Everything You Need To Know About Solar Panels

Solar power is one of the fastest-growing renewable energy sources in many countries around the world. With the sun able to provide enough energy to power the world at a few times over, it makes sense that humanity is seeking to harness more and more of this energy to power our society.

But, beyond their usage, many people don’t know much about solar panels themselves. We’ve put together this beginner’s guide to what solar panels are, how they came about, and which types are most suited to different uses.

What are solar panels made of?

Solar panels are made up of a series of photovoltaic cells joined together in strings. These strings then form a module which is housed behind glass, which is what we know as a solar panel.

These solar panels can then be joined together to form a solar PV system and used to generate a specified electrical output.

Photovoltaic cells are formed of at least two thin layers of semi-conducting material, most commonly silicon, which can come in the form of monocrystalline or polycrystalline structures.

Who invented solar panels and when?

Solar power has been around in some form for hundreds of years - even as far back as the 7th century BC!

Ever since the day people figured out how to light fires using the sun and some glass, humanity has been trying to find more and more ways that the sun can provide power to the world.

But in terms of the solar power we know today, there have been lots of inventors and companies that have played a role in the development of solar panels. Let’s look at some of the key events throughout the 20th and 21st centuries.

    • 1873 - English electrical engineer Willoughby Smith discovers that selenium shows signs of photoconductivity. In other words, the electrical resistance of selenium varies significantly depending on the amount of light falling on it.
    • 1883 - American inventor Charles Fritts is credited with developing the first working solar cell. The cell was made of selenium and a light coating of gold and produced less than 1% efficiency.
    • 1905 - Albert Einstein publishes a paper explaining the photoelectric effect on a quantum basis.
    • 1939 - Russel Ohl, an American engineer, designs a solar cell which is still used in many modern solar panels.
    • 1954 - Bell Labs, industrial research and scientific development company, announces it has invented the world’s first practical silicon solar cell, which runs at 6% efficiency. The invention is praised widely, and The New York Times predicts that solar cells will lead to “the harnessing of the almost limitless energy of the sun for the uses of civilization.”
    • 1960 - Hoffman Electronics creates a 14% efficient solar cell
    • 1978 - The world’s first solar-powered calculators go on sale
    • 1985 - The Centre for Photovoltaic Engineering created 20% efficient silicon cells at the University of New South Wales.
    • 2010 - Sitting US President Barack Obama orders installation of additional solar panels and a solar water heater at the White House!
    • 2015 - Tesla announces the product launch of Tesla Powerwall, a rechargeable lithium-ion battery intended for home energy storage.

Different types of solar panels

There are 3 main types of solar panel; monocrystalline, polycrystalline, and thin-film.


Monocrystalline (or single-crystalline silicon) solar cells are made from cylindrical ingots of silicon. Monocrystalline silicon is produced using something called the Czochralski process, which is used to grow single crystals of semiconducting materials.

These panels are easy to recognise due to their uniform appearance and even colouring. This is because the cylindrical ingots are cut down to form silicon ‘wafers’ and only contain high-purity silicon. This wafer shape also helps to improve performance and reduce the production costs of monocrystalline panels.


As opposed to its monocrystalline counterpart, polycrystalline silicon is not produced using the Czochralski process. Instead, the process is much simpler and requires only to melt and pour raw silicon into a square mould, followed by cooling and cutting into perfectly square wafers.

Polycrystalline panels can be identified by their speckled blue appearance, compared to the pure blue of monocrystalline and thin film panels.

Thin Film

Thin film solar panels tend to be reserved for commercial use due to their low efficiencies, as thin film PV systems there require a large amount of space to produce enough electricity. In the manufacturing process, one or more thin layers of photovoltaic material are deposited onto a substrate. To date, most thin film panels tend to operate at between 7-13% efficiency, with this predicted to rise to 10-16% in the future.

Despite their low efficiency, thin film panels can be a popular choice for commercial businesses, as the low production costs mean thin film panels tend to be one of the cheapest types of solar panel available.

Monocrystalline Polycrystalline Thin Film*
Higher efficiency Lower efficiency Lowest efficiency
Higher space efficiency Lower space efficiency Lowest space efficiency
Longer warranty Shorter warranty Shorter warranty
More expensive Less expensive Least expensive

*Thin film solar panels are rarely suitable for residential use, as a lot of space is required to house a thin film PV system which meets your electrical consumption needs.

Uses of solar panels

Solar panels have been used to power everything from calculators and watches through to entire buildings. While rooftop solar for domestic electricity generation is by far the most common usage, nowadays uses range from positioning panels on the top of trains and buses to help power transport systems, to using them to power street lighting, and even to heating outdoor pools!

Solar power has also seen significant uptake when it comes to mobile phones and wearable tech. Many people now carry a powerbank to keep their phones, tablets, and wearable tech charged throughout the day, with the sun offering an easy way to keep the powerbank itself topped up.

Ready to go solar?

Our solar panels come in a range of sizes to suit your needs. Get an estimate of costs and savings using our calculator tool, then get in touch for specialist advice and to move things forward.

  • Use our Solar Calculator to discover the benefits of Tonik Solar (it takes less than two minutes!)
  • Talk to us for specialist advice and to discuss next steps 0333 344 2686 (option 3)
  • We'll work with you at every step, to deliver a solution you are delighted with

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