Skip to main content

Energy comparison: solar (PV) panels

Image
By
Hi everyone,

Today I'm looking into the first on a long list of energy sources: solar (PV) panels. Are they actually sustainable and could they become our main energy source in the near future? After all, enough energy from the sun reaches the earth in 90 minutes to cover the entire world's energy consumption for a whole year!

How they work

There are a couple of ways to transform energy from the sun into electricity. The one we are looking at today is solar panels also known as solar photovoltaic technology. Photovoltaic (PV) technology is the key to solar panels. A solar panel is made of many PV cells. A single PV cell will produce 1-2 watts of power. They are very thin and are normally protected by glass and/or plastics. This is the best explanation I could find (click here for the source):
When the semiconductor is exposed to light, it absorbs the light’s energy and transfers it to negatively charged particles in the material called electrons. This extra energy allows the electrons to flow through the material as an electrical current.
The electric current produced is a direct current, so a converter is added to convert it into an alternating current used in households. Some PV systems will have structures that angle the panels to face the sun for maximal energy production.

Energy storage

Solar panels themselves do not store energy. However, there are batteries for storing solar energy. They are quite expensive. Lithium-ion batteries are at least 90% efficient. That isn't terrible but you would still lose 10% of your electricity. Lead-acid batteries may be the most affordable, but they have an efficiency of 60%-80% (depending on model and brand). That's quite bad. Flow batteries, which are the newest model have 85% efficiency. So all in all, solar batteries aren't amazing and it's definitely one of the biggest problems for the industry.

Energy in production

To produce one 100-watt solar panel, you need about 200kWh (varying massively). With enough sunlight, the 100-watt solar panel would produce enough electricity to cover that in about 2 years. A solar array (multiple solar panels) has a carbon footprint about 20 times smaller than a power plant (when both produce the same amount of energy). A solar panel becomes net zero after about 4 years of being used. We're hoping that it will soon be possible to use solar panels to power the factory making solar panels. However, there would still be CO2 emissions due to transportation and maintenance.

Downsides

In 2016, 250 000 tonnes of 'solar panel waste' were generated in the whole world. Estimates say it could be 78 million tonnes in 2050. Cadmium and lead are contained in this waste and can be washed into local rivers and bodies of water, causing extreme health risks for nearby people.
As mentioned above, fossil fuels, normally coal, are needed to produce solar panels. During production, hydrofluoric acid and sodium hydroxide are used. Most of this is dumped in local bodies of water, where they release toxic substances and chemical waste. There are also allegations of a lack of the needed safety gear and regulations that protect the workers producing the solar panels.
19 different rare metals are needed for PV cells, and most of them require mining. So we cannot create endless solar panels without running out of materials.

Covering the Sahara?

Many people think we should cover the Sahara desert with solar panels. This may sound like a good idea at first. After all, it would produce enough electricity to easily power the whole world, there is plenty and as not many species live in the desert, it wouldn't destroy too much habitat. However, it is a very bad idea.
  1. We have already mentioned the fact that we do not have the needed resources to produce that many solar panels.
  2. We do not have the infrastructure to build a massive solar field.
  3. Such a project would produce massive greenhouse gas emissions during production.
  4. As already mentioned, we can't effienciety store solar energy and transporting it to another part of the world would be difficult.
  5. We would have to replace the solar panels after about 25 years, which would cause massive amounts of waste.
  6. It would cost trillions of dollars.
  7. While it is night in the Sahara, there will be no electricity production. However at this time, it is broad daylight in Australia meaning that they need electricity. As said before, the storage is not optimal.
  8. A power cable from the sahara to the rest of the world would have at least a 20% power loss.
  9. The solar panels would cool the desert, meaning plants would grow. Then it wouldn't be a desert anymore and we would be destroying more habitat.
  10. The dust and sand that the wind in the sahara picks up, fertilises the Amazon rainforest. With all those solar panels in the way, the dust wouldn't fertilise the Amazon. The amazon dying would be a catastrophy.
  11. Due to point 9. hurricanes and storms would rampage the Americas more frequently.
  12. Global oxygen levels may drop due to losing the amazon (point 10.) and the atlantic also being affected.
I could go on and on, but I think you get the point. Covering the entire Sahara and trying to power the whole world with it, is a really bad idea. However, it could be implemented on a much smaller scale to provide local populations with electricity. Morroco has the world's largest solar farm in the Sahara.



All in all, solar panels aren't great for the environment. However, the idea of using the sun's energy is actually not too bad. If the technology surrounding the production, waste and storage of solar panels could be drastically improved, then we could use solar panels as the world's main power source. We just need the technology to be efficient first. This is already in the making, hundreds of scientists world-wide are working on how to improve solar panels. There are also ideas of creating solar farms in space, which would eliminate the problem of solar farms being reliant on the weather.

Your Green World Blog Team💚


Sources:

Image: 
This image, owned by Wolfram Burner (on flickr.com) is liscensed under CC BY-NC 2.0.
Labels:

Comments

Post a Comment

Popular posts from this blog

April Top Tips: ten tips for environmentally friendly travel

By
Hi Everyone! We haven't been very present on the blog again recently but we are back today with ten top tips for environmentally friendly travel. Most forms of travel over long distances (unless you are willing to put in a lot of physical effort) use fossil fuels and are generally not good for our planet. So today we will be giving you a few tips which although won't mean that your travel is 100% planet friendly, will be a good start to doing as much as you can.  Your Green World Blog Team💚 1. Use trains and boats rather than planes where possible Planes are awful for the environment. They are, however, extremely practical and so easy to use, cheap...It's hard to avoid them! They are so quick too so you don't have to spend as much time travelling. However, they are really bad for the environment. For example, you could fly once to Edinburgh from Heathrow for the same carbon dioxide levels as driving to Edinburgh 336 times! 2. Fly...
Post a Comment
Read more

Metamorphosis

By
Hello! Today we thought it would be good to explain exactly how metamorphosis works. It's a term that we often use when talking about frogs, butterflies or other animals, but we've never actually explained what it is or how it works. What is metamorphosis? Metamorphosis is the term used to describe the changes that some animals undergo when turning into adults. It is a physical change that happens after birth/hatching. There is a brilliant quote from the website a-z animals that I just couldn't put any better:  unlike the typical subtle developments in animals, metamorphosis is dramatic. It’s controlled by a release of hormones in the cells. Mammals usually move from adolescence to adulthood and old age gradually, maintaining their form and shape. However, in metamorphosis, an animal moves through those stages and changes from one form or shape to another. How does metamorphosis work? Let's take the classic butterfly example./d...
Post a Comment
Read more

August 2021 Factfile - some news, animals and a plant

By
Welcome to our August factfile, News Bad news :( Fires in and around Athens Athens has been under siege this month, but not by any army. The forests all around the capital and in other parts of Greece and Turkey have gone up in flames. Houses have been destroyed and thousands have been evacuated. The reason is, of course, climate change . “It’s been crazy over here. Between the extreme heat and the wildfires, it feels apocalyptic,” Eleni Myrivili wrote in an email on Thursday as the army was deployed to assist firefighters. “Ash is raining down on us here in Athens.” England's lake district in peril Lake District, a popular holiday resort in the north of England, is now eroding faster as a result of climate change and an increased amount of walkers due to the pandemic. Paths that were once two meters wide are now at least 12 meters wide on some walks. Also visitors tend to walk off the path, endangering local wildlife. With...
Post a Comment
Read more

Announcement: Galápagos Islands

By
Post a Comment
Read more

October Top tips | homemade presents

By
Hi everyone, So today we're going to talk about sustainable homemade presents. If you start now, then some of these would make amazing Christmas presents. 1. Knitting, crochet, embroidery & more yarn items You can make some incredible presents by knitting or crocheting with wool or thick yarn. All you need are needles and wool/yarn. Wool can be expensive if you want good quality so check out this post about making your own yarn out a t-shirt! With thinner yarn you could make some amazing thing through embroidery. Here are some project ideas: Scarfs  Socks Blankets Jumpers Pouch Dishcloths Table mat Headband Fingerless gloves Keychains Friendship bracelets Wall decorations Handles for hot pots and pans Figurines Bag designs 2. Origami Origami is an amazing way to show someone that you put time into what you made. You can use paper of any size, colour or pattern. Here are some ideas: Swans ...
Post a Comment
Read more

Green Pets || easy house plants to get you started // best house plants for beginners

By
Hi Everyone! Today I wanted to talk to you about some easy house plants you could look after to get you started on your green pets journey. These are plants that are easy to look after and that I recommend for an introduction into caring for house plants. If you are a beginner or want to look after some plants, then this is the post for you! 1. Cacti - moon cactus I don't actually have a cactus, but they are the obvious place to start. They need little water and thrive in warm conditions; they are described as "low maintenance". I have done some research and it looks like the moon cactus (Gymnocalycium mihanovichii) is the best one in terms of not being too fussy with needing minimal water and tolerates lower light levels. I would like a cactus at some point, but if you are just starting out wanting to care for some house plants, then this is the one to start with! 2. Aloe Vera One of my first house plants, this is one that is rela...
Post a Comment
Read more

Announcement: Animal of the week

By
3 comments
Read more

Animals 36-40 in our '50 incredible animals' series

By
Hi, As you probably noticed, we took a break from this series, mostly due to having just too much to do. But we're back now with the last three posts. 36. The Pinocchio frog The Pinocchio frog can be found in the Foja Mountains in Indonesia. They mainly eat insects, although little is known about them. They are named because the males have a spike on their noses. They were only discovered in 2008, and this was completely by accident! It remained unnamed scientifically until over ten years later when it was given the name " Litoria pinocchio " . There is very little information about them but Wikipedia states that "the male Pinocchio frog inflates its nose when calling, and the nose decreases in size when the frog is calm and quiet," which I think is hilarious and so interesting! 37. Snub-nosed monkey Especially noticeable due to their curious looks, the snub-nosed monkeys can be found in the forests of central China and northern...
Post a Comment
Read more

06.09.2020 Animal Of the Week: Seven-spotted Ladybird

By
Hello Everyone, Welcome to this week's animal of the week post. This time about the ladybird, and personally I can't wait to find out more about these creatures. Enjoy! Which ladybird we are investigating today? Today, I am telling you about the seven-spotted ladybird (Coccinella septempunctata), which is the most common ladybird in Europe. Other species include the Two Spot Ladybird and other uncommon ladybirds such as the 16 Spot and other peculiar types. Habitat The seven-spotted ladybird lives in a variety of habitats such as meadows, gardens and hedgerows. They can also be found on farmland, especially with crops such as alfalfa, clover and wheat and corn before it grows too tall. Diet The seven-spotted ladybird feeds on a range of aphid species. This is why they are often referred to as a gardener's best friend as they eat these creatures who can damage plants. They can also eat white flies and anything else that is soft-bo...
Post a Comment
Read more

10 animals on the edge of extinction you didn't know about no. 9 - South Island takahē

By
Hello Today we’re talking about the South Island takahē, porphyrio hochstetteri . They are flightless birds, endemic to New Zealand. Takahē are brightly coloured and weigh 2.3-3.8 kg. They have red legs and a large red beak. Their feathers are coloured blue and green. They have wings, but these are only used during courtship or rivalry displays. They are territorial, with one family’s territory reaching anywhere from 4 ha to 100 ha (0,04-1km^2). Pairs will live in the same territory each year. They breed once a year and will raise 1-3 chicks (normally 2) each year.  Both parents raise the chicks together.  In the wild, takahē live in native grasslands and have a lifespan of 16-18 years. If snow covers the ground then they will move into nearby forests. They eat tussock grasses, sedges and sometimes rushes. But they are opportunists, so they will occasionally go for insects or even ducklings and...
Post a Comment
Read more