First things first:
Using online tools we can see if there is enough roof space and if your house is suitable for a solar photovoltaic system.
All we need is the address where you want the solar photovoltaic system installed.
Now have a look at your last electricity bill. There you find the information about your average daily consumption - the units of electricity you're using. Think about what your aim is with putting solar onto your roof. Some just want to reduce their electricity bill, others want to get rid of it all together. Some want to upgrade the worth of their home, before going on the market, others want to become electricity independent.