5. Hydrogen as an energy carrier

How can hydrogen be useful in this quest of transitioning from fossil fuels to alternatives?

Introduction: When we talk about reducing fossil fuels, we talk about compatible alternatives that are just as capable of cutting emissions. One of the most recently talked about is one that forms a crucial component in completing the puzzle of alternatives – hydrogen. Hydrogen is the simplest and most abundant element on Earth. It is a gas that can be used for the decarbonization of a range of different major sectors that are hard to electrify. They include heavy industry (Industries manufacturing heavy items such as metals, machinery, vehicles, and construction materials), long-distance transportation, and energy production. Hydrogen exists as an energy carrier (A substance that contains energy that can later be converted to energy for use), chemically bonded with other atoms naturally like in water or hydrocarbons.

5.1: Hydrogen Production (methods of producing pure hydrogen)

Body: There are many different methods to separate and extract hydrogen for energy usage, which suffice to say, will vary the cost. An example would be electrolysis. Broadly speaking, electrolysis uses electricity to split molecules into separate cations and anions.

Body: Electrolysis of water would thus split water into hydrogen (H2) and oxygen (O2) gases. This process often takes place in an electrolysis cell comprising 2 electrodes, the anode, and the cathode, but in this case, would require a much bigger one. Electrolysis is a clean method as it does not produce any by-products. (Some methods are indirectly carbon-emitting like burning of fuel which is made of hydrocarbons. Though hydrogen is obtained, carbon is also released in the process.) The electricity used can also be from renewable energy or other clean energy sources, hence it is known as “clean hydrogen”.

Body: Another advantage that hydrogen has is its ability to be stored indefinitely, meaning it can be stored for future use. This is very useful as electricity from intermittent sources like solar, wind, or nuclear can be converted to hydrogen and stored for future use. This enables electricity generated from these sources to be kept and not lost after a few days and wasted, but instead, keep it to be used whenever we want.

Body: Unfortunately, many companies do not use electrolysis as much for the time being because of its requisite for a large amount of electricity. Because of this, companies prefer other methods such as steam methane reforming over electrolysis. It may take some time before electrolysis can be made cheaper and more effective so that it can become considerable for usage. On the bright side, there are already quite a handful of projects, such as the proton exchange membrane which is said to reach a level of 86% efficiency in extracting hydrogen. This might make paying for the electricity worth your while, especially when the electricity we use could come from the number of alternatives we already have, like solar power.

Body: Other methods of hydrogen production include steam methane reforming, gasification, partial oxidation, and hydrogen recovery. Moreover, the most common one, especially used for the purpose of generating hydrogen for energy use is steam methane reforming. Steam methane reforming basically converts natural gas which primarily consists of methane (CH4) into hydrogen (H2) and Carbon Dioxide (CO2) with the help of steam and heat. Natural gas will be first introduced into a chamber filled with high-temperature steam. From there, the mixture of the 2 vapors will be heated, causing a chemical reaction between methane and steam. The reaction essentially breaks down the methane molecules to form carbon dioxide and releases hydrogen as a byproduct. The hydrogen gas would then be separated from the mixture and either stored or utilized. The same goes for CO2 produced in the chemical reaction, they could either be captured or utilized for green reasons. Steam methane reforming is commonly used because it is a cost-effective solution to produce large quantities of hydrogen. This method is commonly known as gray hydrogen, and many other methods have their own color code to differentiate their amount of environmental impact and processes.

5.2: Hydrogen potential for decarbonization (hydrogen utilization)

Introduction: Hydrogen is mostly talked about because of its potential to decarbonize difficult industrial sectors, which are mentioned above (heavy industries, long-distance transportation, and energy production). Hydrogen-powered cars are also something commendable and starting to make their way into the market.

Body: : Firstly, let’s talk about hydrogen’s industrial usage in mainly these 3 aspects, steel, cement, and chemical production. There are definitely bigger sectors that gain more attention, but this is also no small piece of the climate change pie. Hydrogen can be the solution to these sectors that are especially hard to cut. One reason is that they are highly energy-intensive. For example, the production of steel requires a temperature of over 1600°C, and in order to get furnaces to become that hot, it would require an overwhelming amount of energy, which means a lot of fossil fuels have to be combusted, often coal. \

Body: This is where hydrogen comes in and can be used as an alternative fuel. However, there have yet to be many techniques right now which are completely green in the process of producing hydrogen. We would still need to rely on coal or natural gas to provide energy for the production of hydrogen. Therefore, the breakthrough in finally using completely green hydrogen in these industries would depend on finding more methods of producing hydrogen without indirectly contributing to carbon emissions.

Body: Moreover, hydrogen is used in the chemical industry in terms of serving as an alternative to fuels basically. For example, hydrogen can be combined with carbon dioxide by a process called hydrogenation and produce valuable chemicals and other materials like methanol and synthetic fuels. Another common instance is the production of ammonia, an essential molecule, particularly for fertilizers. Hydrogen can now take over fossil fuels for energy production during the Haber-Bosch process which combines nitrogen and oxygen to form ammonia. Almost all typical fertilizers used are made of ammonia. An example would be ammonium sulfate.

5.3: Hydrogen cars (hydrogen's potential to power our cars)

Body: Hydrogen can be used to power vehicles for long-distance transportation, and here’s why. For short-distance transportation, mainly BEVs (Battery Electric Vehicles) are adopted for adaptation in namely trucks and vans. BEVs are also known as pure electric vehicles and are vehicles driven entirely by a motor powered by a battery with electricity. BEVs are already starting to be used a lot in this industry since TCO (known as Total Cost of Ownership which basically means the actual cost quantified by the cost of the item across its entire life cycle) prices are being lowered due to rapidly declining battery costs and the production of new electric vehicles such as electric delivery vans.

Body: However, this vehicle type is not too suitable when we’re talking about long-distance yet quick kind of quality. Batteries are too heavy, charging speeds are slow, and electric stations have yet to be placed on certain routes, especially in challenging or suburban routes. Thus, we need a vehicle able to produce more energy on a single charge for longer distances and have quicker refueling. Hydrogen cars, known as FCVs (Fuel Cell Vehicles) can travel around 300-400 miles while electric cars travel around 100-200 before the gas tank becomes empty. They also take only a couple of minutes to charge while electric cars take up to 45 minutes to charge. Additionally, hydrogen cars’ lighter weights compared with batteries from electric cars allow a greater capacity to be stored. As a result, long-distance transportation, usually trucks, are focusing on hydrogen-powered fuels and hydrogen combustion.

Body: Hydrogen cars consist of an electric motor that combusts high-pressured hydrogen gas with oxygen to produce electricity and water vapor as the products after undergoing a reaction. Right now, the only major roadblock to transitioning into a hydrogen-powered car society would be its production, and possibly infrastructure accessibility (hydrogen stations). Even the great, Elon Musk, found hydrogen cars to be a bright idea with a lot of potential, as mentioned in one of his late interviews. After many years of skepticism, Elon Musk himself has announced that he would be switching his company's production of cars to hydrogen-powered ones as of 2024. His first launch of the hydrogen-powered car in 2024 would be called "ModelH".

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