A combined hydropower Plant integrates hydroelectric and steam power for enhanced efficiency, ensuring a consistent output at economical costs. The hydro component, particularly in facilities with ample storage, seeks to replace thermal power with available hydropower to reduce costs at the steam plant. Operational flexibility relies on water supply, storage, and load curve dynamics.
Throughout the year, these combined hydro and steam plants adjust to base or peak loads based on water availability. Challenges emerge in multipurpose hydro projects with constraints like flood management. Daily runoff patterns, affected by factors such as evaporation, add complexity to planning.
The combined operation aims to meet power demands by optimizing efficiency through effective hydro plant operation, head regulation, and spillage control. Achieving a balance between improving water head and limiting spillage is crucial, especially in scenarios with high storage development and downstream considerations, where minimizing spillage conflicts with maximizing water head for efficient power generation.
What are the Advantages of a Combined Hydroelectric Plant?
The benefits of a combined hydroelectric plant include the following:
- Enhanced Reliability: Collaboration between several power plants improves reliability in fulfilling consumer demand.
- Station Resilience: Other stations can continue providing consumers in case of failure, avoiding a complete shutdown.
- Cost-effectiveness: Interconnected systems offer cost-effective benefits by lowering energy costs per unit, requiring less initial investment, and reducing monitoring, operation, and maintenance expenses.
- Efficient Transmission: Using greater voltage levels on transmission lines improves system efficiency.
- Decreased Spinning Reserve Requirement: Interconnected systems lower the need for spinning reserves (backup energy generation capacity). After being brought online, the spinning reserve must run constantly for at least two hours.
Also See: What is Conventional Hydroelectric Plant?
What is Load Division between Power Stations?
Load division uses a load duration curve to show the downward variations of a certain load. The resulting curve aligns the highest load to the left and the lowest load to the right along the time axis, indicating how long each load lasts during the day.
When the load curve has a noticeably high peak value, it is usual to distribute the load across two or more interconnected power plants. The total load is then separated into two distinct parts:
- Base Load: This section is supplied by a single power station, ensuring a stable and uninterrupted power supply.
- Peak Load: The other power station is in charge of handling peak load, which occurs during periods of increased energy demand.
Which Types of Plants in Combined Hydroelectric Plant Requirements?
A combined hydroelectric power facility consists of a hydroelectric plant and a steam power plant. Hydroelectric plants excel at quickly handling loads and adapting to peak fluctuations, outperforming thermal facilities in this aspect.
- During periods of sufficient runoff, notably during the monsoon season, the hydro plant acts as a base load plant, while the thermal plant acts as a peak load plant.
- In contrast, during droughts, the thermal plant serves as the base load plant, while the hydro plant serves as the peak load plant.
These strategic designs allow for the efficient use of both types of plants based on prevailing conditions.
Recommended: What is Run-of-River Hydroelectric Plant?
