Storage size determination for grid-connected photovoltaic systems

Yu Ru, Jan Kleissl, and Sonia Martínez
IEEE Transactions on Sustainable Energy, 4 (1) (2013) 68-81

Abstract:

In this paper, we study the problem of determining the size of battery storage used in grid-connected photovoltaic (PV) systems. In our setting, electricity is generated from PV and is used to supply the demand from loads. Excess electricity generated from the PV can be stored in a battery to be used later on, and electricity must be purchased from the electric grid if the PV generation and battery discharging cannot meet the demand. The objective is to minimize the electricity purchase from the electric grid while at the same time choosing an appropriate battery size. More specifically, we want to find a unique critical value (denoted as Ec-max) of the battery size such that the cost of electricity purchase remains the same if the battery size is larger than or equal to Ec-max, and the cost is strictly larger if the battery size is smaller than Ec-max. We propose an upper bound on Ec-max, and show that the upper bound is achievable for certain scenarios. For the case with ideal PV generation and constant loads, we characterize the exact value of Ec-max, and also show how the storage size changes as the constant load changes; these results are validated via simulations.

File: main.pdf

Bib-tex entry:

@article{YR-JK-SM:13,
author = {Y. Ru and J. Kleissl and S. Mart{\'\i}nez},
title = {Storage size determination for grid-connected photovoltaic systems},
journal= {IEEE Transactions on Sustainable Energy},
volume = {4},
number = {1},
pages = {68-81},
year = 2013
}