Incorporating Concentrating Solar Power into High Renewables Penetrated Power System: A Chance-Constrained Stochastic Unit Commitment Analysis

Shan Gao,Yu Liu,Yiqing Zhang

doi:10.3390/app9112340

Abstract

High renewables penetrated power systems would be greatly influenced by the uncertainty of variable renewable energy such as wind power and photovoltaic power. Unlike wind and photovoltaic plant, concentrating solar power with thermal energy storage has similar dispatchable characteristics as conventional thermal unit. Besides, thermal energy storage could support the coordinated operation of concentrating solar power with an electrical heater, which can be employed to convert surplus electricity in the grid into thermal power stored in thermal energy storage for further utilization. In this paper, concentrating solar power is incorporated into a chance-constrained two-stage stochastic unit commitment model. The model considers the energy and reserve services of concentrating solar power and the uncertainty of renewables. The proposed method is employed to assess the role of a concentrating solar power station with thermal energy storage and an electrical heater to provide grid flexibility in high renewables penetrated power systems. Numerical studies are performed on a modified IEEE 24-bus system to validate the viability of the proposed method for the day-ahead stochastic scheduling. The results demonstrate the economic and reliable value of concentrating solar power station to the improvement of unit commitment schedule, to the mitigation of wind uncertainty and photovoltaic uncertainty, and to the reduction of traditional unit reserve requirement. It is concluded that concentrating solar power with thermal energy storage and an electrical heater is effective in promoting the further penetration of renewables.

Highlights

The acceleration of renewable energy penetration is an irresistible trend of a power system to reduce energy crises and environmental problems [1]
thermal energy storage (TES) capacity is denoted as the full-load hour (FLH) which stands for the maximum hour to support concentrating solar power (CSP) station to operate at the rated rate without illumination [46]
For stochastic power forecasts of renewable energy, 5 scenarios are generated with a Latin hypercube the stochastic power forecasts of renewable energy, 5 scenarios are generated with a Latin hypercube sampling technique for utilization in the second stage model

Summary

Introduction

The acceleration of renewable energy penetration is an irresistible trend of a power system to reduce energy crises and environmental problems [1]. Under the circumstance that the power system lacks operational flexibility, utilization of the costly electricity storage [2] and employment of the large amount of scheduled reserves [3] are common solutions to reduce the uncertainty of wind power and PV power. These methods lack cost-effectiveness in accommodating large-scale renewable energy. In this light, the development of concentrating solar power (CSP) provides a new approach for renewable energy exploitability due to its dispatchability through using high-efficiency thermal energy storage (TES) [4]. Li et al [5] and Gafurov et al [6] simulated a sole TES system and a two-tank indirect TES system respectively and analyzed the dynamic characteristics of TES to provide flexible

Results

Discussion

Conclusion