Hybrid solar systems generate power in the same way as a common grid-tie solar system but use batteries to store energy for later use. This ability to store energy enables most hybrid systems to also operate as a backup power supply during a blackout, similar to a UPS system.

Traditionally the term hybrid referred to two generation sources such as wind and solar but more recently the term ‘hybrid solar’ refers to a combination of solar and battery storage which unlike off-grid systems is connected to the electricity grid.

Basic layout diagram of a common solar hybrid system (DC coupled battery)

Why store solar energy in a battery?

Many governments and network operators have reduced the solar feed-in tariff or FiT (money or credit received for feeding solar energy to the grid). This means traditional grid-feed solar systems have become less attractive as most people are working during the day and not home to use the solar energy as it is generated, thus the energy is fed into the grid for very little return.
A solar hybrid system stores your excess solar energy and can also provide back-up power during a blackout. This is perfect for home owners although for the majority of businesses which operate during the daylight hours, a common grid-feed solar system is still the most economical choice.

Hybrid solar systems enable you to store solar energy and use it when you’re home during the evening when the cost of electricity is typically at the peak rate.

The ability to store and use your solar energy when desired is referred to as self-use or self-consumption. It works in the same way as an off-grid power system but the battery capacity required is far less, usually just enough to cover peak consumption (8 hours or less) as opposed to 3-5 days with a typical off-grid system.

Solar Hybrid Advantages
• Stores solar or low cost (off-peak) electricity.
• Allows use of solar energy during peak times (self-use or load-shifting)
• Power available during a grid outage or blackout – UPS function
• Enables advanced energy management (ie. peak shaving)
• Enables energy independence
• Reduces power consumption from the grid (reduced demand)

Solar Hybrid Disadvantages
• Higher cost than grid-feed solar. Mainly due to the high cost of batteries.
• More complex installation requires more room and higher install cost.
• Battery life of 7-15 years.
• May limit how many appliances you can run at the same time (depending on the type of hybrid inverter and its capability)

Source: https://www.cleanenergyreviews.info/blog/2014/8/14/what-is-hybrid-solar