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

Greta Thunberg's Speech at the UN Climate Action Summit 2019

By
Hi Everyone! I thought I would share the transcript of Greta Thunberg's inspiring speech from the UN Climate Action Summit. The phrase we remember is 'How dare you!'. But what did she really want us to take away from it? She wanted us to act, so watch the video using the link below and take action because the world isn't just going to heal itself. Greta Thunberg's speech at the UN Climate Action Summit video "My message is that we'll be watching you. This is all wrong. I shouldn't be up here. I should be back in school on the other side of the ocean. Yet you all come to us young people for hope. How dare you! You have stolen my dreams and my childhood with your empty words. And yet I'm one of the lucky ones. People are suffering. People are dying. Entire ecosystems are collapsing. We are in the beginning of a mass extinction, and all you can talk about is money and fairy tales of eternal economic g...
1 comment
Read more

Discussion || Should Everyone Switch To Electric Cars?

By
Hi Everyone! Thank you so much for joining me today, as I hop on the blog to discuss whether everyone switching to electric cars would really help the environment. In other words, should everyone switch to electric cars? This is the first part of a two-part series, discussing electric cars, so stay tuned for part two!! I would like to start this post by stating that I am by no means an expert. This is knowledge I have from my own experience, and from research I have done. If anything is incorrect please take it as it is and accept that this is a discussion and I am taking on board all opinions from reliable sources on this complex topic. Electric cars are a huge topic when it comes to sustainability and "saving our planet". There is no debating the fact that electric cars are better for the environment than diesel or petrol once they are on the road. But the production of them is often very polluting, with one study show...
2 comments
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

Linking climate change and inequality - 'The Great Carbon Divide'

By
Hey everyone, Have you heard of 'The great carbon divide‘? It is often referred to as the 'carbon footprint gap' or the 'emissions imbalance‘, and produces frightening numbers. The great carbon divide describes the huge gap between the amount of carbon dioxide the rich versus the poor emit, and these numbers shocked even us.  What does this mean?  There have been many different studies, and all of them show terrifying results. One study from the Guardian and Oxfam, reports that the richest 1% of the world's population emit more carbon than the poorest 66%. The richest 1% consist of 77 million people, which may seem like a lot at first, but the poorest 66% refers to over 5 billion people! Africa, which is home to 17% of the world's population, only causes 4% of the world's emissions. This top 1% emitted 16% of global CO2 emissions in 2019, that's 5.9 billion tonnes of CO2. Modelling suggests that it would take someone who isn't in the top 1% about 150...
Post a Comment
Read more

Announcement: Amazon Rainforest Series

By
Post a Comment
Read more

How much do you know about trees? - Quiz

By
Hello, This month's quiz is all about trees. Questions: What is the name of the network that trees use to communicate? a) the mycorrhizal network b) the mythcorhinia network c) the symbocommunial network How much of the amazon rainforest has been lost due to deforestation in the last 50 years? a) 12% b) 17% c) 23% True or False? Over 75% of land-based species are found in forests? How much carbon do tropical forest contain? a) 230 gigatons b) 280 gigatons c) 330 gigatons In California, there is a rather strange tree that has survived 13 000 years by cloning itself. What species? a) Pin oak ;b) English oak c) Palmer's oak True or False? The oldest surviving tree species, Gingko trees, have been around since just after the meteor that killed off the dinosaurs struck. Where do acacia trees grow? a) cold and ha...
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

Ozone layer

By
Hi everyone, What even is ozone? And the ozone layer? Where does the hole in the ozone layer come from and what does it mean? Is it dangerous? What can be done? Often the ozone-talk can be complicated and confusing, keeping an overview is hard and understanding all the problems always difficult. Let us break it down a bit for you: What is the ozone layer? We'll start with the basics: The ozone layer is part of the stratosphere, which is the second layer of the Earth's atmosphere, between 10 and 50 km above the Earth's surface and made up of protective gases. One of these protective gases is ozone. There is not much ozone in the atmosphere, only 0.3 molecule of ozone per 1 million molecules of air. This is because ozone is chemically unstable and only forms when ultra violet radiation (UV light) hits oxygen and breaks the bonds between the atoms. It fact it is so unstable that even when it has formed, it breaks down again relatively quickly. This leads to ozone turning back ...
Post a Comment
Read more

Eco system Galápagos: Part 1 Geography

By
Hello and welcome to the first post about the Galapagos Islands. Currents and Winds The volcanic islands of Galápagos started to form 4 million years ago. Where they lie, is unique. They are situated directly on the equator, on the Nazca tectonic plate. The Galapagos Islands are on the crossroads of three currents. The cold South Equatorial Current flows westward towards Galapagos. The warm Panama Current runs in from the north. And finally, the deep sea Cromwell Current runs from the west. The Galapagos Islands are also where the Northeast Trade Wind meets the Southeast Trade Wind. Galapagos Hotspot 21 Volcanoes make up the Galápagos Islands with 13 still active. The reason for this volcanic activity is a giant hotspot under the island. A hotspot is a gigantic column of super heated molten lava, rising up towards the surface. It is immense; at least sixty miles (97 kilometers) across and 1800 miles (2897 kilometers) deep. It connects the islands to ...
Post a Comment
Read more

March Top Tips // 10 little things you can avoid in daily life

By Anonymous
Welcome to the Top Tips this month! We'll be talking about 10 things you can avoid using in everyday life. We know it's a really simple topic, but it can actually make quite a difference. The avoidable stuff will be things many use because they look nice or taste nice or similar, but aren't actually necessary. We will also write a couple of facts on these things, and give ideas on how you could substitute them if possible. Many might be very obvious, but think about it, do you actually not use them? Have fun! Chewing Gum Most people would not be surprised when told that lots of chewing gum have synthetic colouring and flavouring. However, most people would be surprised when told that chewing gum is largely made of plastic. What the companies call the "gum base" is plastic and partly made of the same stuff plastic bags are made of. The gum contains microplastics that, if you spit your gum on the ground often tend to get into the oce...
Post a Comment
Read more