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The higher efficiency plants like supercritical units and Having the dominant role in electricity supply, thermal
advanced class combined cycle power plant would power plants are critical for grid stability and economic
require operating at a baseload/maximum time. The growth. Due to stress on the environment impact,
subcritical power plant and stranded CCPP can take renewables may take over the larger share of power
part in flexibilisation of the grid. The frequent load generation over the next few decades. However, this
swings can be taken care of by the higher ramp rate will not eliminate the addition of thermal power plant.
turbines (Gas turbines/CCPP), while the steam turbine is The thermal power plants will continue to thrive in the
used to operate at a fixed load condition. grid, with its flexible nature and stabilising/sustaining
the grid during the variation of renewable power
Also, many R&D efforts are being deployed in generation.
developing hydrogen or hydrogen-based derived fuels
viz., methanol/ammonia, and based combustion system
for thermal power plants. The hydrogen generated
from renewable power during lean power demand
conditions can be stored and used in the thermal power
plant when power demand peaks.
Authors
The capability to deliver a quick peak power is
achievable through fuel combustion route. The Aslam Basha - Sector Head Thermal
hydrogen generated through renewable energy is R Somasundaram - Dy General Manager
termed as Green Hydrogen.
Tata Consulting Engineers Limited (TCE)
Further work around achieving Net Zero, without
adding any more carbon to the atmosphere, is also
underway. The carbon emissions, which is invariably
generated through fuel combustion route presently,
will be avoided. Using surplus renewable power,
generating green hydrogen and synthesising with
captured carbon from thermal power plants to make References:
methanol or mix green hydrogen with nitrogen split India’s Energy and Emissions Outlook – NITI Aayog Working
from air to produce ammonia have all started. Small- paper
scale testing of cofiring ammonia and coal is also
being tried to reduce the existing power plant’s carbon IEA India 2018: World Energy Outlook
footprint.
IEA India 2020-In depth Energy Policy
While moving towards a cleaner energy mix, the
following options are available for thermal power
sector:

Replacing the older thermal powerplant with new
clean coal technologies like supercritical and ul-
tra-supercritical power plants

Operation of the stranded (8 GW) and stressed
(16 GW) gas-based power plant to manage the
Renewable energy variations, in India

Shift to green hydrogen fuel or hydrogen-based de-
rived fuels for use in thermal power plants, in future.

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