To transform energy from the sun into electricity to run your appliances there are three components of a PV system that need to be installed.
The solar panels (or PV modules) are usually attached to your roof but can also be ground-mounted (see mounting options) and generate electricity in the form of direct current (DC). These panels are connected together into an array and then connected to an inverter, which is usually placed in your loft.
The inverter is roughly the same size as a microwave, and converts the DC electricity into alternating current (AC), the same form used in your house to run your appliances. The inverter also makes sure that the PV modules perform at their best and generate as much electricity as they can.
The system is then connected to an export meter, which monitors how much electricity you are producing and sending back to the grid. This is separate from your import meter (that you will already have) which records how much you are taking from the grid.
Once everything is installed the whole system is automatic. It will start working early in the day as soon as there is enough light and switch off again at night. When you are producing electricity this will be used to run your appliances. If you are producing more than you need it is fed back into the grid for other people to use, and if you need more than you are producing you will take electricity from the grid. The only difference you’ll notice is lower electricity bills!
If you install an off-grid system (where you are not connected to the national grid) you will have a battery to store electricity rather than the connection to the grid. When you are producing more than you need it will charge the battery and you can use that electricity at night or when you need more than you are making.