Energetica India Magazine December 2020

compressors, discharge characteristic and power consumption of industrial fans (induced and forced draught), the pressure drop across pressure reduc- tion stations and control valve, will help in identifying operational efficiency of equipment and steam cycle compo- nents. The individual thermal power plant units are designed for a specific heat rate (kCal/kWh), it is essential to run the unit close to its design heat rate. One of the vital methods to monitor the key perfor- mance parameters is by simulation tool. The simulation of the heat balance ther - modynamic cycle model can be used to calculate the operating parameters at various stages of the power plant. The operating parameters obtained through simulation results indicate the plant con- dition concerning the original design. A comparison of calculated values and measured values will allow a deeper un- derstanding and depending on the qual- ity of the model used, it will allow identi- fying problems either in the cycle or in individual components. It is also possi- ble to verify individual measurements or readings from the station instruments with simulation model values. To achieve this, energy performance mapping of each plant using a simula- tion tool must have an effective perfor- mance monitoring of various parameters for operations. Monitoring should be in real-time and the key controllable param - eters must provide more timely and rapid feedback for effective decision making. The performance of the controllable pa - rameters not only helps in optimizing the power plant but also provides sensitive information on the technical condition of the power station. Some examples of monitoring such key parameters are cyl- inder efficiencies, turbine backpressure, cooling water flow, re-heater tempera - tures which will determine the optimum heat rate of the plant. An even more sophisticated approach is to validate the existing set of data col - lected by the distributed control systems (DCS) of the thermal power plant. Data validation is a mathematical method to correct the measured values in a way that the full set of measured values ful- fills all conservation laws like mass bal - ances, energy balances, performance balances, or phase equilibrium. This comparison of measured values through station instruments and the calculated values through simulation can be used for calibration of station instruments and helps the quality of measurements. In the present scenario, due to the inte- gration of Solar PV on large scale to the grid, thermal power plants are forced to run at part load. It is also important to understand that thermal power plant operations at part load operates close to its design performance parameters at partial loads using simulation. This can be done by using simulation tools for optimum operation and compares with actual measurements. It is essen- tial to utilize such tools to monitor the performance continuously with reliable data. This process helps in the identifi - cation of “hot spots” (causes for higher heat rate) in the operation of the power plant and downsizing existing higher capacity equipment with appropriate re- quirements in part load condition as this would be a more attractive and practical solution in terms of auxiliary optimisation and terms of profitability. In conclusion, thermal power plants are heavily affected by downward revisions in electricity demand, and its use in in- dustry is tempered by lower economic activity. Coal phase-out policies, the rise of renewables, and competition from nat - ural gas lead to part-load operating and the retirement of 275 gigawatts (GW) of coal-fired capacity worldwide by 2025 (13% of the total). To limit global warming to 1.5°C above pre-industrial levels, the world would need to transform in several complex and connected ways. The ev - er-growing cost of fuel reduction in heat rate and auxiliary power consumption of existing power plants will lead to better resource utilization and reduced emis- sions. POWER SECTOR 31 energetica INDIA- December_2020