Combined heat and power system using and producing co2 and method of operation

A combined heat and power (CHP) system, the CHP system comprising:

• an oxygen-air separation device;
• a combustion system having a combustion chamber and a solid fuel feed mechanism, the combustion chamber having an gas inlet and an output conduit, the gas inlet being fluidly coupled to the oxygen-air separation device, the combustion chamber configured to generate a CO2 exhaust gas that substantially comprises CO2 gas;
• a first proportional valve fluidly coupled to the gas inlet and configured to control a flow of expanded heated CO2 working gas to the gas inlet, the expanded heated CO2 working gas comprising at least a portion of the CO2 exhaust gas;
• a high temperature heat exchanger fluidly coupled to receive the CO2 exhaust gas therefrom and output a cooled CO2 working gas;
• and
• a gas turbine having a compression section and an expansion section operably connected on a drive shaft, the compression section receiving the cooled CO2 working gas at an inlet and compress the cooled CO2 working gas, the gas turbine receiving a heated CO2 working gas at an inlet to the expansion section and expanding the heated CO2 working gas and generate work therefrom.