Page 242 - Hybrid-Renewable Energy Systems in Microgrids

Solar–wind hybrid renewable 12

energy system: current status

of research on configurations,

control, and sizing methodologies

Piyali Ganguly, Akhtar Kalam, Aladin Zayegh
Victoria University, Melbourne, VIC, Australia

1 Introduction

Renewable energy is obtained from natural resources that are not depleted when used,
such as the wind or solar power. Renewable energy systems (RES) are being widely
accepted as an alternative to standard conventional energy sources due to depletion
of natural resources and their consequential environmental impact [1]. The necessity
to prevent the weather changes and the increase in the costs of traditional sources of
energy have motivated many nations to provide innovative energy strategies promot-
ing the use of RES. Renewables now are established around the world as mainstream
sources of energy [2]. Rapid growth of RES particularly in the power sector, is driven
by several factors including the improving cost-efficiency of renewable technologies,
dedicated policy initiatives, better access to financing, concerns about energy security
and the environment, growing demand for energy in developing and emerging econo-
mies, and the need for access to modern energy [3].
Fig. 12.1 represents global renewable power capacity and annual growth rate,
2000–15 [4].
Among all the RES, the utilization of solar and wind energy system has become
increasingly popular due to modular nature [5,6]. The field of solar–wind has experi-
enced a remarkable growth for past two decades in its widespread use of standalone to
utility interactive solar–wind systems [6,7].
RES can be of two types; Grid-connected and standalone. Grid connected systems
are the systems which are connected to the utility grid. They can draw power from the
grid when the power generated by RES is less than the load demand. Also during
the off- peak demand times, the excess power generated by the RES can be fed back
to the grid. Standalone systems are independent of the grid power.

1.1 Grid connected systems
Grid-connected systems can be of two types [8]. The first type of grid connected sys-
tems is mainly responsible for catering the local needs for electricity and any surplus
generation from the generators will be fed into the grid. When there is a shortage of
electricity generated from the RES due to poor weather conditions, the required power
Hybrid-Renewable Energy Systems in Microgrids. http://dx.doi.org/10.1016/B978-0-08-102493-5.00012-1
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