Chemical-looping combustion can help create CO2 neutral energy by transferring oxygen from air to fuel using metal oxide particles. Two methods were studied: direct coal gasification in the fuel reactor and using an oxygen carrier that releases O2 in the gas-phase. The second method, called chemical-looping with oxygen uncoupling (CLOU), showed higher fuel conversion rates compared to traditional chemical-looping combustion. The presence of an oxygen carrier significantly increased gasification rates by removing CO and H2. Different materials were screened for low-cost oxygen carriers, and the estimated oxygen carrier inventory needed in a real system ranged from 200 to 2000 kg/MWth depending on the fuel and oxygen carrier used.