Hydrogen, the fuel of the future. What's Up, Engineering Lovers, my name is Igor Felipe and today I'm here to talk about Hydrogen. Some of you may know that we have already made a video about the dangers of using homemade electrolysis with table salt to obtain hydrogen for vehicles.
And just to make it clear, CASEIRA means MADE AT HOME, using table salt to obtain hydrogen without chemical control, without electrical and physical control over electrolysis. This video received several comments saying that we had some connection with the oil industry and that we would be creating a conspiracy theory. But to show that we have nothing against using hydrogen as a fuel, this video is exclusive on the topic.
So, come on. Hydrogen is the most abundant element on Earth, however, it is almost always found as part of another compound such as water (H2O) or methane (CH4), and to be used in vehicles, it must be separated into pure hydrogen (H2) . Once separated into pure hydrogen, we combine it with oxygen in the air via a fuel cell, generating electricity and eliminating water through an electrochemical process.
Hydrogen can be produced from a variety of resources, including fossil fuels, biomass and also water electrolysis. The environmental impact and the energy efficiency of hydrogen depend on how it is produced, after all, if a process demands more energy than it is released, that process is not sustainable. And what are the ways to produce hydrogen?
Well, I separated two ways here. Firstly, we have the reform of natural gas or gasification of solid or liquid fuels: The synthesis gas, is a mixture of gas fuels and is produced by the gasification process. Basically it is created by the reaction of natural gas with steam at a high temperature and then the carbon monoxide will react with water, separating the additional hydrogen.
This method is the cheapest, most efficient and most common for the production of hydrogen. However, from an environmental point of view, this hydrogen production system is not considered sustainable, due to CO2 emissions, which contributes to the greenhouse effect. In addition, it depends on the extraction of natural gas, making this system dependent on fossil fuels.
Reforming natural gas using steam is responsible for most of the hydrogen produced in the United States annually. This synthesis gas can also be created by the reaction of coal or biomass, with steam at high temperature and oxygen in a pressurized gasifier. Second, we have Electrolysis.
In this process, an electric current divides water into hydrogen and oxygen. If electricity is produced from renewable sources, such as solar or wind, the resulting hydrogen will also be considered renewable and will have numerous benefits in terms of emissions. Hydrogen power generation projects are taking off, where surplus renewable electricity is used to produce hydrogen through electrolysis.
This process is quite simple. The electrolyzer consists of two metal electrodes and a continuous power supply that provides a negative and positive charge. In an ideal process of electrolysis of pure water, that is, distilled water, hydrogen will appear at the cathode, where electrons react with water to form hydrogen ions and hydroxides.
The negative ions now present in the water are attracted to the anode, where they are oxidized to form oxygen and water. The rate of oxygen and hydrogen production depends on the intensity of the electric current. But there is a problem, distilled water is not a good conductor of electricity.
And to achieve adequate hydrogen production, we need to increase the voltage on the electrodes, or increase the conductivity of the water. If we decide to increase the voltage at the source, we greatly decrease the efficiency of the process. After all, we will consume more energy in generation than the one released by hydrogen in the future, and this is not sustainable.
Therefore, it is much more efficient if we increase the conductivity of the medium. In this case, we add an electrolyte to increase this conductivity, usually some type of salt. However, we have to pay attention to the type of salt that we are going to use as an electrolyte.
If we use NaCl, which is nothing more than table salt, we will end up obtaining chlorine gas at the anode according to the formula shown on the screen. Just saying that I didn't make this up, it's just basic chemistry. This formula is present in many basic chemistry books in high school when we are going to study about electrolysis.
And it was precisely the recommendation not to use NaCl in electrolysis, the theme of the video that we posted in the past. We made the video just to warn about the risk of the chlorine gas released. And we were harshly criticized by some people, but a quick search on the internet and you find this same recommendation coming from several other people.
Think with me, most home hydrogen production systems are poorly installed in cars. A small leak in the system is enough for you to potentially release chlorine gas inside your vehicle. And believe me, even a small amount of chlorine gas already causes irritation to the eyes and mucous membranes, and this can cause an accident.
If you didn’t see our video talking about electrolysis with NaCL, I’ll leave a card at the end of this video, okay? But is there any salt that can be used that does not release something toxic? Yes, other materials less common than table salt can be used, such as Sodium Hydroxide, also known as Caustic Soda.
It even has the potential to release more hydrogen than table salt. You can also use baking soda. I will leave in the video description a material prepared by the BBC, showing the elements that will be obtained using various compounds with the electrolysis process.
But what is missing for hydrogen to become the fuel of the future? For hydrogen to become a popular fuel source, we first need to lower its production cost and be more competitive with batteries and fossil fuels. In this case, we have two possibilities.
We can improve the process by acting on the materials or using electricity from renewable energies to carry out electrolysis. The first option would be with the use of PEM, which stands for Polymer Electrolyte Membrane, or proton exchange membrane. This membrane is a solution that would make the process of obtaining hydrogen cheaper.
PEM replaces electrolyte-rich water with a solid polymer electrolyte membrane, positioned between the anode and the cathode, with channels to allow the flow of water, gas and solutions. The general chemical reaction is basically the same, however it requires less voltage to operate efficiently, and has a fast response time, making it ideal for integration into the grid as an energy storage method. Since it uses less voltage and can still be used as energy storage like a battery, this is where it really lowers costs.
The second option, on the other hand, is optimization from the point of view of electricity. The cost of producing hydrogen by electrolysis is totally dependent on electricity prices. The electrolysis process should take advantage of the use of cheaper and cleaner electrical energies.
After all, there is no point in generating electricity for clean purposes, since the generating source is polluting, such as thermoelectric plants. The greatest chance of success for hydrogen is to fuel a new economy by producing it from cheap renewable energy and allowing hydrogen to gradually grow to be the Earth's primary energy storage method. I separated here two videos that I am sure you will like and that controversial video about the danger of producing homemade hydrogen is one of them.
If you made it this far, don't forget to like and subscribe to the channel. That's it my friends, all the best and see you in the next video.
