Power production plant including liquid oxygen storage and method of operation of the power production plant

A method of operating a power plant, the method comprising:

• producing power in the power plant by expanding through a turbine a pressurized combustion stream arising from combusting a fuel with oxygen in a combustor in a presence of a pressurized carbon dioxide circulating fluid;
• producing, using the power, liquid oxygen (LOx) from ambient air in an air separation unit (ASU) that is configured for independent operation at a full load capacity or a partial load capacity;
• delivering the LOx from the ASU to a liquid oxygen storage vessel;
• providing the LOx from the liquid oxygen storage vessel in a condition suitable for use as at least a portion of the oxygen in the combustor;
• wherein operation of the power plant and the producing of the LOx in the ASU are independently controlled relative to an economic variable so that one or more of an amount of the LOx that is produced in the ASU, an amount of the LOx that is delivered to the liquid oxygen storage vessel, and an amount of the LOx that is provided for use in the combustor is adjusted responsive to a change in a value of the economic variable and
• while the power plant is generating the power, determining a price of the power is above a threshold value;
• in response to the price of the power being above the threshold, shutting down the ASU or placing the ASU in a standby mode and producing the power using LOx from the liquid oxygen storage vessel.