ​​over 100 square meters, the use of new equipment, new energy sources, the hotel's annual energy operating costs dropped from 1.1 million yuan per year to 55 Million or so. In just two years, the initial cost of the investment has already been saved back. More importantly, the hotel started to have more than 100 million yuan profit each year, and this is precisely the part saved in saving energy. Today, the boiler was demolished, the boiler room converted into a garage and staff quarters, the coal pile disappeared, the beautiful brick covered, the surrounding environment has become clean. 150 meters away from the hotel under the Ho-Run Street, a city's original sewage trunk, became the hotel's main source of power.