A clean energy system, a renewable energy system or a zero emission energy system (ZEES) to utilize CO2 waste. The energy system may include a fuel processor, an energy catalytic reactor, and a power generator. The fuel processor may catalytically convert the CH4 component in the natural gas, biogas or syngas into a reformate including H2, CO, CO2 and H2O species. The energy reactor may convert the reformate in gas form into a liquid fuel. The power generator may generate power using an output of the fuel processor and/or an output of the energy reactor.