Optimal configuration of a two-level integrated rural energy system for counting and biogas digester warming

Abstract

This paper proposes a strategy to use wind power (WP) that cannot be fully consumed at the load side for biogas digester (BD) heat augmentation to improve the utilization rate of biomass while promoting the consumption of WP, in view of the anti-peak nature of WP and the low gas production of BD at night in winter. In this paper, based on the model of rural integrated energy system (RIES) with biogas digester heating, a double-layer optimization model with minimum investment cost in the upper layer and optimal operation in the lower layer is developed. And then the Karush–Kuhn–Tucker (KKT) condition is used to convert the lower layer model into the constraints of the upper layer model, The Big-M method is used to linearize the nonlinear problem, and the model is transformed into a single-layer mixed integer linearization model. Finally, a use case of the algorithm is established and the CPLEX solver is called to solve the problem.

Keywords

• WP
• BD heat
• The utilization rate of biomass
• RIES
• KKT