Table: power_station_details
Columns: stage
unit_number
installed_capacity_mw
date_of_commissioning
status
tg_set_provider
boiler_provider

Question: What are Unit 2's dates of commissioning?
SQL: SELECT COUNT("date_of_commissioning") FROM power_station_details WHERE "unit_number" = 2

Question: What is the boiler provider for Bhel, India's TG Set provider?
SQL: SELECT "boiler_provider" FROM power_station_details WHERE "tg_set_provider" = 'BHEL, India'