On Grid or Off?

On Grid , Off Grid  or Grid Connected (hybrid)

Grid Tied

This the cheapest option. But will typically not work in a power cut. That said there are lots of interesting things you can do with a purely on grid system. Such as using a diversion controller to heat hot water when power is not being used by the house.  Depending on country and government there may be Feed In Tariffs, or other schemes such as net metering.  Unfortunately in the UK (where I am) Neither of these apply and the payments from utilities are pretty meagre usually only at wholesale cost per unit exported.

However grid tied PV can work very well in conjunction with an air source heat pump to drastically reduce heating costs.

Offgrid

Using solar panels, a battery and an inverter to provide power. To provide full western style living comfort using this method works out extremely costly. Either change your behaviour or accept that it will cost a large amount of money.

The most simple application for this would be a 12v panel with a PWM controller running 12v loads such as lights, device charging or internet router.  At the other end you could have AC coupled wind and solar providing your own island scale minigrid.

Hybrid

Fairly new development. Also called grid interactive.

If you have access to the grid and want to grid tie, but also want to be insulated against power cuts and use your own electricity at peak times for load shifting grid interactive is pretty interesting. Usually the inverter can be programmed to behave in a certain way such as:

Grid priority. Acts like a giants UPS for your house or a single priority circuit. Keeps the batteries charged and uses the solar power for current loads and exports to the grid

Solar priority. Uses the solar and batteries to completion before importing grid power.