Real-time emission and cost estimation based on unit-level dynamic carbon emission factor

Abstract

The real-time carbon emission estimation of generators helps quantify the carbon emission costs and reduce power system emissions of power generation. Accurate estimation relies on the accuracy of the carbon emission factors (EFs) and power generation measurements. The dynamic carbon emission factor (DEF) of generators was proposed recently as a linear function of the output power. However, there is a significant deviation between the modelled DEFs and the actual measurement EFs, especially when the output power is low. This paper first presents the general definition of the DEF to characterize the emissions and focuses on the unit-level DEF (UDEF). The piecewise non-linear UDEF (P-UDEF) model is then proposed, which can better represent the unit emission characteristics. Then an accurate piecewise linear cost approximation method is proposed considering the segment points and extreme points of both P-UDEF and generation costs function. Last, the system carbon emissions and costs estimation are estimated by combined economic emission dispatch (CEED), and the reduction potential is evaluated. Case studies on an IEEE 30-bus system with piecewise linear cost functions show that the proposed P-UDEF can realize real-time emission and cost estimation as well as reduce the total system emissions by considering the incomplete combustion cost of generating units.