Benefit analysis and preliminary decision-making of electrical and thermal energy storage in the regional integrated energy system

Abstract

The ambitious goal of decarbonization has promoted regional integrated energy system (RIES), which enables interaction between energy consumption and supply sectors with different characteristics to improve energy application efficiency. Compared with single energy storage, multiple energy storage (MES) may have the potential to provide better flexibility and lower costs, but the necessity of applying and the preliminary decision-making principles have not been very clear to users and investors. To solve this problem, this study based on the typical RIES framework on the demand-side, firstly proposes multi-dimensional evaluation indexes from the aspects of renewable energy consumption, carbon emission reduction, load shifting and economic property; then, taking a commercial area as a case, develop the optimal operation strategy of the minimum total daily cost to analyze the operation and synergistic benefits under four scenarios; influencing factors such as energy storage capacity, load demand and region types are considered though sensitivity analysis; finally, suggestions for the preliminary decision-making of MES are given. The results show that the combination of electricity and thermal energy storage can realize the complementary advantages of single energy storage technology, making the contribution of different kinds of energy storage benefits more balanced on the basis of reducing the total cost, which significantly improves the flexibility of the energy system; the electricity-thermal energy storage has obvious advantages in the four functional areas involved herein; however, as the storage capacity increases to the saturation value, the marginal effect appears, and the corresponding total benefits tend to stabilize gradually. The preliminary decision-making of applying energy storage is carried out according to the external and internal levels, respectively according to the control requirements of energy storage investment cost, the allocation of renewable energy in the target area, as well as the regional energy consumption structure and specific needs. This principle can provide a reasonable basis for decision-makers and promote the application and development of multiple energy storage.