How Is Solar Energy Converted Into Electricity?

Solar energy is converted into electricity through the photovoltaic effect, a process where sunlight, composed of photons, agitates electrons in a semiconductor material (like silicon) within solar panels.

Here’s a deeper look into the full process:

Basic solar power components

To find out how solar power works, you need to understand how panels are made. Many solar panels use silicon, one of the planet’s most common elements.

However, since creating silicon crystals of suitable quality is difficult and expensive, home solar systems are usually built from similar but less expensive materials, such as copper, indium, gallium and selenide (CIGS).

These aren’t as efficient as high-quality silicon but still provide adequate power at a reasonable cost. 

During manufacturing, small amounts of other elements are introduced to alter the electrical properties of the silicon atoms. Strips of negative (n-type) silicon, which has an extra electron and positive (p-type) silicon, which is missing one electron, are sandwiched together. 

The combination forms a photovoltaic cell. And when multiple photovoltaic cells are placed side by side under glass, they give us common solar panels.

Inside each solar panel is a conductive metal plate connected to wires that lead to a fused array combiner. Energy from the array is sent through an inverter, which transforms the initial direct electrical energy into the alternating electrical current required to power human-made structures and connect to the electrical grid.

Turning solar power into electricity

Visible sunlight is composed of invisible particles called photons. These have energy but zero rest mass. When the photons collide with other particles, their energy is converted to other forms depending on the kind of atoms they touch. Most collisions create only heat. 

But solar technologies convert sunlight into electrical energy when the photons make electrons in the atoms so agitated that they break away and move about freely.

The n-type silicon electrons seek out the ones in p-type silicon to replace their missing electrons, and the flow between the two types is produced. 

The remarkable properties of semiconductors like silicon make it possible to sustain electrical imbalances. This means a steady supply of electricity generation as long as photons hit the solar panels. The current is collected by wires and carried throughout the system, eventually connecting to the electrical grid to generate electricity for homes and businesses.

4 factors that impact solar energy production

Households should consider four major factors during and after the installation of their residential solar energy systems.

• Shade

Shaded solar panels won’t produce the same amount of solar energy as those in direct sunlight. If your roof is sun-deprived by un-trimmable trees or buildings, solar energy may not be your best choice.

• Seasonality

Like the weather, solar energy production varies day-by-day and month-to-month. A cloudy, winter day won’t be as productive as a sunny, summer one. But it’s important to focus on the year-round picture.

For example, snow can sometimes reflect light and improve PV performance. So, in reality, a cold month will only become a solar power antagonist if slush covers the panels. As long as the sun shines, solar panels can continue to generate solar power. 

• Tilt

Unlike a pinball machine, solar panels can benefit from good tilting. The direction your home is facing, its location, and even your roof’s pitch have a significant effect on how well a residential solar system works. 

Ideally, solar panels should be at the same angle as the latitude where they’re mounted. Pitches between 30 degrees to 45 degrees usually work well in most scenarios. 

• Azimuth

The solar azimuth angle is the compass direction from where the sunlight is coming. At noon, the sun’s light comes from the south in the Northern Hemisphere and from the north in the Southern Hemisphere. 

The wrong azimuth angle could reduce the solar energy produced by a solar home panel by up to 35%. An azimuth of zero (facing the equator) is usually the best choice.

Concentrating Solar Thermal Power (CSP) is another innovative technology that focuses sunlight on a small area to produce electricity more efficiently, contributing significantly to meeting the entire world's energy consumption.

Do you have questions about how solar power works? Our solar advisors are here to help you!