Economic and environmental analysis of coupling waste-to-power technology to integrated energy system (IES) using a two-layer optimization method

Integrated energy system (IES) could improve the energy efficiency and reduce carbon emissions through multienergy production, storage, transportation, and supply. However, the energy flow in traditional IES is usually one-way: from electricity to heat/cold, or from heat to cold. Coupling waste-to-power (WTP) may also convert waste heat to electricity, thereby further improving the flexibility and reducing pollutant emissions. Therefore, this work focuses on exploring the value and applicable scenario of IES-WTP, from the perspective of economics and carbon emissions. A two-layer optimization method is proposed to realize the multi-objective optimization of both the operation strategy and system design. Then this IES-WTP system is compared with traditional IES considering three different load profiles. Results indicate that coupling WTP could significantly improve the overall performance of IES. Specifically, the annual carbon emissions could be reduced by up to 13%, and the annual costs could also be reduced with the same emissions. As the WTP efficiency improves from 9% to 18%, the emission reduction will further increase by 6%. In addition, this IES-WTP system is found more applicable for the area where the electric load is higher or close to the heat/cold load, but is not suitable for the area where heat load is much higher than electric/cold load.