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

Coral reefs

By
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...
Post a Comment
Read more

Deforestation and why it’s a problem

By
Hi everyone, Welcome back to another post. Today we’ll be talking about deforestation and its impacts on our earth. Deforestation, the widespread clearance of natural forests, has been happening for thousands of years. One example is Western Europe, where, two millennia ago, 80% of the land was cloaked in dense forest cover. However, over time, a significant portion of this green expanse was sacrificed to create room for crops, livestock grazing, and as a source of fuel and building materials. Presently, a mere 34% of Western Europe retains its woodland. Today, the tropics deal with the brunt of deforestation. Activities such as mining, agriculture, road construction, and the establishment of vast cattle ranches drive the mass clearance of tropical rainforests. This results in the release of huge amounts of carbon dioxide into the atmosphere, exacerbating the global climate crisis. The consequences come in two waves: first, the reduced number of...
Post a Comment
Read more

The life of ... a koala

By
Hello everyone, Today we're talking about koalas. Also known as koala bears, koalas are marsupials. So they're actually not bears. Koalas, phascolarctos cinereus , are tree dwelling and probably best known for spending most of the day sleeping. They live for up to 15 years in the wild although captive koalas generally live for longer. Koalas have a stout, gray body and a cream-coloured chest. They have a broad face, small yellow eyes and big fluffy ears. In adaptation to climbing, their feet are strong and clawed. Adult individuals in South Australia weigh 14kg and are 60-84cm big. Their Eastern cousins are considerably smaller. Koalas are found in Eastern and Southern Australia, where they live in eucalyptus trees. They feed on the leaves of these eucalyptus trees, eating up to 1.3kg a day. With a body weight of up to 14kg, this means they eat just under 10% of their body weight every single day. However, the le...
Post a Comment
Read more

Photo Essay || Iceland Series (part 1)

By
Hi Everyone! I recently went on a school trip to Iceland! It was such an incredible experience (and I'm going to sound cheesy now) but it was also incredible to do it with some of my closest friends! I saw so many incredible things and learnt so much, so I couldn't resist sharing a little Iceland mini series of posts, all about Iceland, both my experiences there and what I saw, but also the way it uses geothermal energy, and the animals, natural landforms and plants that are there. Today I'm sharing some photos of my trip. These are all photos I have taken, and are also the highlights so please bear that in mind as you browse these! I hope it is interesting and inspires you to book a trip to Iceland! The blue lagoon <33 landscapes.... Lost little farmhouses a...
Post a Comment
Read more

Sir David Attenborough - an incredible naturalist

By
Hi everyone and welcome back to Green World, Today we want to talk about one of the most inspiring naturalists of our time. It is, of course, David Attenborough. Today (08.05.2021) is his 95th birthday so we seemed it fitting to publish a post about him today. Over his lifetime, David has won more than 40 awards for his work and was named among the 100 greatest Britons in 2020. David first joined the BBC in 1952 as a producer for the Talks department which looked after all non-fiction broadcasts. Since then, he has worked on lots of different programs and documentaries such as The Life Series, which was first made in 1979. More recently, he has presented Blue Planet and Blue Planet II. The latter had the most views recorded for a single program in 2017. David also gave the Royal Institution's Christmas Lecture in 1973 on The Language of the Animals. David Attenborough is still presenting documentaries to this day. He now lives in Richmo...
Post a Comment
Read more

How much do you know about rainforests? - Quiz

By
Hi everyone Today we have another quiz for you. This time it's about rainforests. Questions How much of the earth's surface is covered by rainforests?  a) 3%  b) 6% c) 12% What percentage of our oxygen do rainforests create? a) 20% b) 30% c) 50% True or False? The Amazon Basin stores 1/5 of the world's freshwater? How many plants used in cancer treatment can only be found in rainforests? a) 40% b) 50% c) 70% True or False? A raindrop can take 10 minutes to fall from the tree tops to the ground in tropical rainforests? If the Amazon rainforest were a country, it would be the a) ...largest country in the world b) ... 9th largest country in the world c) 10th largest country in the world How many of the flowers in the Austrailian rainforests are only found there? a) 70% b) 80% c) 90% True or False? ...
Post a Comment
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

06.12.2020 Animal of the week: Cheetah

By
Hello everyone, this week's post is all about cheetahs. These incredible big cats are known for their speed, but what else? Habitat and loss of it Cheetahs live and hunt in the grasslands and bushy areas of Africa and the Middle East. Once, they could be found all across Africa and Asia, now they are heading towards extinction. The loss of their natural habitats and the decline in their prey is the reason behind this massive decline. Hunting and Diet Cheetahs have excellent eyesight, which they use to spot prey during the day. They then creep up on their prey, camouflaged in the grass. Suddenly they dash for their prey. They are the fastest land animals in the world, reaching speeds of about 60 to 70 miles an hour (97 to 113 kilometres an hour). However they can only run this fast for about 15 seconds before they overheat. After that they have to catch their breath for half an hour before they can eat anything. They use this method to...
Post a Comment
Read more

Overfishing- An Introduction

By Anonymous
When writing the article on the Yangtze Finless Porpoise, I briefly touched on the topic of overfishing. Many of you have probably heard about it, and know it is a massive problem threatening our seas and their inhabitants. Overfishing is so destructive, it can kill all life in the ocean, and many of you might be part of it every day. So I read through many articles from international organisations, and they all say pretty much the same things. It's a highly complex topic, with so many things to say and do, so this is just an introduction to the broadest points. It's very interesting (and sad) but when you look into it further you realize there is actually a lot you can do! This is very important, especially for ocean lovers and seafood people. What is overfishing? By definition, overfishing is so intense fishing, people catch fish quicker than the stocks can reproduce. Leading to a massive decrease in stocks that can peak in the extinction of a s...
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