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 TeamšŸ’š


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

October 2021 Factfile | news, animals and more!

By
Hello, October is over and November is here - let's hope it's a cosy month full of stunning Autumn colours and beautiful rainy days! News Good news Judge postpones wolf hunt in Wisconsin Every year in Wisconsin there is a wolf hunt in autumn. But this year, something amazing happened: A judge halted the season. For years there has been a dispute, on one side environmentalists, and on the other hunters and farmers. The farmers claim that wolves destroy their crops and that killing them is the only solution. Environmentalists argue that wolf populations are too weak and that the animals shouldn't be killed. Let's hope that this is the first step toward stopping the wolf hunt altogether. Bad news Pacific islands are disappearing For many of us, the threat of climate change feels distant. But for the people of the Pacific islands, the terror is all too real. These are their homes, and they are rapidly becoming submerged b...
Post a Comment
Read more

The limits of the Earth - the planetary boundary model

By
Hi everyone, So today we're talking about a model that was introduced in 2009 and has offered a new perspective to thinking about environmental issues. The planetary boundary model has 9 boundaries, each has a safe zone. Once the safe zone is exceeded, the stable conditions on our planet are considered at risk, and there can be severe and possibly irreversible changes. The nine boundaries are considered separate however, they greatly affect each other. Novel Entities describes the introduction and accumulation of man-made novel chemical compounds. These include pesticides, nuclear waste and microplastics. Stratospheric Ozone Depletion refers to the depletion of the ozone layer which was a major problem in the 90s. Atmospheric Aerosol Loading is air particle pollution.  Ocean Acidification is self-explanatory. The boundary Biochemical Flows is composed of two separate boundaries; nitrogen and phosphorus. Both of the ele...
Post a Comment
Read more

2022 in a nutshell - stats, opinions, updates and goals

By
Happy New Year! We hope you are all enjoying the last day of 2022 (or whatever day you are reading this on). Today we are going to be looking back on 2022 and setting goals for 2023.  2022 in stats 48 posts 3191 views most viewed post: The Amazon Rainforest part 4 best posting month: October worst posting month: March 166% increase in views compared to last year How was it for us? Elsie: I really enjoyed this year from about May. After some behind-the-scenes changes, we managed to get so many more posts out and writing them felt a lot less stressful. I also really enjoyed the experience of having a guest blogger (click here ). My favourite posts to write were the Pride Month post and the ' how trees communicate ' post. They both required quite a bit of background research, which was fun and interesting. Freya: Although I haven't written on here as much as I was hoping this year, I have loved still being a part of this blog ...
Post a Comment
Read more

16.08.2020 Animal of the week: Elephant

By
Hello. On the 12th of August it was International Elephant Day, so we decided that this week's post should be about elephants. Elephants are the largest living land mammals. There are three types of elephant; the African bush elephant; the African forest elephant and the Asian elephant. African elephants have larger ears, whereas Asian elephants have smaller ears. Elephants use their trunks to breath, bring food and drink to their mouths and to grasp objects. Elephants' legs are like pillars. They carry the Elephant's massive weight. African bush elephants weigh 6000kg, Asian elephants weigh 4000kg and African forest elephants weigh 2700kg. Basically, they are very heavy.Elephants eat grasses, small plants, bushes, fruit, twigs, tree bark, and roots. Elephants can live up to 70 years old in the wild. They communicate by sight, touch and smell. Sadly, these wonderful mammals are in danger. African elephants are listed as vulne...
Post a Comment
Read more

Jane Goodall

By
Born: 1934 When Jane was a little girl, she loved climbing trees and reading books. She dreamed that she could go to Africa and see the wild animals there. So Jane flew to Tanzania determined to study chimpanzees in their natural habitat. When she first arrived, none of the chimpanzees would let her get near them. They would always run away at first sight. Jane kept coming back until they let her come closer. However, Jane wanted to become friends with the chimpanzees.  So she started the "banana club" which meant that she would share bananas with them every time she visited the chimpanzees.  She discovered that chimpanzees have rituals, that they use tools, that their language comprises at least twenty sounds and that they are not vegetarians. Once she rescued an injured chimpanzee and nursed it back to health. When she released it back into the wild, the chimpanzee turned around and hugged her as if to say, "thank you and goodby...
Post a Comment
Read more

November Top Tips | sustainable activities and hobbies

By
Hello everyone, So this week, we are going to be talking about sustainable free time activities. This area can quite big when it comes to environmental impact, so here are some things that you can do in your free time, that are more sustainable. 1. Reading So reading is one of our favourite things to do. However, books are made of paper and the paper industry isn't great. Some ways you can get around this is by reading online (for example, on a kindle), or through borrowing books from a library or using book boxes. If there aren't any in your area then at least try to support independent bookshops! 2. Running If you love being active then this one is for you. Running is probably one of the most sustainable forms of sport. All you need are some running shoes and somewhere to run. There is obviously more high-tech gear but that isn't really necessary if it's just a hobby. 3. Gardening If you've got a small area of land o...
2 comments
Read more

Maldives - the direct impacts of climate change

By
Welcome back, Today we’re looking at the direct impacts of the climate crisis . The main reason why people don’t believe in climate change is that they can’t see it with their own eyes. So, we’re going to have a look at the Maldives where the effects of climate change become more obvious with every passing year. Maldives The full name of the Maldives is The Republic of the Maldives. It is an independent country made up of about 1 200 islands in the North Indian Ocean. The northernmost island is situated 370 miles away from the mainland (India). The islands are actually the tips of an ancient volcanic mountain range that is now almost completely submerged. In fact, the highest point is 1.8m-2.4m above sea level with the average elevation being 1m above sea level. The islands have a large tourism industry, due to the stunning nature found on and around the islands. 500 000 - 1 500 000 tourists visit the islands each year. This is mainly 'nature to...
Post a Comment
Read more

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 TeamšŸ’š 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

Hummingbirds

By
Hello, Today, we're talking about an amazing group of birds that are known for their colours and the speed they beat their wings. That's right: hummingbirds! General Hummingbirds live in North and South America. They are some of the smallest and most colourful birds in the world. There are about 330 different kinds. Their name comes from the humming sound that their wings make. They eat nectar and insects using their long bills. Some species migrate during the winter. Flight The wings of a hummingbird beat so fast that the hummingbird can hover in one place and can fly forwards, backwards or sideways. Small hummingbirds beat their wings about 70-80 times per second. During courtship displays or when chasing rivals, their wings can beat up to 200 times per second. Feeding Hummingbirds eat the nectar from the insides of flowers. They hover in front of a flower and put their long and slender bills inside to suck up the nectar. This prov...
Post a Comment
Read more

Animals 31-35 in our '50 incredible animals' series

By
Hi Everyone! Welcome back to our blog, today we are sharing another 5 incredible animals. This is part of a series to celebrate our 50th blog post, all about unusual animals! Enjoy! 31. Pangolins These creatures are often mistaken for reptiles but they are in fact mammals. They are covered in scales and use them to defend themselves because similar to a hedgehog, they curl up into a ball. They eat ants, termites and larvae. They eat using their tongue, which is very long- sometimes even longer than their body! Sadly, Pangolins are in high demand as their meat is considered a delicacy their scales are used in traditional folk remedies, which means that there is an illegal trade. Luckily, there have been many initiatives put in place to help these animals by WWF and similar organisations. 32. Macropinna Microstoma This is a species of fish that live at about 600m below sea level. They hang nearly motionless in the water and have a very unusual...
Post a Comment
Read more