Overview of interconnected grid system management using old power plants
- 1. "OVERVIEW OF INTERCONNECTED GRID MANAGEMENT SYSTEM USING OLD POWER PLANT" GROUP 1. Bari, Md. Shafiul -11-20010-3 2. Hossain Maruf -11-20056-3 3. Khayum Md.Omar -11-19061-2 Supervisor: Rethwan Faiz Assistant Professor American International University Bangladesh
- 2. WHY WE CHOSE THIS TOPIC • By this thesis, we can reduce load demand on national grid. • This system is cheaper than hiring quick rental power plants. • As using diesel used power generation is more costly, we chose natural gas as fuel. • If we interconnect these plants, the system won’t be reliable on limited amount of plants.
- 3. CORE CONCEPT • The main objective of our thesis was to cover the peak load demand by using the commissioning based power plants. • We used the old commissioned power plants only for handling the peak loads, not for the base loads. • We collected all power plants data in Bangladesh. • We choose Gulshan-1 as the targeted area in Dhaka & collected the necessary power data for this area. • We created load curves from the collected data. • We chose appropriate power plants which were commissioned decades ago(Ashuganj unit-3, unit-4, unit-5). • We designed a system that shares the load this area generates between the old plants. • At last, we ran the system simulation in HOMER.
- 5. TRANSFORMER FOR GULSHAN - 1
- 7. DATA ANALYSIS We collected data about all power plants that are available in our country including new and old power plants. We chose the Gulshan-1 area as our targeted zone. The power generation chart that was collected from PDB annual reports in 2015 is given in the next slide.
- 9. PLANT SELECTION For our system, we chose 3 power plant units. They are: Ashuganj unit-3, unit-4 & unit-5. All of these plants were commissioned in the late eighties. As they have suffered mostly in terms of derated capacities, we chose them as the worst case scenario.
- 10. LOCATION SELECTION As we have stated before, we chose Gulshan-1 area as our intended area. This zone is supplied power by the Ullon Power Substation in west Rampura. It is supplied a 132 KV source line. We visited this substation and recorded logbook data for this area. All data are taken in hourly, weekly, monthly & half- yearly basis. Load chart and graphs are given in the later slides.
- 11. HOURLY LOAD The hourly read was taken from 6 July, 2015 (Week 28). The data was taken at 1 hour interval from 12 AM to 11 PM. As we will see from the graph, 2:00 PM noon is the time, when the highest load is 72.7MW. The chart and graph is given in the next slide.
- 13. LOAD CURVE
- 14. WEEKLY LOAD The weekly load was taken from 29 June, 2015 to 5 July, 2015 (Week 27). The data chart and graph are given next.
- 16. LOAD CURVE
- 17. MONTHLY LOAD The monthly read was taken from June 2015 (Week 23-27). As June is the summer month in Bangladesh, moreover in the middle of the year, it was chosen as base line. As per chart we will see, 62.3 MW is the highest load. The chart and load graph are given next.
- 19. LOAD CURVE
- 20. HALF-YEARLY LOAD The half-yearly data is taken from the first half of 2015. All data are converted into load curves. The chart and graph are given next.
- 22. LOAD CURVE
- 24. SIMULATION RESULTS For this simulation, we used HOMER Micro power Optimization Tool to simulate proposed grid and witnessed the desired power generation, load coverage and consumption costs.
- 25. ON/OFF SCHEDULE When considering the Ashuganj units, we devised a yearly schedule assuming seasonal demand changes. The forced on/off state will be used to maintain this schedule. In other times, optimized state will be used.
- 26. SCHEDULE GRAPH
- 27. UNIT EFFICIENCY Ashuganj power plant units uses natural gas as fuel for power generation. The output efficiency is shown in the next graph.
- 28. EFFICIENCY GRAPH
- 29. UNIT COST Ashuganj chosen Units have a derated capacity spanning from 16 MW to 40 MW. To maintain stable power generation, a cost curve covering capital and replacement costs are given next.
- 30. COST CURVE
- 31. NET PERCENTAGE COST The net profit percentage is the ratio of after- tax profits to net sales. It reveals the remaining profit after all costs of production, administration, and financing have been deducted from sales. As we will see later in the graph, all 3 units generated net percentage costs, while one unit actually handled the 4 billion dollar yearly cost while the other two could not.
- 32. CASH FLOW SUMMARY Here is a cash flow summery for all 3 units as a net present cost. It shows net percent curve for the units. Costs were taken in USD ($) value. Overall cost will be shown later in the slides.
- 34. TOTAL SYSTEM COST Here, every unit corresponds to the system in accordance with capital, replacement, operating/maintenance and fuel cost as well as salvage cost. The system result total in positive value indicates economical viability of this project.
- 35. TOTAL SYSTEM COST CHART
- 36. NATIONAL CASH FLOW National cash flow is the incoming and outgoing of cash in this system. In our thesis, we derived the yearly chart for nationwide cash flow. Here, we will see the demographic chart for the national cash flow for our designated operating system. Here, the amount of capital and replacement ultimately overshadows the overall replacement costs. The capital shows negative at start because of lack of financial data from Siddirganj power plant.
- 37. YEARLY CASH FLOW GRAPH
- 38. MONTHLY AVERAGE ELECTRICITY PRODUCTION In the next slide, we will see a graph that shows us the monthly average power generation with three different color opacity denoting three different units.
- 39. PRODUCTION CHART
- 40. FUTURE POWER GENERATION We will see a plot charted by the overall peak power generated per every decade. According to the graph, we will see that is it is gradually declining.
- 41. LONG TERM GENERATION In the next graph, we will see the future power generation of this system as for 7 years, it will be capable of handling load demands; therefore approving our prediction that this system can serve us for 7-8 years. Given that these are old power plants, so long term durability is not an option. Power plot is an graphical analysis of power generation over on a timely basis. The power plot shows peak power generation by this system declining over the years.
- 42. POWER PLOT
- 43. ADVANTAGES • The peak load of the power stations can be exchanged. The excess load can be shared by other power stations interconnected with each another if the load of a power station shows a peak demand which is greater than the rated capacity of the plant. • This system gives a direct key to use the obsolete power plants. • This system is quite economical for some of concerned power stations. • In interconnected grid system, this system can be more efficient because here almost all the power plants are connected in parallel so almost all of them are connected so there is more chances for the higher efficiencies than other systems.
- 44. DISADVANTAGES • As stated before, Gulshan-1 area power is provided by Siddirganj power plant relayed through Rampura Substation which acts as the main plant in this thesis. As we couldn’t collect data from Siddirganj plant, we couldn’t compare simulation results with them. Therefore, this thesis partially relies on the type of plant which will serve as the basis. • If any major breakdown happens it can create big problem to overall system and sometime it can damage other power stations also if any major fault happens. • As almost all the power plants are connected in parallel so there is not much standby unit or power plants for emergency so it can be a dangerous in emergency situations. • The interconnected grid system also requires some extra care, because it’s a huge system and huge parts to control or if anything ever happens accidently at any point it will affect the whole system and grid and as well as to the power plants.
- 45. FUTURE IMPROVEMENTS • As this system is designed with derated power plants, stabilizing long term reliability(In years) in the future will benefit the system. • In the future, additional features to handle unprecedented load spikes will improve the system. • If we can maintain these power plants with peak maintenance for a long time, costs can be reduced even more in the future. • In the future, researchers can integrate smart grid system in our thesis to better utilize the old power plants. • Using virtual power networks in our system will automate the entire system.
- 46. SPECIAL THANKS We would like to express our special gratitude to our honorable Asst. Professor Rethwan faiz Sir.