The Energy Consumption And Economic Analysis Of A District Cooling System

A district cooling project in Yantai is analyzed as an example of the issue. In summer,lithium bromide absorption chiller driven by steam which the temperature and pressure is reduced to refrigerate. And the chilled water was delivered to cooling users used existing heating network. Also the chilled water delivered maximum distance of 9.38 km which is the furthermost in domestic.In the face of energy consumption,A calculation methods of district cooling system in this paper was introduced.Then the measured data of the district cooling project is substituted into the calculation model to get the energy consumption of the projects throughout the cooling season. And in order to compare the energy consumption of district cooling,this paper introduced energy consumption method of independent refrigeration that user-created cooling source and obtained cooling power consumption using existing data of independent refrigeration. For comparison purposes,the power consumption and heat consumption are equivalent to standard coal consumption. The district cooling project was not energy-efficient by comparing both of the cooling methods. Because of the bad pipe insulation that caused large cold loss. Only by improving pipe insulation performance,minimize cold loss,energy-efficient of district cooling will be higher than cooling method of self-built cold source.About cooling face, this paper put forward the calculation method of cooling losses and select the first station to the most remote users as the worst loop to calculate cooling loss and temperature rising of the chilled water. Then the calculation results were compared with the measured data to verify the accuracy of the calculation method. We can see that the project has great cooling loss due to the thermal conductivity of pipe insulation layer is too large which resulting in the insulation effect is not good.Then this article analyzed the impact of cooling loss factors,and with the existing pipeline unchanged,the smaller the coefficient of thermal insulation,the greater the temperature difference between supply and return water,the less cooling loss. Moreover,in the case of long-distance transport of chilled water,the cooling loss of chilled water caused by the heat exchanging with the outside world is greater than that of causing by chilled water pump.In the view of economic, the paper proposes a method of economic analysis of district cooling. In the user’s perspective,the paper compared the economic benefits of self-built refrigeration room and district cooling using annual cost. It can be seen that district cooling method has a better economic benefit than the method of economic selfbuilt cold source for users. And in the perspective of cooling business,financial evaluation of the project was made,which got the results of the project profitability were good Then the sensitivity analysis was made to obtain the factors that influence the economic efficiency of enterprises. And by the economic analysis of users and the enterprise,the reasonable price range of cooling was got.