It's 19th of November 2022 and the world population has reached 8 billion. It is probably the first time that the earth is inhabited by 8 billion population of single species. The earth is carrying an unprecedented load and in addition to that, the human activities has further increased the burden of the earth. We emit 51 billion tones of greenhouse gases in the earth's atmosphere each year and sadly this number is increasing. I guess we all know the negative effects of these gases be it in polluting atmosphere, depleting ozone layer, acid rain and many more, we all know these greenhouse gases like carbon dioxide, methane are bad. There are several green house gases contributing sectors but here I want to discuss one of the major greenhouse gas producer, the steel industry.
The Dark Reality of Steel Industry
It may come as a surprise to many of you but steel industry is responsible for a staggering 8% of the global greenhouse emission and ironically, we are actually going to need a lot more of steel to clean up our economies. So if you are someone who skips chemistry class or a non science guy, let's first learn about steel. Steel is just iron with tiny carbon atoms sprinkled. Iron makes 5% of the earth crust. The way to make steel is, first you do the mining to extract the iron ore then melt the iron and react with coal or charcoal. The iron ore is purified by heating it in blast furnace. In this process the oxygen atoms bind with the carbon atoms in coal leaving pure iron and a load of carbon dioxide. This process requires huge energy to power which comes from, you guessed it right, burning coal. In fact 72% of global steel production is based on burning coal in blast furnaces. These blast furnaces last about 15-20 years and requires restoration and for that extra energy and resources is required. This is why the steel industry is one of the major air polluter.
Solar Energy
Sun is the ultimate source of energy. At all times 173,000 terawatts solar energy reaches the earth which is 10,000 times the global energy requirement. It is estimated that 1.5 hours sunlight in earth can supply for the global energy consumption for a year. Many countries around the globe have realized this fact and have started to focus on the solar energy, which is as we all know is a renewable source that is sustainable unlike fossils. Countries are building these big solar parks realizing that in future we are really going to need it. Here we discuss about one such solar park that is present in India. Although, Morocco being the world's leader in solar energy with largest concentrate solar power plant, India has the largest photovoltaic solar park, the Bhadla solar park.
Bhadla Solar Park
This solar park is the world's largest solar park. It is located at village Bhadla in Jodhpur district of Rajasthan. This place is dry and has an average temperature of 46-48 degrees throughout the year which is ideal for solar park. This solar park occupies over 14,000 acres of land, an area of 56.6 square km. There are about 10 millions solar panels which are regularly cleaned and maintained by robots under human supervision. The capacity of this park is about 2245 megawatts, which can fulfill the entire energy requirement of Kolkata. Actually this project is a part of 1 lakh megawatts solar energy grand plan of Indian government.
PM Modi has pledged to increase the share of renewable energy in India by 2030 to a whopping 450 gigawatts. So this past decade, India has started to produce 5 times more renewable energy than previous decades. According to US based Institute for Energy Economics and Financial Analysis, out of 10 largest solar parks 5 are being constructed in India. This shows how much India is prioritizing the solar energy.
The research data by the Land Art Generator
According to US Department of Energy, the global energy consumption in all of it's forms is projected to reach 678 quadrillion Btw by 2030. Doing some math, as 1 Btw = 0.0002931 kwh, 678 quadrillion is equal to 198,721,800,000,000 kwh for an entire year. So LAG wondered how much land area will be required and what type of infrastructural investment will be required to supply that amount of power using only solar panels. Assuming the capacity of 0.2 kw per square km and an efficiency of 20%, the surface area required to meet that goal is 4,96,805 square km, which is roughly equal to the area of Spain. The idea is not constructing this entirely on a single land but several solar parks in different parts of the world. The picture below is the graphical representation of the above calculations where the red square indicates the places and the area required to build these solar parks. I will provide a link at the end of the blog where you can further study about this research.
I think up to this point, you are convinced that solar energy is the golden key to reduce carbon emission. It is renewable and sustainable. But it turns out that solar energy is not as green as you may think and here are the 3 main reasons ;
1) Manufacturing solar panels results in carbon emission
To manufacture solar panels, raw materials are required. For that mining is done then these are processed in the factories and majority of the processing is done by burning coal. This results in carbon emission. It is estimated that solar energy emits 43 gm of carbon dioxide per kwh consumed whereas this value for coal is 1001.
2) Toxic Chemicals
To produce panels, refined silicon is required and this produces silicon tetrachloride which is generally not recycled. If this chemical reaches water resources, it is hazardous to human health. Hydrogen Fluoride needed to clean solar wafers during production is highly corrosive. The thing is that we don't want to solve the climate change issue by inviting other environmental issues such as chemical issues.
3) Waste
The solar panels last around 25-30 years. As of now the waste heap of discarded panel is about 250 thousand metric tones and by 2050 it is expected to rise to about 78 million metric tones. The worrying thing is that the recycled silicon loses it's quality so it can't be used to make another solar panel and also the cost of recycling is high. These unrecycled things will create tons of wastes.
People talk about solar energy being green but it turns out that it is not completely green. It doesn't mean that we discard this energy but find an alternative to make it greener and that's where the Hydrogen comes into action.
Hydrogen
Again for those of you who skipped the Chemistry classes, Hydrogen is the first element in the periodic table. It is one of the most abundant element in the universe. It is also found at the core of the stars acting as fuel for nuclear fusion.
The great advantage of hydrogen is that it can be used as a replacement to the coal in the steel industry. The iron ore is reduced with hydrogen and as a result H20 is formed instead of C02. This will save an enormous amount of green house gas emission. The blast furnaces can be replaced by the electric furnaces. A Swedish steelmaker SSAB delivered the world's first fossil free steel in 2021. We can use hydrogen for all container ships operating from China to USA as a fuel, if the cargo load is reduced by a mere 5%. Short and mid range flights on hydrogen fuel could cut the aviation emission by up to a third. Realizing this, Airbus company is working to deploy 3 models in 2035 that uses hydrogen as a fuel. But there are some problems with it.
- First is that, 90% of today's hydrogen is made from natural gas and this hydrogen is called the gray hydrogen. It means it will have carbon emission.
- We need a lot of hydrogen, a lot because it has low energy density. Just to make the steels in the EU, we need about 6 million tones of hydrogen, which is a lot. This requires huge hydrogen manufacturing plants, huge investments and a lot of carbon emission.
- The third major problem is the problem of storage. If we produce that much amount of hydrogen, where are we going to keep them? It means we must again invest in the storage facility. We need to build these giant storage tanks over huge area of land and many manpower to care that. Hydrogen must be cared otherwise there will be the problem of leakage. All of this is pure headache.
- We can produce blue hydrogen from natural gas and trap the emitted C02 and store it in a process called the steam methane reforming. This will prevent the emission from reaching the atmosphere. But it turns out that blue hydrogen has greater green house footprint than hydrogen made by burning natural gas.
- There is a big leakage in distribution of hydrogen as a fuel.
- The geopolitical problem arises when a single country produces a lot of hydrogen and other nations have to depend on them. It will result in market monopoly.
But there are some positive signs too. To make hydrogen green, we must make sure that the hydrogen used to reduce iron is coming from electrolyzer that is operating on 100% green energy. And the price of these electrolyzers is also falling, which is a good news. We can use solar energy to do electrolysis at an unprecedented amount and produce green hydrogen. We can use the energy to charge the lithium ion battery in which there is only 20% loss. This is some sense can reduce the problem of leakage. To avoid the geopolitical problem, each country must invest to produce their own green hydrogen plants.
Here are some other alternative energy sources,
1) Hydroelectricity
A country like Nepal which is rich in water resources should focus on hydroelectricity rather than these hydrogen power plants. Nepal has an estimated capacity of around 83,000 megawatts of hydroelectricity. So they should center their attention to it rather than solar parks.
2) Geo thermal energy
Indonesia has a high potential for geothermal energy due to it's tectonically favored geography. The steam and hot water from the earth surface can be use to rotate turbines and produce electricity. The neat thing is that the water can again be recycled by sending it inside the earth surface. It is sustainable approach. But there is a limit to which the earth can be dug, above it earthquake can occur due to tectonic shifts.
3) Tidal energy
Tides are produced due to the gravitational attraction of moon on the earth. The neat thing about it is that it is predictable. We can know to some precision that where and when will the tide occur.
4) Nuclear energy
This form of energy is notoriously famous for the fact that it can blow up the earth but this form of energy could pioneer the future of energy.
5) Wind energy
This form is widely used today but is very costly.
Report by LAG :- https://landartgenerator.org/blagi/archives/127
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