A steam extraction turbine including a steam extraction section from which steam may be extracted from the turbine for external use prior to the low pressure section of the turbine. In order to avoid overheating of the low pressure section when the amount of extracted steam is high, there is provided a cooling steam stage immediately upstream of the low pressure section through which steam is applied to the low pressure section to prevent overheating. The cooling steam stage includes blades of the rotor and thus permits energy to be extracted from the steam applied to prevent overheating of the low pressure section, the extracted energy being used to drive the turbine thereby increasing turbine efficiency.
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