With the proposal of the dual carbon goal, it is necessary to accelerate the construction of a safe, economical and low-carbon power system in China. However, a high proportion of thermal power installed capacity has high CO2 emissions, and large-scale renewable energy installations will lead to poor reliability of the power system. The integration of energy storage and carbon capture equipment can take into account the issues of carbon emissions and system reliability to a certain extent, but at the same time, it will also lead to an increase in the cost of power generation. Based on an energy base, the carbon emission intensity and reliability indicators of the system under different renewable energy installed proportions were analyzed, and the carbon capture amount and the required amount of carbon capture were given when the system met the carbon emission and reliability constraints under different technical routes. The system economy after unified carbon emission and reliability indicators was compared. The results show that through biomass coupled carbon capture technology, zero carbon emission or even negative carbon emission can be achieved in the power system. Energy storage can effectively improve system reliability. For a system with a total installed capacity of 5 000 MW, for every 20% increase in the proportion of installed renewable energy, energy storage equipment with a power of 850-875 MW needs to be connected to meet the reliability requirements of the system. As carbon emission requirements increase, the cost of system power generation continues to rise, and the system has the highest economy at 60% of installed renewable energy under the premise of meeting carbon emission and reliability constraints.