Overview of fossil fuel-based hybrid power generation systems within mini-grids – The experience of storage-less PV system integration into three of the Great Algerian South mini-grids

•An overview of Hybrid Power Generation Systems within Mini-grids is presented.•A novel survey of PV integration into existing fossil fuel-based Power Generation Systems is performed.•Great Algerian South mini-grids are introduced and the experience of PV integration into three of them is assessed.•Further approaches to increase the PV penetration level of the Hybrid Power Generation Systems are proposed.