Why do modern steam power plants use a regenerative feedwater heating system?

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Answer 1

Use of a regenerative feedwater heating system

Modern steam power plants use regenerative feedwater heating systems primarily to improve thermal efficiency. This is because:

By preheating the feedwater using steam extracted from intermediate stages of the turbine, the energy required in the boiler to convert water into steam is reduced.
This reduces fuel consumption for the same power output, leading to better efficiency based on the Rankine cycle with regeneration.
Regeneration increases the average temperature at which heat is added in the cycle, which directly boosts the cycle efficiency (per Carnot's principle).
With improved efficiency, lower emissions per unit of electricity generated are achieved, making the plant more environmentally friendly.