Energy comparison: solar (PV) panels

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.

We have already mentioned the fact that we do not have the needed resources to produce that many solar panels.
We do not have the infrastructure to build a massive solar field.
Such a project would produce massive greenhouse gas emissions during production.
As already mentioned, we can't effienciety store solar energy and transporting it to another part of the world would be difficult.
We would have to replace the solar panels after about 25 years, which would cause massive amounts of waste.
It would cost trillions of dollars.
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.
A power cable from the sahara to the rest of the world would have at least a 20% power loss.
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.
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.
Due to point 9. hurricanes and storms would rampage the Americas more frequently.
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:

https://www.energy.gov/eere/solar/how-does-solar-work
https://www.energy.gov/eere/solar/solar-photovoltaic-technology-basics https://www.energy.gov/eere/solar/solar-photovoltaic-cell-basics
https://www.solar.com/learn/how-solar-panels-absorb-and-store-energy/
https://www.solarsystemaustralia.com.au/how-efficient-are-solar-batteries/
https://solvoltaics.com/energy-make-solar-panel/
https://solarpowerfocus.com/disadvantages-of-solar-energy/
https://earthfirst.org.uk/environmental-impact-of-solar-panels/
https://medium.com/predict/why-dont-we-cover-the-sharah-in-solar-panels-3692a5bf89bd
https://www.theguardian.com/science/2023/sep/17/tim-peake-backs-idea-for-solar-farms-in-space-as-costs-fall
https://www.sciencedaily.com/releases/2023/09/230920111217.htm

Image:

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

Comments

April Top Tips: ten tips for environmentally friendly travel

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...

Animals 21-25 in our '50 incredible animals' series

Hi Everyone! Here are the next five animals in our current series! We hope you learn something from this. 21. Stick insect Stick insects are masters of disguise. They look like twigs or leaves. This strange appearance makes them hard to spot when stationary. Stick insects are herbivores, feeding on leaves, and can live for up to three years. Their habitat includes most tropical and subtropical regions, but there are a few species that live in temperate areas as well. There are roughly 3 000 different stick insect species! Not much more is known about them, because they are difficult to find. The two main threats to their populations are the pet trade and people killing them so as to frame their carcasses, like butterflies. Their conservation status ranges from critically endangered to least concern - so basically every category that is on the list! 22. Glass frog The glass frog is, well, see through. You can literally ...

29.11.2020 Animal Of The Week: Jaguar

Hello, Today (29th November) is world Jaguar day so this week our animal is the Jaguar. The Jaguar is an animal I know pretty much nothing about so I am going to learn a lot too! Jaguars (panthera onca) live for 12 - 15 years. Their heads and bodies are 150-180cm long and their tails are 70-90cm long! They weigh 45 - 110 kg. Habitat Jaguars live primarily in the Amazon Basin, though they can be found in smaller numbers in Central America. They once lived everywhere from central Argentina up to the southwestern United States but since the 1880s they have lost over half of their territory. They are mainly found in tropical rainforests but can live in savannas and grasslands. Diet They eat fish and turtles as they are actually quite competent swimmers as well as deer, iguanas, birds and monkeys; they will eat almost anything! Are they endangered? Jaguars are classed as near endangered and face several threats. South and Central Americ...

Eco Bricks -Taking Upcycling to another level

Eco Bricks Are they the key to the world's plastic pollution problem? Or at least a helpful factor if they became a permanent solution with no disadvantages? But what are they anyway? How are they useful? And how can individuals help every day? Here are some tips for everyone wanting to save plastic and help the earth. Eco bricks are plastic bottles, filled densely with hard and soft plastic that make a bottle so hard and sturdy that they could be used to build houses. Which in fact, they are. To make an Eco-Brick, you need a clean and dry plastic bottle, a long stick and lots of plastic. All plastic must be clean and dry, so it should be washed and dried or hung up to dry before usage. Now the bottle can be filled with layers of soft and hard plastic alternately that is pushed down with the stick to fill every corner of the bottle. That is done until the Eco-Brick is entirely stuffed with plastic and hard as a brick. The advan...

February 2021 Factfile - a bit of news from the last month and more!

Hi Everyone! Welcome to February's factfile! We are very sorry that we have not posted very much so far in 2021 but we are going to hopefully make up for it in the spring. News: Source- BBC Newsround The great yellow bumblebee has been spotted in Scotland! They used to be common in the UK but their population declined by about 80% in the last century. The find is a spark of hope as it is currently endangered. This is thought to be because of a decline in natural flower meadows and a boost in farming. The team of conservationists that found it were thrilled and when we heard about it we wanted to share it with you in case you hadn't heard! Source- Guardian In the 1840s a bird was caught in the East Indies. It had never been seen before and Charles Lucien Bonaparte (Napoleon's nephew) named it the black-browed babbler. The species wasn't seen again, so the only proof that it had ever existed was a stuffed specimen. ...

Green Pets: meet my house plants

Hi Everyone! Today I am writing a very exciting post as this is the first Green Pets post. Thank you so much to the person who suggested the name! Today I am showing you my house plants. I have two house plants but I hope to grow my collection! Vera, aloe vera (aloe barbadensis miller) I was actually very kindly gifted this for by birthday from a friend! It came in this beautiful pot with all these bees, that I just love! She suggested the name Vera and it's not very original but I still went with it because, why not? Our plant of the month for August ( click here to view ) was actually the Aloe Vera and it partly inspired me to start this series. I love having it in my room and I'm really trying to keep it alive, so far it's grown a lot since I got it! Bronausten, indoor fern (Nephrolepis exaltata) This plant is named after the Bronte sisters and Jane Austen, two of my favourite authors. It is an indoor fern and I l...

Green Pets: Introducing my new house plant!

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...

Coral reefs

Hello! We would love to introduce you to the topic of coral reefs and especially coral reef bleaching, as it is a greatly ignored but certainly significant topic. Have fun! 5 coral reef facts 1. The Great Barrier Reef is the largest living structure on the planet and is 2300 km long! 2. Less than 0.1% of the world's ocean surface is covered in coral reefs. 3. At least 25% of all marine animals live there. 4. Coral reefs are often known as the rainforests of the ocean. 5. In 1 square kilometre of coral reef, up to 35 tons of fish can be 'produced'. The 5 biggest coral reefs in the world 1. Great Barrier Reef (near Australia) 2. Red Sea Coral Reef (near Egypt, Israel and Djibouti) 3. New Caledonia Reef (Pacific Ocean near New Caledonia) 4. The Mesoamerican Barrier Reef (near Mexico, Belize, Guatemala and Honduras) 5. Florida Reef (Atlantic Ocean/Gulf of Mexico near Florida) What is coral? Coral is actually made up of small anim...

November Top Tips | sustainable activities and hobbies

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...

The Responsible Traveller by Karen Edwards || a practical guide to reducing your environmental and social impact // BOOK REVIEW

HI Everyone! Our January monthly post was a zero-waste challenge, but as we explained in our 2023 wrap up , this year we will be alternating a monthly challenge with a book review, of course related to the environment. This week, I'm going to share a recommendation for a fantastic book, all about how you can travel more sustainably and responsibly. I absolutely love travelling, but I'm also very aware of the impact it has on the world, and I am very keen to learn more about how I can further reduce my impact. That's why I bought this book around a year ago, and I've really enjoyed reading it and learning from it. This is a practical, small-format guide, sharing both basic information about the climate crisis and the impact of various travel activities, and how you can do your bit. It shares specific journeys that are more environmentally friendly options, for example long distance train journeys such as The Alaskan Railroad with its stunning alpine forests and wide ar...

Green World

Search This Blog