Cold Energy Storage Schemes And Economic Analysis Of An Office Building In Shenzhen

At present,the contradiction between power supply and demand is very prominent in China.One side,the power system is in overload operation for a long time during the daytime peak period,which has a great impact on the security and stability of the power system;the other side,the power consumption at night is very low.The ratio between peak-valley difference and peak load of power grid is 30%?40%.In order to reduce load peak and valley difference optimization the allocation of resources,it is of great practical significance to develop storage air-conditioning system.There are four basic types of cold storage media in cold storage air conditioning systems: water,ice,eutectic salt and gas hydrate.Due to the large heat capacity of water and the high latent heat of phase change of ice,and both of them are easy to obtain and cheap.Therefore,water and ice storage are the two most widely used cold storage systems in the engineering.This article takes an office building project which in Shenzhen city as the research object.De ST-c software was used for energy consumption simulation to calculate the dynamic air conditioning load of the target building throughout the year.The cooling load characteristics of the building and the load distribution of the whole cooling season were analyzed.As the research object has no air conditioning load from 20:00 p.m.to 7:00 p.m.It is suitable to use the cold storage air conditioning system.According to the local energy condition in Shenzhen and the scale of the research object,the conventional chiller system,ice storage air conditioning system and water storage air conditioning system were selected as the cold source schemes for analysis and comparison.Through detailed calculation,the main equipment and materials of air conditioning system in each scheme are selected.Compared with the conventional air conditioning system,the cold storage system needs to add the cold storage device,the cold storage water pump and the plate heat exchanger.According to the selection of the main equipment and materials of the research object,the initial investment,operation energy consumption and operation cost of each scheme air conditioning system are calculated.The initial investment and operation energy consumption of conventional chiller air conditioning system are the least,but the operation cost is the highest.The initial investment and operating cost of the equipment are only one aspect of economy.They do not consider the time value of the capital and the life of the equipment in its whole cycle.The dynamic annual cost method was adopted to comprehensively analyze and compare the economy of the air conditioning system in each scheme,and the optimal scheme of air-conditioning system is obtained.The annual cost is mainly affected by market interest rate and peak-valley tariff ratio.This article takes the market interest rate and peak-valley tariff ratio as the change factors,the sensitivity analysis was carried out on the annual cost value of the selected cold source scheme,and the influence degree of market interest rate and peak-valley tariff ratio on the annual cost value was obtained.Based on the equipment selection and economic analysis of air conditioning systems in various schemes,I hope that designers and owners can have a certain understanding of the design and economy in different schemes.,so that the storage air conditioning can be better applied and popularized in areas with power shortage.