12th International Symposium on District Heating and Cooling

The <strong>12th</strong> <strong>International</strong> <strong>Symposium</strong> on District Heating and Cooling,September 5 th to September 7 th , 2010, Tallinn, Estoniato implement the schemes, the performance data forthe commercial products, operation efficiency in fulland part load condition, has been extensivelyinvestigated and the database has been realized on thesimulation program.One can consider a variety of CHP systemconfigurations with various CHP prime movers andtypes of cooling chillers. If the type of CHP primemovers is being selected, the capacity of it is to bedetermined in the form of any percentage on the basisof the maximum value of annual hourly electricitydemand. Then, the feasible options, which can matchthe condition entered by the user, are compiledaccording to the relevant algorithm as shown in Fig. 5.(a) Heating load(b) Electricity loadFig. 4. Prediction of annual hourly energy consumption forthe apartmentthe number of units, and the load factor in terms of unitcapacity. When an option is selected by the user asdescribed above, its corresponding technical data forCHP product will be linked automatically in thesubsequent operation simulation procedures. Thesettlement of the system configuration for the coolingsystem can also be performed in a similar manner byproviding the data for the ratio of being in charge ofturbo or absorption type chillers.2. Modelling of DHC system for networkingoperationIn contrast with small cogeneration or CES system, theDHC system is not authorized to sell the electricity tothe customer directly in Korea [6]. As a result, theoperation mode differs from that of cogeneration orCES system, i.e. the facilities are operating dependingon the heat loads, and CHP facilities stop operatingduring summer to reduce waste heat production.Instead, the hot water load during the summer seasonis usually supplied from incinerators nearby, or heatonly boilers (HOB). However, the operation schemes ofDHC system for stand-alone operation are bound to bemodified to some extent by networking operation withCHP system on-site and the appropriate modelling forsuch an effect of networking operation on DHC systemis a key element for a reliable prediction of theoperation behaviours due to thermal network operation.In this study, the changes of operation schemes andcorresponding variations for physical or mechanicalaspects on existing DHC system side have beenrealized by employing mathematical correlations for thesake of simplicity. The mathematical correlations forenergy productions as a function of energyconsumption are developed based on the annualoperation data of a branch of Korea District HeatingCorporation (KDHC). By applying a simple, but credibleempirical correlations instead of performing anadditional cycle simulation for the existing DHC system,the calculation load and the complexity from thestandpoint of simulation are considerably alleviated.The procedure to obtain the correlations for energyproduction in terms of energy consumption are givenas follows,Fig. 5. Parametric entry of option for CHP system productThe user is to select the most desirable one among thelist of options by referring to the technical specificationfor each option such as the unit capacity of the product,159The required data for the establishment of themathematical correlation is given by,– Annual, heat and electricity production and the salesper day according to the facilities of heat production(CHP, HOB, Incinerator)– Annual, fuel consumption per day according to thefacilities of heat production (CHP, HOB)