Evaluate the capacity of electricity-driven water facilities in small communities as virtual energy storage

Abstract

In small communities, such as small islands, campuses of universities/industrial parks/lab facilities, and remote villages/cities, the Water-Energy Nexus (WEN) operators generally need to purchase electricity from the power grid to meet a portion of their power demand. The WEN of these communities creates new opportunities of providing virtual energy storage (VES) and virtual power plant (VPP) services to the power grid by properly controlling their electricity-driven water facilities (EDWF). This paper investigates the capacity of EDWFs in small communities as VES and VPP. Small communities in four different types of areas, e.g., island, desert, urban, and rural, are studied based on their geographical specifications, to evaluate and compare the capabilities of their WENs as VES and VPP respectively. WENs with high penetration of photovoltaic resources are considered, for which battery energy storage systems (BESS) are needed. An optimization approach of operating the EDWFs as VES is proposed to reduce the required size of BESSs. The state-of-the-art convex technologies are adopted to reduce the computational burden of the developed optimization models which are large-scale mixed-integer nonlinear programming problems. Besides, the WEN of small communities is modeled as a VPP to provide spinning reserve energy for the power grid in emergency conditions. This paper also describes how the EDWFs can be controlled to serve as a virtual system and provides substantial benefits for the small communities. Numerical results validate that it is economically beneficial to operate the WENs of small communities as VES or VPP for renewable energy management of power grids.