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position on some types of renewable energy. For the development of renewable energy utilization, it is extremely important to take suitable utilization strategies according to local conditions. Six different strategies have recently been proposed for the European Union(EU) energy system in Energy Roadmap 2050.Recent studies in dicate that district heating plays an important role in the implementation of future sustainable energy systems [1]. However, to ease the pressure on biomass resources and investments in renewable energy, future sustainable energy systems must be applied. Thus,the concept of 4th Generation District Heating (4GDH) has been mentioned. Compared to the former three generations, 4GDH meets the challenge of more energy efficient buildings and is an integrated part of the operation of smart energy systems, i.e.integrated smart electricity, gas and thermal grids [2]. Therefore, Renewable energy and building integrated design has become a trend. The development experience of the world is worth for inspiring.