The supercritical carbon dioxide cycle has many advantages

such as high cycle efficiency

small equipment size

convenient transportation and installation

and easy to reach the critical point. Considering the huge cold energy of LNG

it can not only be used as coolant in the combined cycle system

but also the natural gas after heat transfer can be used as fuel input in the combined cycle

and the rest can be supplied to urban users. A gas turbine/supercritical carbon dioxide combined cycle system based on the utilization of LNG cold energy is proposed in this paper. Select the appropriate cost formula to calculate and analyze the investment cost

operating income and recovery cycle of the circulating power generation system in detail. The influence of some key parameters(such as maximum temperature

maximum pressure

minimum temperature

minimum pressure and shunt ratio) on the power generation characteristics and economy of the supercritical carbon dioxide cycle in the combined cycle system was studied. The results show that with the increase of each single parameter

the cost of equipment investment will first increase and then decrease

but the effect of power generation on income is dominant. Taking the yield as the measurement standard

the higher the maximum temperature

the better

the lower the minimum temperature

the better. Under other parameters

there are optimal values to maximize the yield.The key parameters were optimized by genetic algorithm to maximize the cumulative income. After optimization

the recovery cycle was 5.86 years

and the cumulative income(20 years) was 2.287 billion yuan.