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

Ecosia

By
We all need to do something to save our planet: it is no use just leaving it to Greta Thunberg! She is very inspirational, yes, but she can only do so much. She isn't superhuman! The climate crisis is up to us; up to you. We all have to get stuck in. Research, learn, discover and most importantly: never give up! The world's animals need us. The world's trees need us and a simple way to do this is to switch to Ecosia. Ecosia is a search engine but it plants trees while you search the web. Okay, it doesn't have as many websites as google so you may want to have google as a backup but it plants trees: this is your opportunity to make a simple change. Just google Ecosia and search to plant trees. Make a difference. Image: This image  is owned by  Binyamin Mellish on  pexels.com .
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

Green Pets: meet two new additions to my house plant family

By
Hi Everyone! This is a bit of a shorter post today but I have two new house plants! I love my new green pets so today I wanted to share them with you! >Neither of them have names yet so any suggestions welcome and appreciated :) Pilea: I love my new Pilea! My mum has one and managed to grow another from it and gave it to me. I also put it in a pot which originally had my Aloe Vera in it, but it grew too big! Anyway, I'm so glad my Pilea could find a home in it! I love the way this plant looks and it makes me very happy to look at!  I actually don't know the name of the second one - I will insert it when I have found it!  I got this one from my aunt in France who has one and made a cutting for me. I'm not sure if it'll survive but we'll see - it's certainly well-travelled! I'm not giving up hope yet and even if it doesn't make it she said she could cut me a new one! I will update on this ...
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

Private jets - are they really as bad as people say?

By
Hello everyone, On social media, they will be an uproar every few months because some celebrity used a private jet to get somewhere. Today, I'll be talking about whether these flights really are as bad as they seem or whether social media is just making a big deal out of nothing. Emissions: private jets vs public flights Private jets are 5 to 15 times worse than commercial flights per passenger. Also, private flights are normally not 4 hours long, some of them are only 20 to 30 minutes! These flights are worse because taking off and landing emit more greenhouse gases . With a flight that's only 20 or so minutes, you've only got 10 minutes at the most where you're actually flying 'normally'. So when it comes to emissions, private jets are very bad for the environment. Morals You can't talk about private jets without talking about the morals involved. The first moral problem with private jets is the people who use them....
Post a Comment
Read more

Green Pets: Introducing my new house plant!

By
Hi Everyone! As you can tell by the title of this post, I got a new houseplant! It was a Christmas present but I chose it in a really sweet plant shop near me. It is called a Mind Your Own Business, in more technical terms a Soleirolia. It's latin name is Soleirolia soleirolii. Introducing Mr Darcy! I named it Mr Darcy because I love Pride and Prejudice and I thought it appropriate! It needs to have constantly moist soil and has to be watered by being put in a bowl of water, rather than with a jug. This is because it will get a hole where the water has gone down as it is quite delicate and the leaves are very fine. It's important to look up how much water your house plant needs and get tips from experts to help your plant to thrive. I talked to the lady in the shop when we were buying it and she told me about how to look after it. It is joining my two other house pla...
Post a Comment
Read more

Turning waste into valuables

By
Hi, So this post was requested on Twitter after our September Top Tips about recycling . Today we will be talking about how to turn complete waste into something reasonably valuable. This is basically a form of upcycling but to a more extreme level. 1. Ecobricks So, almost a year ago we did a post about ecobricks , but they are such a good example of turning waste into valuables that we decided to put it here anyway. Ecobricks are a building material made from plastic. The waste plastic is washed and then compacted into a clean plastic bottle (also waste). The bottle becomes very hard and durable. Multiple bottles can then be used as bricks and cemented together. The 'bricks' are strong and do not decompose. For more info, read our post where we go into more detail. 2. Metals Although this may seem like something not worth the time. When you separate the metals in waste (for example an old car), you can get usable metal out ...
Post a Comment
Read more

10 animals on the edge of extinction you didn't know about no.4 - Sumatran elephant

By
Hello everyone, This is the 4th post in our '10 animals on the edge of extinction you didn't know about'. Today we are going to be talking about Sumatran elephants. You've probably all heard about Sumatran tigers, which are also on the edge of extinction, but Sumatran elephants are much less well-known. Characteristics Sumatran elephants live for around 70 years and grow 2 - 3.2m tall. They weigh 2 000 to 4 000 kg and are the smallest subspecies of Asian Elephant. The males have tusks, however, these don't grow as long as their African counterparts. The females also have tusks but these are normally so small, that they are hidden under the upper lip. Sumatran elephants are herbivores, eating bark, bananas, young fresh leaves and occasionally various wild herbs. Social lives Elephants are very social and live in herds of 20 - 35 individuals. These herds are led by a dominant female. Males leave when reach adolescence, either willi...
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