Green energy is driving the evolutions of energy industry and carbon emission is becoming an important concern. Considering the increasing couplings among various energy sectors

this paper investigates multi-period optimal energy flow and energy pricing in carbon-emission embedded integrated energy systems

including electricity

natural gas

and district heating networks. Firstly

an optimal scheduling model of integrated energy systems was proposed in this paper. The models of DC power flow

natural gas pipeline flow and heating network energy flow are presented and linearized for the optimization problem. Natural gas-fired generators and combined heat and power (CHP) units are modeled as coupling components of electricity-gas and electricity-heating networks. Then

based on the optimal scheduling model

the locational marginal prices (LMP) for electricity

natural gas and heating network are determined. Moreover

the carbon emission caused by energy production has been taken into account in the optimal scheduling and energy pricing process. Finally

case studies on a combined network consisting of IEEE 39-bus system

Belgium 20-node natural gas system and 6-node heating system demonstrate the effectiveness of the proposed model and the impacts of carbon emission on system scheduling and LMP.