The bidder should have executed contracts on engineering, procurement and construction (EPC) basis for at least one (1) no. coal based/lignite based/power plant of installed capacity not less than 250 MW which has been commissioned during the last 10 years and has been in successful operation for at least one(1) year (from the date of achieving full load) as on 7 days prior to the date of opening of the bid. The scope of work of such reference plant should have necessarily included design, engineering, supply, erection and commissioning (or supervision of erection and commissioning) on turnkey basis (with all associated mechanical, electrical, civil and structural works) of either: (a) Main power plant equipment (Boiler - Turbine-generator or Gas Turbine- HRSG - STG) with all associated integral auxiliaries. Or (b) Coal/lignite handling plant, ash handling plant, cooling tower and water system (water treatment/waste water treatment, DM plant and circulating water system) of a coal / lignite based power plant.