M&E Contrax Resources

How Do Solar Panels Work?

Resource Highlights:

Solar panels generate DC electricity from daylight, not just sunshine.

The inverter converts it into AC electricity your property can use.

Your building uses solar first, then charges a battery if you have one, then exports any excess.

How a Solar Panel Works

Solar panels look simple on the roof, but there is a lot happening behind the scenes.

Solar PV, photovoltaic, panels convert daylight into electricity that you can use in your home or business. The system then decides what happens to that electricity, it powers your property first, charges a battery if you have one, and any excess can be exported back to the grid.

Here is a straightforward explanation of how solar panels work and what each part of the system does.

Solar panels generate DC electricity

Solar PV panels are made up of photovoltaic cells. When daylight hits those cells, they generate direct current (DC) electricity.

This happens whenever there is daylight, not just when the sun is shining brightly, which is why solar can still generate on cloudy days.

The inverter converts DC into usable AC electricity

Most homes and businesses use alternating current (AC) electricity. The inverter converts the DC electricity produced by the panels into AC electricity your property can use.

The inverter is one of the most important components in the system, because it affects:

efficiency

reliability

monitoring accuracy

whether the system can easily support a battery

Your property uses solar power first

Once the inverter produces AC electricity, your property uses it automatically.

This is where the main savings come from. Every unit of electricity you use from your solar panels is a unit you do not need to buy from the grid.

Battery storage, if installed, stores surplus energy

If your system includes a battery, any surplus electricity can be stored rather than exported immediately.

Later, when your panels are not generating, such as evenings, early mornings, or in poor weather, the battery can supply power to your home or business. This increases self consumption and often improves savings.

Excess electricity can be exported to the grid

If you generate more electricity than you need and your battery is full, the remaining electricity is exported back to the grid.

Some households and businesses receive export payments through tariffs like the Smart Export Guarantee. Export payments can add value, but most savings still come from using electricity on site first.

What affects how much solar electricity you generate?

Your system’s output depends on:

roof direction and pitch

shading from trees, chimneys, and nearby buildings

system size and layout

inverter choice and design quality

seasonal daylight hours

A proper survey is designed to assess these factors and predict realistic performance.

Frequently Asked Questions

Yes. Output is usually lower in winter because days are shorter and the sun is lower, but panels still generate electricity whenever there is daylight.

Most standard systems switch off during a power cut for safety reasons. Backup capability requires specific system design and equipment.

In many cases, yes. If your system is designed to be battery ready, adding storage later can be straightforward.