14 Solar Energy Facts : Capacity, History, Uses and More

Solar energy is the most abundant energy source available to us. Globally, there is a growing effort to harness solar energy as a renewable source of electricity. Solar panels are becoming cheaper and more efficient, so more and more of the world’s power is coming from solar energy.

As technology advances, we are developing new and innovative ways to harness and utilize solar energy, making it an exciting field with vast potential for the future. On this page, we will explore some fascinating facts about solar energy that highlight its importance within our increasingly environmentally-conscious world.

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Covering 50,000 Square Miles With Solar Panels Could Power The Entire Planet.

As the world moves away from fossil fuels and towards renewable energy sources, it is interesting to consider what a purely solar future would look like.

The world’s energy consumption is currently estimated to be between 25,000 and 30,000 terawatt hours (TWh) per year. Assuming that the average 2m² solar panel can generate 1kWh per day, we would need to cover around 50,000 square miles with solar panels to meet the world’s energy demands.

To put this into perspective, this is less than just 2% of the area of the Sahara Desert.

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The Sun Emits Enough Energy In 90 Minutes To Power The Entire World For One Year.

The sun is an immense source of power that is constantly emitting energy towards the Earth.

In the middle of a clear sunny day, roughly 1000 Watts of solar energy hits each square meter of the Earth's surface. Once averaged across a whole year and a whole day this is reduced to 342 W/m². This still amounts to roughly 44 quadrillion watts, making solar energy the most abundant source on Earth by a large margin. This light travels to earth after travelling approximately 8 minutes from the Sun to reach us.

However, not all of this is usable energy, as around 30% is reflected back into space by the Earth’s upper atmosphere and clouds.

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Solar Panel Technology Was First Discovered In 1839.

Solar energy can be harnessed via the photovoltaic effect. This is the principle in which a material absorbs energy from the sun and then releases electrons that can be diverted into a usable current.

The first known person to make use of this effect was nineteen-year-old French physicist Alexandre Edmond Becquerel during an experiment in his father’s laboratory.

He believed that he could generate an electrical current by shining light onto an electrode submerged in a conductive solution. To do this, he placed silver chloride in an acidic solution and illuminated it whilst it was connected to platinum electrodes. In doing so, Becquerel became the first known person to create a solar cell.

Following on from this discovery, it would then take over one hundred years for the first silicon-based solar panel to be developed by Bell Laboratories in 1954.

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The International Space Station Is Entirely Solar Powered.

Perhaps one of the most successful applications of solar panels is on the International Space Station (ISS).

The ISS is a large research facility that is currently in low orbit around Earth. Home to crews of astronauts and cosmonauts from across our world, the ISS requires energy to power its onboard facilities. This energy comes entirely from the sun.

The ISS is split into different segments which are powered by solar arrays. The entire ISS is powered by eight large solar array wings which each contain two solar array blankets made up of over 32,000 photovoltaic cells. A single solar array blanket provides 105 square meters of solar cells.

The solar arrays are not always in the path of direct sunlight and are sometimes shadowed by the Earth or the ISS itself. Therefore, around 60% of the collected solar energy is stored in nickle-hydrogen (NiH₂) batteries to provide a constant and reliable energy source during these times.

Solar panels in space are subject to more of the sun’s energy than solar panels on Earth as there are no clouds or atmosphere.

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Solar Technology Can Be Used In Paint.

Researchers are constantly looking for new ways to harness more of the solar energy available to us. Solar panels are often large pieces of hardware. This restricts where they can realistically be installed.

One idea is to generate electricity from the sun using liquids - these are known as solar paints.

There are currently three different avenues for this technology which are being explored:

• Quantum dot solar cells: First developed at the University of Toronto, quantum dots are nanoscale semiconductors that can capture a broad spectrum of light and turn it into a useable electrical current. The very small size of these solar cells would allow them to be painted onto existing surfaces, hence they have been given the nickname ‘photovoltaic paints’.
• Hydrogen-producing solar paint: These solar paints from the Royal Melbourne Institute of Technology (RMIT) can generate electricity from water vapour. The paints, containing molybdenum-sulfide, absorb moisture from the air and use solar energy to break down the water molecules into oxygen and hydrogen. The hydrogen can then be used produce energy.
• Perovskite solar paint: Perovskite materials have a specific crystal structure that can be used to create highly efficient solar cells. Interestingly, these materials can still work as semiconductors in liquid form, making them ideal for solar paints. In 2014, researchers at the University of Sheffield developed the first spray-on solar cells using perovskites.

Though this technology still needs some development, the potential applications of solar paints are vast. Solar paints could be added to existing solar units to improve efficiency, or applied to exterior walls of buildings where conventional solar panels can not be installed. Solar paints could also be applied to electric vehicles to charge them.

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Solar Panels Could Produce 50% Of The World's Electricity By 2050.

In the push to meet global zero-emission targets, solar energy has become one of the fastest growing energy sources. The global amount of electricity generated from solar energy has increased by over 1000% in the past decade, and solar energy now accounts for nearly 6% of the world’s total energy consumption.

The rapid increase in solar energy generation has been driven by two major factors: decreased manufacturing costs and rapid set up times. A solar farm can be constructed in as little time as one year, whereas a wind farm requires up to three years to complete.

With the current rate of growth, it is estimated that one half of our world’s electricity could come from solar panels by 2050.

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The Biggest Solar Farm In The World Could Power Cyprus.

Solar farms are large scale power systems where solar panel arrays cover vast amounts of land to generate energy for the grid. As our demand for renewable energy increases, solar farms are becoming larger and larger.

As of June 2024, the largest solar farm in the world is XinJiang Solar Farm in China. This solar farm has a huge capacity of 5 Gigawatts and covers over 300 square miles making it around the same size as New York City.

The amount of energy generated by this singular solar farm is enough to power an entire country. Cyprus, Papua New Guinea, and Jamaica all have yearly energy consumptions that are lower than the solar farm’s capacity.

The current ten biggest solar farms in the world are as follows:

Solar Farm	Country	Capacity (GW)	Size (km2)
Xinjiang Solar Farm	China	5	809
Golmund Solar Park	China	2.8	609
Bhadla Solar Park	India	2.7	56
Mohammed bin Rashid Al Maktoum Solar Park	UAE	2.62	77
Pavagda Solar Park	India	2.05	52.6
Benban Solar Park	Egypt	1.8	37
Tengger Desert Solar Park	China	1.5	43
Sudair Solar PV Project	Saudi Arabia	1.5	30.8
Noor Abu Dhabi Solar Power Project	Abu Dhabi	1.2	8
Datoon Solar Power Top Runner Base	China	1.1	2.4

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Solar Panel Costs Have Dropped By 82% In The Last Decade.

As solar panels have risen in global popularity, their price has significantly decreased meaning solar energy has become much cheaper. In the past decade, the cost of solar panels has dropped from 0.79 to 0.20 $/Watt .

Solar energy is now the second cheapest energy source after onshore wind. A recent study found that it is more expensive to run 99% of existing coal plants in the US than it would be to build a new equivalent solar farm nearby instead.

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Solar Panels Are Available In A Wide Range Of Colours And Designs.

Typically, when we think of solar panels we imagine the dark blue or black panels that can be found in fields or on our rooftops. New technology now means that several companies are offering solar panels in a wide range of colours and designs, with minimal impact on their efficiency.

It may seem trivial, but having control over a solar panel’s appearance provides more potential applications. For example, we are now starting to see buildings with solar panel facades that blend seamlessly into their design. This not only provides more green energy to the buildings, but also adds visual appeal.

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Solar Panels Still Work During Cloudy Weather.

The way that solar panels work means that they are impacted by cloudy weather - but it is not as drastic as you may think.

Solar panels work by absorbing photons of visible light and converting them into useable electricity. This means that as long as there is enough light to allow you to see outside, there is enough light for solar panels to generate electricity. Clouds reduce how much solar energy reaches the solar panel, but they do not completely stop it.

A day with nearly 100% cloud coverage generates roughly half of the energy generated during a clear day.

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Solar Energy Could Be Harnessed In Space And Sent Back To Earth.

MAPLE (Microwave Array for Power-transfer Low-orbit Experiment) is a space-borne prototype that has demonstrated its ability to wirelessly transmit detectable power harnessed from the sun back to Earth.

Developed by Caltech, MAPLE was launched into orbit as part of a larger experiment to test the efficiency, durability, and function of different solar cells in space. Whilst there, it was successfully able to transmit harnessed solar energy towards Earth for the first time – providing new options for energy generation in the future.

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Solar Panels Are Compatible With Agriculture.

One concern people raise over the installation of solar farms is the amount of land they require. In reality, solar panels are often installed on land unsuitable for farming, making use of otherwise unusable space.

Additionally, when solar panels are installed on usable farmland, they can provide numerous benefits. Solar panels are being used in a new industry called agrivoltaics, where crops are grown between the rows of panels. The shade from the panels reduces the amount of water needed during the growing process and is beneficial to many leafy green plants.

Interestingly, livestock kept in fields with solar panels are also shown to live happier lives. Solar panels improve forage quality, reduce water demand, and provide shaded areas for the animals to rest.

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Solar Panels Could Be Integrated In Roads.

The idea of energy-generating highways has been around for a while, but in recent years some companies have tried to make them a reality.

Solar roads are drivable highways that are made of durable solar panels, designed to generate electricity during the day. The idea is that the energy generated could be used to power a number of smart features:

• Smart LED lighting along the highways that can alert drivers to upcoming dangers and light up dark roads at night.
• Inductive charging for electric vehicles meaning that cars could be charged whilst driving.
• Heating elements that can quickly melt ice and snow during winter months.

There is still a long way to go before we could see this technology implemented on a large scale. A major trial in 2016 by WattWay saw a 1km solar road installed in Normandy, France. Although the system worked, the amount of energy generated was lower than predicted and the road became damaged too quickly under normal traffic conditions. The road was decommissioned in 2019.

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Solar Is The Fastest Growing Energy Sector.

Solar is undeniably the fastest growing sector in the energy industry, driven by rapid technological developments and ambitious zero-emission targets.

The number of jobs associated with solar energy has doubled in the past decade, with an estimated 5 million people now working in the industry globally. This accounts for more than a third of the total renewable energy workforce.

The solar energy sector is also leading the energy industry in gender equality, with 40% of jobs being held by women.