Integrated once through cooler water and steam sharing system for multi-unit gas turbine combined cycle power blocks

A method of operating a power plant system comprising a set of gas turbines, a first once-through cooling (OTC) unit, a second once-through cooling (OTC) unit, a heat recovery steam generator (HRSG) unit and a set of steam turbines, wherein the method comprising:

• supplying, by the first OTC unit to the HRSG unit, steam, wherein the first OTC unit is associated with a first gas turbine of the set of gas turbines, and wherein the first gas turbine is in an open cycle mode;
• supplying, by the second OTC unit to the HRSG unit, steam, wherein the second OTC unit is associated with a second gas turbine of the set of gas turbines, and wherein the second gas turbine is operating in a combined cycle mode;
• generating, by the set of gas turbines, energy, wherein the set of gas turbines comprises the first gas turbine and the second gas turbine;
• generating, by the HRSG unit, specific steam based on the steam supplied to the HRSG unit from the first OTC unit and the steam supplied to the HRSG unit from the second OTC unit, wherein the HRSG unit is associated with the second gas turbine;
• and
• generating, by the set of steam turbines, energy based on the generated specific steam, wherein the generated specific steam is supplied from the HRSG unit to the set of steam turbines.