Skip to main content

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.
  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.

Comments

Popular posts from this blog

January Top Tips // 5 ways you can individually tackle climate change

Hi Everyone! This is the first of our new monthly posts for 2022! We will be sharing top tips every month, near the beginning, for things you can do during that month for the better. It's almost like a whole year of new year's resolutions (though let's hope they are achieved)! In these posts, we aren't just going to talk about climate change , of course, there will also be posts about animals , plants, habitats, plastic pollution and so much more! They will not be huge tips though, they won't demand too much of you (usually!). We need rebellions and people in the public eye spreading the word of course but we also need people like you, who can just do their bit. So, welcome to our top tips posts! We all know that we need to come together to fight the climate crisis, but we don't seem to be doing that right now. So here are our top tips for ways you can individually tackle climate change, even if this means simply spreading ...

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...

16.08.2020 Animal of the week: Elephant

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...

August 2021 Factfile - some news, animals and a plant

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...

The life of ... a koala

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...

2023 on Green World: the stats, our reflections & more || wrap up

Hi, Welcome back to Green World! This year has been amazing for our blog, so today we wanted to share some stats, personal reflections from each of the editors and some important information for 2024! 2023 in stats 52 posts 86 463 views most viewed post: Geothermal and Hydropower Energy in Iceland || Iceland Series (part 2) best posting month: August worst posting month: January 2610% increase in views compared to last year! How was it for us? Elsie: This year has been an incredible experience for me. I'm so grateful for all of your support and have loved writing weekly posts on topics that mean so much to me. My favourite post to write was National Parks post, it made me want to travel to all those amazing places. I've also found writing the energy comparison series really interesting because they required a lot of background knowledge and research and made me think more deeply about the complex topic of electricity production. I can't wait to see what 2024 brings us. Fr...

Maldives - the direct impacts of climate change

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...

January 2021 Factfile - a bit of news from the past month and more!

Hi Everyone! Welcome to the first monthly fact file! We are going to share a news article from last month as well as animals and more! News You might have heard that the UK has authorised the use of a pesticide harmful to bees. It has been authorised for use on sugar beet with their excuse being to do with the virus yellows disease. But bees are in serious decline and this is not going to help. It is authorised for emergency use and only in specific conditions but, in our eyes, that doesn't make it okay. Farmers need bees to pollinate crops and now they are killing them with a horrible pesticide. What do you think? We would love your opinions below! For more information on bees in our honey bee post click  here . We have also found an article about some Indonesian monkeys from the island of Bali who steal anything expensive, that tourists have because they know they will get a reward! They know which items have the most value and wi...

June Top Tips | Fast Fashion and Consumerism

Happy June everyone! This month you'll get introduced to the topic of fast fashion. It is a big thing, not only because of environmental reasons but also touches on topics such as child labour and exploitation. We know this sounds pretty grave once again, but here is some good news (surprise, surprise!): You can do something! Read on to learn about what fast fashion is, where the problems are and what you can do better. 1) What is fast fashion?! Fast fashion is a term for the ever-changing demand and supply loop of the clothing industry. Every season people want to wear different things, and different clothes are in style. That leads to people buying clothes, wearing them as long as everyone else thinks they're great and then jumping to the next wave of clothes. The demand of the masses changes quickly and the clothing industry has to react just a step ahead of them to make money. The goal is to produce the wanted clothes as quickly, as chea...

Evolution

Hi, So today, I am going to talk about evolution. We have mentioned this before in our Galapagos Ecosystem series but we’ve never gone over exactly what it is. So before Charles Darwin thought of his theory of evolution, the majority of people in Europe thought that all species were unrelated and that humans were not related to animals. This was mostly based on Christianity. Darwin studied hundreds of different species and on the Galápagos Islands , he first started to form his theory of evolution. Darwin's theory of evolution by natural selection, as it was later called, is best explained by the example of the giraffe. Let's assume that giraffes have short necks (as they did many centuries ago). Now a mother has two children. By chance, one has a slightly longer neck. This is a coincidence. As the giraffes feed on the lower leaves of the trees, these slower disappear. There aren't enough leaves for the giraffes. Thus the giraffe wi...