Solar power is the fastest growing renewable energy globally and one of the most cost-effective too. Yet a lot is still unknown about the technology and how it produces electricity out of sunlight. Here we delve into 18 little-known facts about solar panels.
Did You Know…
1. ...when the first clean energy was produced by sun rays?
The photovoltaic effect of producing electricity from sunlight was first observed in 1839 by French physicist Edmond Becquerel. In 1876, Adams and Day, two British researchers, observed the photovoltaic effect in solid selenium. It wasn’t till 1954 that the scientists Pearson, Chapin, and Fuller discovered the solar cell. The original solar cell was only 4.5% efficient but was further optimised to 6% a few months later.
2. ...due to innovation, solar panels efficiency are rapidly improving?
Solar panels are now more than 20% efficient, thanks to innovation in the solar power industry. Just over 5 years ago the most efficient solar panel on the market was 17.8%. Today solar panels have an efficiency range of 20 to 23%! The two leading brands when it comes efficiency are SunPower and Panasonic.
3. ...airplanes can fly on solar energy alone?
Airplanes have flown around the world entirely on solar power, yes you heard this correctly! In 2016, Bertrand Piccard, a Swiss pilot and explorer, flew around the world in a solar-powered plane. The Solar Impulse II used only solar power to circumnavigate the earth.
4. ...where the largest solar panel plant in the world is?
The largest solar power plant in the world is located in India, Kamuthi, Tamil Nadu. The plant covers an area of 10 square kilometres and has a total installed capacity of 648 MW. The solar power plant took eight months to construct. The solar panels are cleaned daily by a robot that is powered by solar power. The plant produces enough clean energy to power 150 000 homes!
5. ...how much space would be required to power the whole earth with solar power?
Now this is a pretty cool fact: to power the entire earth on solar power, we would require 307 384 square kilometres of space for the solar panels themselves. The earth covers 91,72 million square kilometres, so there’s more than enough space to power the planet on solar power alone!
6. ...how much solar power capacity is expected to be installed by the year 2025?
Solar power is the most popular renewable energy source in the world. It’s also one of the cleanest and most reliable sources of renewable energy. Total installed capacity is expected to reach 969 GW by 2025. Solar power is also now the cheapest form of renewable energy with a median national installed cost of AU$1.78 per watt.
7. ...the efficiency of the world’s most efficient solar cell?
Scientists have recently developed the world’s most efficient solar cell, with an efficiency ratio of 44.5%. The solar cell is able to capture and convert a much higher degree of the sunlight’s overall light spectrum.
The solar cell uses gallium antimonide (GaSb) substrates, which are usually reserved for infrared lasers and photodetectors, in order to absorb every part of the direct sunlight. The solar cell used a unique printing process that allows a much greater degree of precision.
The technology is still some way off reaching commercial production. However, using solar panels with this efficiency ratio means half the amount of space would be required to produce the same amount of energy as the systems in place today due to their greater efficiency.
8. ...how solar panels produce electricity?
Solar cells produce electricity by causing a reaction between photons and electrons at the atomic scale. Photons, which are rays of light, collide with electrons, and the electrons get catapulted loose. Then, the electrons are captured and channelled into usable electricity. Solar cells capture certain types of wavelengths in the sun’s light spectrum and convert this into electricity.
9. ...how much the cost of solar power has fallen since 1977?
10. ...how much solar radiation penetrates the earth?
11. ...how to fully benefit from solar power, even at night?
One of the disadvantages to solar power is that it doesn’t produce any electricity at night. However, by using a battery system you can store excess power for later use when it’s required. An alternative to this is to take advantage of net metering or feed-in tariffs (depending on what is possible in your state) and feed excess power back into the grid.
12. ...how the sun is powered?
Solar energy is actually nuclear fusion, well sort of! Nuclear fusion is where two or more atomic nuclei come close enough to form one or more different atomic nuclei and subatomic particles (neutrons or protons). The result gives off heat as energy, and the same process happens in the sun. That same energy that reaches planet earth is used by solar panels to produce electricity.
13. ...how much solar energy hits the earth each day and how much electricity the whole planet uses?
Each hour, 430 quintillion Joules of solar energy hit the Earth. Now who would have thought such a numerical value actually exists!
To put this into perspective, the earth's total energy consumption for one year is currently around 410 quintillion Joules.
To put it another way, every hour we receive more than enough solar energy to power the world for a year.
14. ...how much of a solar panel can be recycled?
Some of the materials used in manufacturing of solar panels are toxic and if solar panel recycling processes weren’t in place, 60 million tons of PV panels would be lying in landfills by the year 2050—these figures are for the EU alone. Luckily, 96% of a solar panel can be recycled.
15. ...Australian solar panel waste predictions?
The amount of solar panel waste in Australia was 900 tons in 2016. This figure is expected to rise to 2 000 tons in 2020, 30 000 tons in 2030 and 300 000 tons in 2040, with a whopping 900 000 tons in 2050. Goes to show the need for solar panel recycling!
16. ...the life expectancy of a solar panel?
The life expectancy of solar panels is on average 30 years. During the lifespan of a solar panel, the output performance might decrease by 20%. However, high-quality solar panels can possibly still provide output after 30 or even 40 years!
17. ...the world's first modern solar panel is still producing electricity?
The world's first modern solar panel is still producing electricity after 60 years. The 60-year-old crystal ball-like contraption was built by a British science teacher who wanted to prove the novel idea that sunlight could be converted into electricity.
The solar contraption doesn’t produce much electricity—just 1.5 V of electricity in direct sunlight. But it’s remarkably similar to current solar panels.
18. ...solar panels have applications in space?
Spectrolab, a division of Boeing, manufacture high-efficiency solar panels for the space industry.
These solar panels are made from special materials to protect it from solar radiation and the extreme environmental conditions of space. These solar panels also have an efficiency ratio of 31%!
The solar cells use multi-junction technology. Multi-junction cells use multiple p-n junctions made of different semiconductor materials. Each material's p-n junction will produce electric current in response to different wavelengths of light. The use of multiple semi-conducting materials increases the amount of wavelengths absorbed by the panel. This improves the cell's sunlight to electrical energy conversion efficiency.
The photovoltaic effect of creating electricity out of sunlight was first discovered in 1839 and the first solar cell developed in 1954.
Since then, solar panel efficiencies have gained the upper hand from 6% to over 20% in today’s world. The highest efficiency yet to be achieved is 44%—in the lab of course!
The demand for solar power is increasing every year, with the largest solar farm producing a whopping 648 MW in India. Total installed global capacity of solar power is expected to reach 969 GW by 2025!
Solar cells work by creating electricity out of a reaction between photons (light rays) and electrons.
Up to 96% of a solar panel can be recycled. The amount of solar panels that will need to be recycled in the next few decades will reach gigantic proportions. Yet recycling of solar panels is expected to create a whole new industry!
If you want to see how much solar or battery storage could save you over the next 5 years, then take our solar saving calculator quiz below!
Or talk to an Instyle Solar expert about the best solutions for home energy storage or PV-panels.
Otherwise, head back to the solar blog to find even more great educational content.
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