At which location was the first commercial nuclear power plant in India set up for electricity generation?

Introduction / Context:
Nuclear power plants are an important part of India's energy mix, and general knowledge exams often ask about the first nuclear power station or key reactor locations. This question specifically asks where the first commercial nuclear power plant in India was set up to generate electricity for the grid.

Given Data / Assumptions:

• We are concerned with the first commercial nuclear power plant used for electricity generation. • Options list several nuclear power plant sites in India. • We must select the earliest such plant.

Concept / Approach:
India's first commercial nuclear power station is the Tarapur Atomic Power Station in Maharashtra. It was developed with technological assistance and commissioned before other major plants such as Narora, Kaiga, Koodankulam and Rawatbhata. Therefore, the approach is to recall the chronological development of nuclear power plants in India and identify Tarapur as the first.

Step-by-Step Solution:
Step 1: Remember that Tarapur Atomic Power Station, located in Maharashtra, was commissioned in the late 1960s as India's first commercial nuclear plant. Step 2: Check the other options. Koodankulam in Tamil Nadu and Kaiga in Karnataka are relatively new plants that came much later. Step 3: Narora in Uttar Pradesh and Rawatbhata in Rajasthan were also commissioned after Tarapur. Step 4: Since Tarapur clearly predates the others as a commercial station, it must be the correct answer. Step 5: Select Tarapur as the location of the first nuclear power plant in India for electricity generation.

Verification / Alternative check:
Standard exam preparation books and nuclear energy summaries consistently state that Tarapur Atomic Power Station was the first nuclear power plant in India. It is often paired with questions about its location in Maharashtra and the type of reactors used there. This repeated presentation confirms Tarapur as the right choice.

Why Other Options Are Wrong:
Koodankulam: A newer nuclear power plant in Tamil Nadu, developed in later phases of nuclear expansion. Kaiga: Located in Karnataka, it was commissioned after Tarapur and is not the first plant. Narora: A nuclear power station in Uttar Pradesh that came into operation later than Tarapur. Rawatbhata: Hosts the Rajasthan Atomic Power Station, but its commissioning followed Tarapur in the timeline.

Common Pitfalls:
Students sometimes confuse "first nuclear reactor" or research reactors with the first commercial power plant, and they may also mix up locations like Rawatbhata and Tarapur. Another pitfall is remembering only the newest or most controversial projects and ignoring historical ones. To avoid this, pay special attention to lists of "firsts" in Indian science and technology.

Final Answer:
The first commercial nuclear power plant in India was set up at Tarapur.