The Challenges of Thermal Power Generation in the age of Renewable Energy

In the coming years, the power generation industry is expected to face daunting challenges to meet the global energy demand. By 2030, the use of electricity is expected to double across the world and go up by three times in developing countries. The demand and pressing need for alternate sources of energy have never been greater. One of the biggest obstacles to making this switch is the maintenance of complex power plant equipment.

The thermal power sector is a significant contributor to the generation of electricity for the Indian economy. There is a need to rapidly scale up the capacity of generation along with reducing levels of emissions.  65% of the total power in India is generated by Thermal Power Plants (TPP) which use fossil fuels that lead to the production of harmful emissions. Thermal power stations today need to increasingly offset the power fluctuations in the grid caused by solar and wind power stations. The frequent change from constant to creeping load to cyclic load imposes new requirements on maintenance and power plant operations.

Due to this, plants are being designed for a more or less continuous operation near their design limits and their role as the mainstay of energy supply appears to be permanent. Maintenance activities in these plants are targeted to ensure continuous operation and realize cost savings. However, doing so does not always ensure meeting operational requirements.

The way conventional power stations are used has fundamentally changed with the emergence of production of electricity from renewable sources. As electricity from renewable sources of energy has taken priority on the grid, thermal power stations cannot be operated at full load. In other words these power plants may be operated at partial load but will have to increase their energy production at the blink of an  eye, making adjustments in the mechanical, process engineering and control systems. This results in the primary consequence of these cyclic loads to be impact on materials, and hence on servicing and maintenance.

At power stations with a more flexible mode of operation, the focus must be greater and more power plant operations-oriented than in the past. Plants and components operating under both constant and cyclic load require a completely different maintenance strategy from plants and components that constantly operate under full load. In case of creep strain, i.e., under continuous operation, condition-based maintenance of the materials used so far is relatively simple.

The way forward is to transform the existing baseload and mid-load power plants to becomes more flexible generating units. This will enable them to operate efficiently, profitably and also safely throughout the period of energy transition from conventional to renewable sources of energy. However this will bring with it new challenges for maintenance companies and employees who must be prepared for any new modes of operation that is required for these changes.