The fourth nuclear power reactor of the Tarapur Atomic Power Station (TAPS-4) in Maharashtra, that began commercial operation from September 12, 2004, is India’s largest nuclear power reactor with a capacity of 540 MW.
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The unit reached criticality on March 6, 2005 and was connected to the western grid on June 4, 2005. It is a Pressurized Heavy Water Reactor (PHWR), which uses natural uranium as fuel, and heavy water as both moderator and coolant.