Units 1 and 2 were brought online for commercial operation on 28 October 1969 with an initial power of 210 MW of electricity.

More recently, an additional two pressurised heavy water reactor (PHWR) units of 540 MW each were constructed by BHEL, L&T and Gammon India, seven months ahead of schedule and well within the original cost estimates.

The personnel operating the power plant live in a residential complex called T. A. P. S. colony, 19°48′58″N 72°44′35″E / 19.816°N 72.743°E / 19.816; 72.743 which is a fifteen-minute drive from Boisar, the nearest railway station.

Due to this, the residential complex has a very Indian small-town look, with neat sidewalks, spacious houses, a club with tennis courts, swimming pool, a commissary etc.

In 1974 after India conducted Smiling Buddha, its first nuclear weapons test the West chose to no longer honour its agreement to supply the plant with enriched uranium.

Nuclear fuel for TAPS has subsequently been delivered from France, China and Russia under IAEA safeguards.

[11] In 2011, AERB formed a 10-member committee, consisting of experts from Indian Institutes of Technology (IIT) and India Meteorological Department (IMD), to assess the vulnerability of the Tarapur to earthquakes and tsunamis.

[12] A. Gopalakrishnan, former director of AERB, said that since Tarapur's reactors are much older than the Fukushima units, they should be immediately decommissioned.

[13] But the reactors are planned for restart in November 2024 after replacement of parts in the primary recirculation system.